Ofgem LTDS WG
This vocabulary is describing the LTDS Equipment profile.
Ofgem
vocabulary
LTDS Equipment Vocabulary
An electrical connection point (AC or DC) to a piece of conducting equipment. Terminals are connected at physical connection points called connectivity nodes.
ACDCTerminal
The operational limit sets at the terminal.
OperationalLimitSet
The orientation of the terminal connections for a multiple terminal conducting equipment. The sequence numbering starts with 1 and additional terminals should follow in increasing order. The first terminal is the "starting point" for a two terminal branch.
sequenceNumber
A wire or combination of wires, with consistent electrical characteristics, building a single electrical system, used to carry alternating current between points in the power system. For symmetrical, transposed three phase lines, it is sufficient to use attributes of the line segment, which describe impedances and admittances for the entire length of the segment. Additionally impedances can be computed by using length and associated per length impedances. The BaseVoltage at the two ends of ACLineSegments in a Line shall have the same BaseVoltage.nominalVoltage. However, boundary lines may have slightly different BaseVoltage.nominalVoltages and variation is allowed. Larger voltage difference in general requires use of an equivalent branch.
ACLineSegment
Positive sequence shunt (charging) susceptance, uniformly distributed, of the entire line section. This value represents the full charging over the full length of the line.
bch
Positive sequence shunt (charging) conductance, uniformly distributed, of the entire line section.
gch
Positive sequence series resistance of the entire line section.
Positive sequence series reactance of the entire line section.
Product of RMS value of the voltage and the RMS value of the in-phase component of the current.
ActivePower
multiplier
unit
value
Active power variation with current flow.
ActivePowerPerCurrentFlow
ActivePowerPerFrequency
AngleDegrees
Product of the RMS value of the voltage and the RMS value of the current.
ApparentPower
ApparentPowerLimit
The apparent power limuit series for this apparent power limit.
ApparentPowerLimitSeries
The normal apparent power limit. The attribute shall be a positive value or zero.
normalValue
An apparent power limit value which is valid for a time period.
ApparentPowerLimitDataPoint
The apparent power limit series that has this apparent power limit data point.
The number of the interval in a standalone schedule which describes the time period for which the apparent power limit is valid. It is only applicable if the series is being in conjunction with a standalone schedule.
intervalNumber
A set of apparent power limit data points, which can supply an ApparentPowerLimit with limit values which vary over time.
The apparent power limit that is part of this series.
The apparent power limit data point that is part of this series.
A rotating machine whose shaft rotates asynchronously with the electrical field. Also known as an induction machine with no external connection to the rotor windings, e.g. squirrel-cage induction machine.
AsynchronousMachine
Defines a system base voltage which is referenced.
BaseVoltage
All conducting equipment with this base voltage. Use only when there is no voltage level container used and only one base voltage applies. For example, not used for transformers.
ConductingEquipment
Transformer ends at the base voltage. This is essential for PU calculation.
TransformerEnds
The voltage levels having this base voltage.
VoltageLevel
The power system resource's base voltage. Shall be a positive value and not zero.
nominalVoltage
An electrochemical energy storage device.
BatteryUnit
Full energy storage capacity of the battery. The attribute shall be a positive value.
ratedE
The bio fuel consumed by the non-nuclear thermal generating unit.
BioFuel
The generating unit that has this bio fuel.
ThermalGeneratingUnit
bioFuelType
BioFuelKind
anaerobicGas
biomass
landfillGas
other
sewageGas
A type with the value space "true" and "false".
Boolean
Designates a connection point at which one or more model authority sets shall connect to. The location of the connection point as well as other properties are agreed between organisations responsible for the interconnection, hence all attributes of the class represent this agreement. It is primarily used in a boundary model authority set which can contain one or many BoundaryPoint-s among other Equipment-s and their connections.
BoundaryPoint
The connectivity node that is designated as a boundary point.
ConnectivityNode
A mechanical switching device capable of making, carrying, and breaking currents under normal circuit conditions and also making, carrying for a specified time, and breaking currents under specified abnormal circuit conditions e.g. those of short circuit.
Breaker
A conductor, or group of conductors, with negligible impedance, that serve to connect other conducting equipment within a single substation. Voltage measurements are typically obtained from voltage transformers that are connected to busbar sections. A bus bar section may have many physical terminals but for analysis is modelled with exactly one logical terminal.
BusbarSection
CAESPlant
A thermal generating unit may be a member of a compressed air energy storage plant.
The rated energy storage capacity. The attribute shall be a positive value.
energyStorageCapacity
Capacitive part of reactance (imaginary part of impedance), at rated frequency.
Capacitance
Factor by which voltage must be multiplied to give corresponding power lost from a circuit. Real part of admittance.
Conductance
The parts of the AC power system that are designed to carry current or that are conductively connected through terminals.
Base voltage of this conducting equipment. Use only when there is no voltage level container used and only one base voltage applies. For example, not used for transformers.
Conducting equipment have terminals that may be connected to other conducting equipment terminals via connectivity nodes or topological nodes.
Terminals
Combination of conducting material with consistent electrical characteristics, building a single electrical system, used to carry current between points in the power system.
Conductor
Segment length for calculating line section capabilities.
length
Connectivity nodes are points where terminals of AC conducting equipment are connected together with zero impedance.
The boundary point associated with the connectivity node.
ConnectivityNodeContainer
Terminals interconnected with zero impedance at a this connectivity node.
A base class for all objects that may contain connectivity nodes or topological nodes.
Connectivity nodes which belong to this connectivity node container.
ConnectivityNodes
A conductor, or group of conductors, with negligible impedance, that serve to connect other conducting equipment within a single substation and are modelled with a single logical terminal.
Connector
Monetary currencies. ISO 4217 standard including 3-character currency code.
Currency
AED
AFN
ALL
AMD
ANG
AOA
ARS
AUD
AWG
AZN
Bosnia and Herzegovina convertible mark.
BAM
BBD
BDT
BGN
BHD
BIF
Bermudian dollar (customarily known as Bermuda dollar).
BMD
BND
BOB
BOV
BRL
BSD
BTN
BWP
BYR
BZD
CAD
CDF
CHF
CLF
CLP
CNY
COP
COU
CRC
CUC
CUP
CVE
CZK
DJF
DKK
DOP
DZD
EEK
EGP
ERN
ETB
EUR
FJD
FKP
GBP
GEL
GHS
GIP
GMD
GNF
GTQ
GYD
HKD
HNL
HRK
HTG
HUF
IDR
ILS
INR
IQD
IRR
ISK
JMD
JOD
JPY
KES
KGS
KHR
KMF
KPW
KRW
KWD
KYD
KZT
LAK
LBP
LKR
LRD
LSL
LTL
LVL
LYD
MAD
MDL
MGA
MKD
MMK
MNT
MOP
MRO
MUR
MVR
MWK
MXN
MYR
MZN
NAD
NGN
NIO
NOK
NPR
NZD
OMR
PAB
PEN
PGK
PHP
PKR
PLN
PYG
QAR
RON
RSD
RUB
RWF
SAR
SBD
SCR
SDG
SEK
SGD
SHP
SLL
SOS
SRD
STD
SYP
SZL
THB
TJS
TMT
TND
TOP
TRY
TTD
TWD
TZS
UAH
UGX
USD
UYU
UZS
VEF
VND
VUV
WST
XAF
XCD
XOF
XPF
YER
ZAR
ZMK
ZWL
Electrical current with sign convention: positive flow is out of the conducting equipment into the connectivity node. Can be both AC and DC.
CurrentFlow
CurrentLimit
The current limuit series for this current limit.
CurrentLimitSeries
The normal value for limit on current flow. The attribute shall be a positive value or zero.
A current limit value which is valid for a time period.
CurrentLimitDataPoint
The current limit series that has this current limit data point.
The number of the interval in a standalone schedule which describes the time period for which the current limit is valid. It is only applicable if the series is being in conjunction with a standalone schedule.
A set of current limit data points, which can supply a CurrentLimit with limit values which vary over time.
The current limit data point that is part of this series.
A multi-purpose curve or functional relationship between an independent variable (X-axis) and dependent (Y-axis) variables.
Curve
The point data values that define this curve.
CurveDatas
curveStyle
xUnit
y1Unit
y2Unit
Multi-purpose data points for defining a curve. The use of this generic class is discouraged if a more specific class can be used to specify the X and Y axis values along with their specific data types.
CurveData
The data value of the X-axis variable, depending on the X-axis units.
xvalue
The data value of the first Y-axis variable, depending on the Y-axis units.
y1value
The data value of the second Y-axis variable (if present), depending on the Y-axis units.
y2value
CurveStyle
The Y-axis values are assumed constant until the next curve point and prior to the first curve point.
constantYValue
The Y-axis values are assumed to be a straight line between values. Also known as linear interpolation.
straightLineYValues
The way in which data point values are to be interpreted over the time period for which they are valid.
DataPointInterpretationKind
Data point value changes linearly though the its time period such that it reaches the value defined for the beginning of the next period.
linearInterpolation
Data point value exists at the time period’s start time, but no interpretation is provided for the remainder of time period. One use of this option could be for values intended for curve fitting.
none
Data point value persists throughout the time period for which it is valid.
stepwise
Date as "yyyy-mm-dd", which conforms with ISO 8601. UTC time zone is specified as "yyyy-mm-ddZ". A local timezone relative UTC is specified as "yyyy-mm-dd(+/-)hh:mm".
Date
Date and time as "yyyy-mm-ddThh:mm:ss.sss", which conforms with ISO 8601. UTC time zone is specified as "yyyy-mm-ddThh:mm:ss.sssZ". A local timezone relative UTC is specified as "yyyy-mm-ddThh:mm:ss.sss-hh:mm". The second component (shown here as "ss.sss") could have any number of digits in its fractional part to allow any kind of precision beyond seconds.
DateTime
Decimal is the base-10 notational system for representing real numbers.
Decimal
A circuit breaking device including disconnecting function, eliminating the need for separate disconnectors.
DisconnectingCircuitBreaker
A manually operated or motor operated mechanical switching device used for changing the connections in a circuit, or for isolating a circuit or equipment from a source of power. It is required to open or close circuits when negligible current is broken or made.
Disconnector
The method of grounding employed on a transformer winding.
EarthingMethodKind
notApplicable
reactance
Resistance grounding (LTDS), Neutral grounding resistors (GC0139).
resistance
solid
Through earth transformer (LTDS), Through earthing transformer (GC0139).
throughEarthTransformer
A connection of energy generation or consumption on the power system model.
EnergyConnection
Generic user of energy - a point of consumption on the power system model. EnergyConsumer.pfixed, .qfixed, .pfixedPct and .qfixedPct have meaning only if there is no LoadResponseCharacteristic associated with EnergyConsumer or if LoadResponseCharacteristic.exponentModel is set to False.
EnergyConsumer
The parts of a power system that are physical devices, electronic or mechanical.
Equipment
Additional equipment container beyond the primary equipment container. The equipment is contained in another equipment container, but also grouped with this equipment container.
AdditionalEquipmentContainer
EquipmentContainer
The aggregate flag provides an alternative way of representing an aggregated (equivalent) element. It is applicable in cases when the dedicated classes for equivalent equipment do not have all of the attributes necessary to represent the required level of detail. In case the flag is set to “true” the single instance of equipment represents multiple pieces of equipment that have been modelled together as an aggregate equivalent obtained by a network reduction procedure. Examples would be power transformers or synchronous machines operating in parallel modelled as a single aggregate power transformer or aggregate synchronous machine. The attribute is not used for EquivalentBranch, EquivalentShunt and EquivalentInjection.
aggregate
A modelling construct to provide a root class for containing equipment.
The additonal contained equipment. The equipment belong to the equipment container. The equipment is contained in another equipment container, but also grouped with this equipment container. Examples include when a switch contained in a substation is also desired to be grouped with a line contianer or when a switch is included in a secondary substation and also grouped in a feeder.
AdditionalGroupedEquipment
Equipments
The class represents equivalent branches. In cases where a transformer phase shift is modelled and the EquivalentBranch is spanning the same nodes, the impedance quantities for the EquivalentBranch shall consider the needed phase shift.
EquivalentBranch
Positive sequence series resistance of the reduced branch.
Resistance from terminal sequence 2 to terminal sequence 1 .Used for steady state power flow. This attribute is optional and represent unbalanced network such as off-nominal phase shifter. If only EquivalentBranch.r is given, then EquivalentBranch.r21 is assumed equal to EquivalentBranch.r. Usage rule : EquivalentBranch is a result of network reduction prior to the data exchange.
r21
Positive sequence series reactance of the reduced branch.
Reactance from terminal sequence 2 to terminal sequence 1. Used for steady state power flow. This attribute is optional and represents an unbalanced network such as off-nominal phase shifter. If only EquivalentBranch.x is given, then EquivalentBranch.x21 is assumed equal to EquivalentBranch.x. Usage rule: EquivalentBranch is a result of network reduction prior to the data exchange.
x21
The class represents equivalent objects that are the result of a network reduction. The class is the base for equivalent objects of different types.
EquivalentEquipment
This class represents equivalent injections (generation or load). Voltage regulation is allowed only at the point of connection.
EquivalentInjection
The reactive capability curve used by this equivalent injection.
ReactiveCapabilityCurve
maxP
Maximum reactive power of the injection. Used for modelling of infeed for load flow exchange. Not used for short circuit modelling. If maxQ and minQ are not used ReactiveCapabilityCurve can be used.
maxQ
minP
Minimum reactive power of the injection. Used for modelling of infeed for load flow exchange. Not used for short circuit modelling. If maxQ and minQ are not used ReactiveCapabilityCurve can be used.
minQ
Specifies whether or not the EquivalentInjection has the capability to regulate the local voltage. If true the EquivalentInjection can regulate. If false the EquivalentInjection cannot regulate. ReactiveCapabilityCurve can only be associated with EquivalentInjection if the flag is true.
regulationCapability
A floating point number. The range is unspecified and not limited.
Float
A flywheel is a mechanical device which uses the conservation of angular momentum to store rotational energy. Therefore, it is a heavy wheel attached to a rotating shaft so as to smooth out delivery of power from a motor to a machine. The inertia of the flywheel opposes and moderates fluctuations in the speed of the engine and stores the excess energy for intermittent use.
FlywheelUnit
The fossil fuel consumed by the non-nuclear thermal generating unit. For example, coal, oil, gas, etc. These are the specific fuels that the generating unit can consume.
FossilFuel
A thermal generating unit may have one or more fossil fuels.
The type of fossil fuel, such as coal, oil, or gas.
fossilFuelType
Frequency
FuelType
brownCoalLignite
Generic coal, not including lignite type.
coal
coalDerivedGas
gas
hardCoal
The fuel is lignite coal. Note that this is a special type of coal, so the other enum of coal is reserved for hard coal types or if the exact type of coal is not known.
lignite
oil
oilShale
Any fuel type not included in the rest of the enumerated value.
peat
An overcurrent protective device with a circuit opening fusible part that is heated and severed by the passage of overcurrent through it. A fuse is considered a switching device because it breaks current.
Fuse
A single or set of synchronous machines for converting mechanical power into alternating-current power. For example, individual machines within a set may be defined for scheduling purposes while a single control signal is derived for the set. In this case there would be a GeneratingUnit for each member of the set and an additional GeneratingUnit corresponding to the set.
GeneratingUnit
A synchronous machine may operate as a generator and as such becomes a member of a generating unit.
RotatingMachine
The net rated maximum capacity determined by subtracting the auxiliary power used to operate the internal plant machinery from the rated gross maximum capacity. The attribute shall be a positive value.
ratedNetMaxP
A geographical region of a power system network model.
GeographicalRegion
All sub-geographical regions within this geographical region.
Regions
Generating unit that is generating electrical power from geothermal energy. Technologies in use include dry steam power stations, flash steam power stations and binary cycle power stations.
GeothermalGeneratingUnit
A generating unit whose prime mover is a hydraulic turbine (e.g., Francis, Pelton, Kaplan).
HydroGeneratingUnit
The hydro generating unit belongs to a hydro power plant.
HydroPowerPlant
HydroPlantStorageKind
pumpedStorage
runOfRiver
storage
A hydro power station which can generate or pump. When generating, the generator turbines receive water from an upper reservoir. When pumping, the pumps receive their water from a lower reservoir.
HydroGeneratingUnits
The type of hydro power plant water storage.
hydroPlantStorageType
An IRI (Internationalized Resource Identifier) within an RDF graph is a Unicode string that conforms to the syntax defined in RFC 3987. The primitive is serialized as rdf:resource in RDFXML. IRIs in the RDF abstract syntax must be absolute, and may contain a fragment identifier. IRI equality: Two IRIs are equal if and only if they are equivalent under Simple String Comparison according to section 5.1 of [RFC3987]. Further normalization must not be performed when comparing IRIs for equality. IRIs are a generalization of URIs [RFC3986] that permits a wider range of Unicode characters. Every absolute URI and URL is an IRI, but not every IRI is an URI. When IRIs are used in operations that are only defined for URIs, they must first be converted according to the mapping defined in section 3.1 of [RFC3987]. A notable example is retrieval over the HTTP protocol. The mapping involves UTF-8 encoding of non-ASCII characters, %-encoding of octets not allowed in URIs, and Punycode-encoding of domain names.
IRI
This is a root class to provide common identification for all classes needing identification and naming attributes.
IdentifiedObject
The description is a free human readable text describing or naming the object. It may be non unique and may not correlate to a naming hierarchy.
description
Master resource identifier issued by a model authority. The mRID is unique within an exchange context. Global uniqueness is easily achieved by using a UUID, as specified in RFC 4122, for the mRID. The use of UUID is strongly recommended. For CIMXML data files in RDF syntax conforming to IEC 61970-552, the mRID is mapped to rdf:ID or rdf:about attributes that identify CIM object elements.
mRID
The name is any free human readable and possibly non unique text naming the object.
name
Inductive part of reactance (imaginary part of impedance), at rated frequency.
Inductance
An integer number. The range is unspecified and not limited.
Integer
Unit of length. It shall be a positive value or zero.
Length
LimitKind
alarmVoltage
Referring to the rating of the equipments, a voltage too high can lead to accelerated ageing or the destruction of the equipment. This limit type may or may not have duration.
highVoltage
A too low voltage can disturb the normal operation of some protections and transformer equipped with on-load tap changers, electronic power devices or can affect the behaviour of the auxiliaries of generation units. This limit type may or may not have duration.
lowVoltage
operationalVoltageLimit
The Permanent Admissible Transmission Loading (PATL) is the loading in amperes, MVA or MW that can be accepted by a network branch for an unlimited duration without any risk for the material. The OperationnalLimitType.isInfiniteDuration is set to true. There shall be only one OperationalLimitType of kind PATL per OperationalLimitSet if the PATL is ApparentPowerLimit, ActivePowerLimit, or CurrentLimit for a given Terminal or Equipment.
patl
Permanent Admissible Transmission Loading Threshold (PATLT) is a value in engineering units defined for PATL and calculated using a percentage less than 100 % of the PATL type intended to alert operators of an arising condition. The percentage should be given in the name of the OperationalLimitSet. The aceptableDuration is another way to express the severity of the limit.
patlt
stability
Temporarily Admissible Transmission Loading (TATL) which is the loading in amperes, MVA or MW that can be accepted by a branch for a certain limited duration. The TATL can be defined in different ways: as a fixed percentage of the PATL for a given time (for example, 115% of the PATL that can be accepted during 15 minutes), pairs of TATL type and Duration calculated for each line taking into account its particular configuration and conditions of functioning (for example, it can define a TATL acceptable during 20 minutes and another one acceptable during 10 minutes). Such a definition of TATL can depend on the initial operating conditions of the network element (sag situation of a line). The duration attribute can be used to define several TATL limit types. Hence multiple TATL limit values may exist having different durations.
tatl
Tripping Current (TC) is the ultimate intensity without any delay. It is defined as the threshold the line will trip without any possible remedial actions. The tripping of the network element is ordered by protections against short circuits or by overload protections, but in any case, the activation delay of these protections is not compatible with the reaction delay of an operator (less than one minute). The duration is always zero if the OperationalLimitType.acceptableDuration is exchanged. Only one limit value exists for the TC type.
Tripping Current Threshold (TCT) is a value in engineering units defined for TC and calculated using a percentage less than 100 % of the TC type intended to alert operators of an arising condition. The percentage should be given in the name of the OperationalLimitSet. The aceptableDuration is another way to express the severity of the limit.
tct
warningVoltage
Contains equipment beyond a substation belonging to a power transmission line.
Line
The sub-geographical region of the line.
Region
A linear shunt compensator has banks or sections with equal admittance values.
LinearShuntCompensator
Positive sequence shunt (charging) susceptance per section.
bPerSection
Positive sequence shunt (charging) conductance per section.
gPerSection
A mechanical switching device capable of making, carrying, and breaking currents under normal operating conditions.
LoadBreakSwitch
Money
MonthDay format as "--mm-dd", which conforms with XSD data type gMonthDay.
MonthDay
A non linear shunt compensator has bank or section admittance values that differ. The attributes g, b, g0 and b0 of the associated NonlinearShuntCompensatorPoint describe the total conductance and admittance of a NonlinearShuntCompensatorPoint at a section number specified by NonlinearShuntCompensatorPoint.sectionNumber.
NonlinearShuntCompensator
All points of the non-linear shunt compensator.
NonlinearShuntCompensatorPoints
A non linear shunt compensator bank or section admittance value. The number of NonlinearShuntCompenstorPoint instances associated with a NonlinearShuntCompensator shall be equal to ShuntCompensator.maximumSections. ShuntCompensator.sections shall only be set to one of the NonlinearShuntCompenstorPoint.sectionNumber. There is no interpolation between NonlinearShuntCompenstorPoint-s.
NonlinearShuntCompensatorPoint
Non-linear shunt compensator owning this point.
sectionNumber
NuclearGeneratingUnit
A value and normal value associated with a specific kind of limit. The sub class value and normalValue attributes vary inversely to the associated OperationalLimitType.acceptableDuration (acceptableDuration for short). If a particular piece of equipment has multiple operational limits of the same kind (apparent power, current, etc.), the limit with the greatest acceptableDuration shall have the smallest limit value and the limit with the smallest acceptableDuration shall have the largest limit value. Note: A large current can only be allowed to flow through a piece of equipment for a short duration without causing damage, but a lesser current can be allowed to flow for a longer duration.
OperationalLimit
The limit set to which the limit values belong.
The limit type associated with this limit.
OperationalLimitType
The direction attribute describes the side of a limit that is a violation.
OperationalLimitDirectionKind
An absoluteValue limit means that a monitored absolute value above the limit value is a violation.
absoluteValue
High means that a monitored value above the limit value is a violation. If applied to a terminal flow, the positive direction is into the terminal.
high
Low means a monitored value below the limit is a violation. If applied to a terminal flow, the positive direction is into the terminal.
low
A set of limits associated with equipment. Sets of limits might apply to a specific temperature, or season for example. A set of limits may contain different severities of limit levels that would apply to the same equipment. The set may contain limits of different types such as apparent power and current limits or high and low voltage limits that are logically applied together as a set.
OperationalLimitValue
The terminal where the operational limit set apply.
Terminal
The operational meaning of a category of limits.
The operational limits associated with this type of limit.
The nominal acceptable duration of the limit. Limits are commonly expressed in terms of the time limit for which the limit is normally acceptable. The actual acceptable duration of a specific limit may depend on other local factors such as temperature or wind speed. The attribute has meaning only if the flag isInfiniteDuration is set to false, hence it shall not be exchanged when isInfiniteDuration is set to true.
acceptableDuration
direction
Defines if the operational limit type has infinite duration. If true, the limit has infinite duration. If false, the limit has definite duration which is defined by the attribute acceptableDuration.
isInfiniteDuration
Types of limits defined in the ENTSO-E Operational Handbook Policy 3.
kind
Limit applies to transformer flow in reverse of normal (high to low voltage level) direction. High is the winding that has TransformerEnd.endNumber equal to 1. If true, the OperationalLimitType defines a type for reverse limit.
transformerReverseFlow
The other fuel consumed by the non-nuclear thermal generating unit.
OtherFuel
otherFuelType
OtherFuelKind
advanced
waste
Classifying instances of the same class, e.g. overhead and underground ACLineSegments. This classification mechanism is intended to provide flexibility outside the scope of this document, i.e. provide customisation that is non standard.
PSRType
Power system resources classified with this power system resource type.
PowerSystemResources
EQProfile
Percentage on a defined base. For example, specify as 100 to indicate at the defined base.
PerCent
A transformer phase shifting tap model that controls the phase angle difference across the power transformer and potentially the active power flow through the power transformer. This phase tap model may also impact the voltage magnitude.
PhaseTapChanger
Transformer end to which this phase tap changer belongs.
TransformerEnd
Describes the tap model for an asymmetrical phase shifting transformer in which the difference voltage vector adds to the in-phase winding. The out-of-phase winding is the transformer end where the tap changer is located. The angle between the in-phase and out-of-phase windings is named the winding connection angle. The phase shift depends on both the difference voltage magnitude and the winding connection angle.
PhaseTapChangerAsymmetrical
The phase angle between the in-phase winding and the out-of -phase winding used for creating phase shift. The out-of-phase winding produces what is known as the difference voltage. Setting this angle to 90 degrees is not the same as a symmetrical transformer. The attribute can only be multiples of 30 degrees. The allowed range is -150 degrees to 150 degrees excluding 0.
windingConnectionAngle
Describes a tap changer with a linear relation between the tap step and the phase angle difference across the transformer. This is a mathematical model that is an approximation of a real phase tap changer. The phase angle is computed as stepPhaseShiftIncrement times the tap position. The voltage magnitude of both sides is the same.
PhaseTapChangerLinear
Phase shift per step position. A positive value indicates a positive angle variation from the Terminal at the PowerTransformerEnd, where the TapChanger is located, into the transformer. The actual phase shift increment might be more accurately computed from the symmetrical or asymmetrical models or a tap step table lookup if those are available.
stepPhaseShiftIncrement
The reactance depends on the tap position according to a "u" shaped curve. The maximum reactance (xMax) appears at the low and high tap positions. Depending on the “u” curve the attribute can be either higher or lower than PowerTransformerEnd.x.
xMax
The non-linear phase tap changer describes the non-linear behaviour of a phase tap changer. This is a base class for the symmetrical and asymmetrical phase tap changer models. The details of these models can be found in IEC 61970-301.
PhaseTapChangerNonLinear
The voltage step increment on the out of phase winding (the PowerTransformerEnd where the TapChanger is located) specified in percent of rated voltage of the PowerTransformerEnd. A positive value means a positive voltage variation from the Terminal at the PowerTransformerEnd, where the TapChanger is located, into the transformer. When the increment is negative, the voltage decreases when the tap step increases.
voltageStepIncrement
Describes a symmetrical phase shifting transformer tap model in which the voltage magnitude of both sides is the same. The difference voltage magnitude is the base in an equal-sided triangle where the sides corresponds to the primary and secondary voltages. The phase angle difference corresponds to the top angle and can be expressed as twice the arctangent of half the total difference voltage.
PhaseTapChangerSymmetrical
Describes a tabular curve for how the phase angle difference and impedance varies with the tap step.
PhaseTapChangerTable
PhaseTapChangerTablePoint
The phase tap changers to which this phase tap table applies.
PhaseTapChangerTabular
Describes each tap step in the phase tap changer tabular curve.
The angle difference in degrees. A positive value indicates a positive angle variation from the Terminal at the PowerTransformerEnd, where the TapChanger is located, into the transformer.
angle
Describes a tap changer with a table defining the relation between the tap step and the phase angle difference across the transformer.
The phase tap changer table for this phase tap changer.
A photovoltaic device or an aggregation of such devices.
PhotoVoltaicUnit
An unit capable of either generating electrical energy from chemical reactions or using electrical energy to cause chemical reactions.
PowerElectricalChemicalUnit
A connection to the AC network for energy production or consumption that uses power electronics rather than rotating machines.
PowerElectronicsConnection
An AC network connection may have several power electronics units connecting through it.
PowerElectronicsUnit
The total active power export capacity permitted as per the connection agreement. The attribute shall have a positive value.
maxExportP
The total active power import capacity permitted as per the connection agreement. The attribute shall have a positive value.
maxImportP
A generating unit or battery or aggregation that connects to the AC network using power electronics rather than rotating machines.
A power electronics unit has a connection to the AC network.
Maximum active power limit. This is the maximum (nameplate) limit for the unit.
A wind generating unit that connects to the AC network with power electronics rather than rotating machines or an aggregation of such units.
PowerElectronicsWindUnit
A power system resource (PSR) can be an item of equipment such as a switch, an equipment container containing many individual items of equipment such as a substation, or an organisational entity such as sub-control area. Power system resources can have measurements associated.
PowerSystemResource
Custom classification for this power system resource.
An electrical device consisting of two or more coupled windings, with or without a magnetic core, for introducing mutual coupling between electric circuits. Transformers can be used to control voltage and phase shift (active power flow). A power transformer may be composed of separate transformer tanks that need not be identical. A power transformer can be modelled with or without tanks and is intended for use in both balanced and unbalanced representations. A power transformer typically has two terminals, but may have one (grounding), three or more terminals. The inherited association ConductingEquipment.BaseVoltage should not be used. The association from TransformerEnd to BaseVoltage should be used instead.
PowerTransformer
PowerTransformerEnd
Nature of transformer's reverse flow capability.
reverseFlowCapability
A PowerTransformerEnd is associated with each Terminal of a PowerTransformer. The impedance values r, r0, x, and x0 of a PowerTransformerEnd represents a star equivalent as follows. 1) for a two Terminal PowerTransformer the high voltage (TransformerEnd.endNumber=1) PowerTransformerEnd has non zero values on r, r0, x, and x0 while the low voltage (TransformerEnd.endNumber=2) PowerTransformerEnd has zero values for r, r0, x, and x0. Parameters are always provided, even if the PowerTransformerEnds have the same rated voltage. In this case, the parameters are provided at the PowerTransformerEnd which has TransformerEnd.endNumber equal to 1. 2) for a three Terminal PowerTransformer the three PowerTransformerEnds represent a star equivalent with each leg in the star represented by r, r0, x, and x0 values. 3) For a three Terminal transformer each PowerTransformerEnd shall have g, g0, b and b0 values corresponding to the no load losses distributed on the three PowerTransformerEnds. The total no load loss shunt impedances may also be placed at one of the PowerTransformerEnds, preferably the end numbered 1, having the shunt values on end 1. This is the preferred way. 4) for a PowerTransformer with more than three Terminals the PowerTransformerEnd impedance values cannot be used. Instead use the TransformerMeshImpedance or split the transformer into multiple PowerTransformers. Each PowerTransformerEnd must be contained by a PowerTransformer. Because a PowerTransformerEnd (or any other object) can not be contained by more than one parent, a PowerTransformerEnd can not have an association to an EquipmentContainer (Substation, VoltageLevel, etc).
The power transformer of this power transformer end.
Magnetizing branch susceptance (B mag). The value can be positive or negative.
connectionKind
Resistance (star-model) of the transformer end. The attribute shall be equal to or greater than zero for non-equivalent transformers.
Normal apparent power rating. The attribute shall be a positive value. For a two-winding transformer the values for the high and low voltage sides shall be identical.
ratedS
Rated voltage: phase-phase for three-phase windings, and either phase-phase or phase-neutral for single-phase windings. A high voltage side, as given by TransformerEnd.endNumber, shall have a ratedU that is greater than or equal to ratedU for the lower voltage sides. The attribute shall be a positive value.
ratedU
Positive sequence series reactance (star-model) of the transformer end.
A ProtectedSwitch is a switching device that can be operated by ProtectionEquipment.
ProtectedSwitch
A tap changer that changes the voltage ratio impacting the voltage magnitude but not the phase angle across the transformer. Angle sign convention (general): Positive value indicates a positive phase shift from the winding where the tap is located to the other winding (for a two-winding transformer).
RatioTapChanger
The tap ratio table for this ratio tap changer.
RatioTapChangerTable
Transformer end to which this ratio tap changer belongs.
Tap step increment, in per cent of rated voltage of the power transformer end, per step position. When the increment is negative, the voltage decreases when the tap step increases.
stepVoltageIncrement
Describes a curve for how the voltage magnitude and impedance varies with the tap step.
The ratio tap changer of this tap ratio table.
RatioTapChangerTablePoint
Describes each tap step in the ratio tap changer tabular curve.
Reactance (imaginary part of impedance), at rated frequency.
Reactance
Reactive power rating envelope versus the synchronous machine's active power, in both the generating and motoring modes. For each active power value there is a corresponding high and low reactive power limit value. Typically there will be a separate curve for each coolant condition, such as hydrogen pressure. The Y1 axis values represent reactive minimum and the Y2 axis values represent reactive maximum.
The equivalent injection using this reactive capability curve.
Product of RMS value of the voltage and the RMS value of the quadrature component of the current.
ReactivePower
RealEnergy
A type of conducting equipment that can regulate a quantity (i.e. voltage or flow) at a specific point in the network.
RegulatingCondEq
The regulating control scheme in which this equipment participates.
RegulatingControl
Specifies a set of equipment that works together to control a power system quantity such as voltage or flow. Remote bus voltage control is possible by specifying the controlled terminal located at some place remote from the controlling equipment. The specified terminal shall be associated with the connectivity node of the controlled point. The most specific subtype of RegulatingControl shall be used in case such equipment participate in the control, e.g. TapChangerControl for tap changers. For flow control, load sign convention is used, i.e. positive sign means flow out from a TopologicalNode (bus) into the conducting equipment. The attribute minAllowedTargetValue and maxAllowedTargetValue are required in the following cases: - For a power generating module operated in power factor control mode to specify maximum and minimum power factor values; - Whenever it is necessary to have an off center target voltage for the tap changer regulator. For instance, due to long cables to off shore wind farms and the need to have a simpler setup at the off shore transformer platform, the voltage is controlled from the land at the connection point for the off shore wind farm. Since there usually is a voltage rise along the cable, there is typical and overvoltage of up 3-4 kV compared to the on shore station. Thus in normal operation the tap changer on the on shore station is operated with a target set point, which is in the lower parts of the dead band. The attributes minAllowedTargetValue and maxAllowedTargetValue are not related to the attribute targetDeadband and thus they are not treated as an alternative of the targetDeadband. They are needed due to limitations in the local substation controller. The attribute targetDeadband is used to prevent the power flow from move the tap position in circles (hunting) that is to be used regardless of the attributes minAllowedTargetValue and maxAllowedTargetValue.
The equipment that participates in this regulating control scheme.
The terminal associated with this regulating control. The terminal is associated instead of a node, since the terminal could connect into either a topological node or a connectivity node. Sometimes it is useful to model regulation at a terminal of a bus bar object.
The regulating control mode presently available. This specification allows for determining the kind of regulation without need for obtaining the units from a schedule.
mode
The kind of regulation model. For example regulating voltage, reactive power, active power, etc.
RegulatingControlModeKind
activePower
admittance
currentFlow
powerFactor
reactivePower
Control switches on/off based on the local temperature (i.e., a thermostat).
temperature
Control switches on/off by time of day. The times may change on the weekend, or in different seasons.
timeScheduled
voltage
A set of intervals (regular or irregular) which defines a repeating pattern of time periods. The total duration of the pattern is inferred from the manner in which interval start times are specified, with start times expressed as a day of a month implying a schedule duration of a year.
RepeatingSchedule
the repeating schedule interval that defines the interval of the repeating schedule.
RepeatingScheduleInterval
A time period, with a specified start time, within a repeating schedule. Intervals within a repeating schedule are implicitly ordered by their start times. The interval with the earliest start time is implicitly numbered as interval 1 and the remaining implicitly ordered intervals are numbered incrementally (i.e., 2, 3, 4, etc.).
The repeating schedule that has this repeating schedule interval.
The beginning of the time period represented by the interval.
startAt
Resistance
Describes the transformer's reverse flow capability with respect to its normal flow capability.
ReverseFlowCapabilityKind
Transformer's reverse flow capability is different from its normal direction flow capability.
differentFromNormal
Transformer's reverse flow capability is unknown.
notYetDetermined
Transformer's reverse flow capability is same as its normal direction flow capability.
sameAsNormal
A rotating machine which may be used as a generator or motor.
RotationSpeed
Seconds
A set of data points which supply values which are valid over a set of time periods.
Series
The standalone schedule for this series.
StandaloneSchedule
Defines how values specified in data points are interpreted over their validity time period.
dataPointInterpretation
A Series Compensator is a series capacitor or reactor or an AC transmission line without charging susceptance. It is a two terminal device.
SeriesCompensator
A shunt capacitor or reactor or switchable bank of shunt capacitors or reactors. A section of a shunt compensator is an individual capacitor or reactor. A negative value for bPerSection indicates that the compensator is a reactor. ShuntCompensator is a single terminal device. Ground is implied.
ShuntCompensator
An automatic voltage regulation delay (AVRDelay) which is the time delay from a change in voltage to when the capacitor is allowed to change state. This filters out temporary changes in voltage.
aVRDelay
Used for Yn and Zn connections. True if the neutral is solidly grounded.
grounded
The maximum number of sections that may be switched in.
maximumSections
The voltage at which the nominal reactive power may be calculated. This should normally be within 10% of the voltage at which the capacitor is connected to the network.
nomU
The normal number of sections switched in. The value shall be between zero and ShuntCompensator.maximumSections.
normalSections
Voltage sensitivity required for the device to regulate the bus voltage, in voltage/reactive power.
voltageSensitivity
A solar thermal generating unit, connected to the grid by means of a rotating machine. This class does not represent photovoltaic (PV) generation.
SolarGeneratingUnit
A schedule made up of intervals, each of which can be referenced by data points in a series. An interval defines the time period for which the values of the data point are valid.
The series that has a standalone schedule.
A facility for providing variable and controllable shunt reactive power. The SVC typically consists of a stepdown transformer, filter, thyristor-controlled reactor, and thyristor-switched capacitor arms. The SVC may operate in fixed MVar output mode or in voltage control mode. When in voltage control mode, the output of the SVC will be proportional to the deviation of voltage at the controlled bus from the voltage setpoint. The SVC characteristic slope defines the proportion. If the voltage at the controlled bus is equal to the voltage setpoint, the SVC MVar output is zero.
StaticVarCompensator
Capacitive reactance at maximum capacitive reactive power. Shall always be positive.
capacitiveRating
Inductive reactance at maximum inductive reactive power. Shall always be negative.
inductiveRating
The characteristics slope of an SVC defines how the reactive power output changes in proportion to the difference between the regulated bus voltage and the voltage setpoint. The attribute shall be a positive value or zero.
slope
A string consisting of a sequence of characters. The character encoding is UTF-8. The string length is unspecified and unlimited.
String
A string consisting of a sequence of characters. The character encoding is UTF-8. The string length is unspecified and unlimited. The primitive is serialized as literal without language support.
StringFixedLanguage
An IRI (Internationalized Resource Identifier) within an RDF graph is a Unicode string that conforms to the syntax defined in RFC 3987. The primitive is serialized as literal without language support. IRIs in the RDF abstract syntax must be absolute, and may contain a fragment identifier. IRI equality: Two IRIs are equal if and only if they are equivalent under Simple String Comparison according to section 5.1 of [RFC3987]. Further normalization must not be performed when comparing IRIs for equality. IRIs are a generalization of URIs [RFC3986] that permits a wider range of Unicode characters. Every absolute URI and URL is an IRI, but not every IRI is an URI. When IRIs are used in operations that are only defined for URIs, they must first be converted according to the mapping defined in section 3.1 of [RFC3987]. A notable example is retrieval over the HTTP protocol. The mapping involves UTF-8 encoding of non-ASCII characters, %-encoding of octets not allowed in URIs, and Punycode-encoding of domain names.
StringIRI
A subset of a geographical region of a power system network model.
SubGeographicalRegion
The lines within the sub-geographical region.
Lines
The geographical region which this sub-geographical region is within.
The substations in this sub-geographical region.
Substations
A collection of equipment for purposes other than generation or utilization, through which electric energy in bulk is passed for the purposes of switching or modifying its characteristics.
Substation
The SubGeographicalRegion containing the substation.
The voltage levels within this substation.
VoltageLevels
Susceptance
A generic device designed to close, or open, or both, one or more electric circuits. All switches are two terminal devices including grounding switches. The ACDCTerminal.connected at the two sides of the switch shall not be considered for assessing switch connectivity, i.e. only Switch.open, .normalOpen and .locked are relevant.
Switch
The attribute is used in cases when no Measurement for the status value is present. If the Switch has a status measurement the Discrete.normalValue is expected to match with the Switch.normalOpen.
normalOpen
The maximum continuous current carrying capacity in amps governed by the device material and construction. The attribute shall be a positive value.
ratedCurrent
An electromechanical device that operates with shaft rotating synchronously with the network. It is a single machine operating either as a generator or synchronous condenser or pump.
SynchronousMachine
Modes that this synchronous machine can operate in.
type
SynchronousMachineKind
Indicates the synchronous machine can operate as a condenser.
condenser
Indicates the synchronous machine can operate as a generator.
generator
Indicates the synchronous machine can operate as a generator or as a condenser.
generatorOrCondenser
Indicates the synchronous machine can operate as a generator or as a condenser or as a motor.
generatorOrCondenserOrMotor
Indicates the synchronous machine can operate as a generator or as a motor.
generatorOrMotor
Indicates the synchronous machine can operate as a motor.
motor
Indicates the synchronous machine can operate as a motor or as a condenser.
motorOrCondenser
Mechanism for changing transformer winding tap positions.
TapChanger
The regulating control scheme in which this tap changer participates.
TapChangerControl
Highest possible tap step position, advance from neutral. The attribute shall be greater than lowStep.
highStep
Lowest possible tap step position, retard from neutral.
lowStep
Specifies whether or not a TapChanger has load tap changing capabilities.
ltcFlag
The neutral tap step position for this winding. The attribute shall be equal to or greater than lowStep and equal or less than highStep. It is the step position where the voltage is neutralU when the other terminals of the transformer are at the ratedU. If there are other tap changers on the transformer those taps are kept constant at their neutralStep.
neutralStep
Voltage at which the winding operates at the neutral tap setting. It is the voltage at the terminal of the PowerTransformerEnd associated with the tap changer when all tap changers on the transformer are at their neutralStep position. Normally neutralU of the tap changer is the same as ratedU of the PowerTransformerEnd, but it can differ in special cases such as when the tapping mechanism is separate from the winding more common on lower voltage transformers. This attribute is not relevant for PhaseTapChangerAsymmetrical, PhaseTapChangerSymmetrical and PhaseTapChangerLinear.
neutralU
The tap step position used in "normal" network operation for this winding. For a "Fixed" tap changer indicates the current physical tap setting. The attribute shall be equal to or greater than lowStep and equal to or less than highStep.
normalStep
Describes behaviour specific to tap changers, e.g. how the voltage at the end of a line varies with the load level and compensation of the voltage drop by tap adjustment.
The tap changers that participates in this regulating tap control scheme.
Describes each tap step in the tabular curve.
TapChangerTablePoint
The magnetizing branch susceptance deviation as a percentage of nominal value. The actual susceptance is calculated as follows: calculated magnetizing susceptance = b(nominal) * (1 + b(from this class)/100). The b(nominal) is defined as the static magnetizing susceptance on the associated power transformer end or ends. This model assumes the star impedance (pi model) form.
The magnetizing branch conductance deviation as a percentage of nominal value. The actual conductance is calculated as follows: calculated magnetizing conductance = g(nominal) * (1 + g(from this class)/100). The g(nominal) is defined as the static magnetizing conductance on the associated power transformer end or ends. This model assumes the star impedance (pi model) form.
The resistance deviation as a percentage of nominal value. The actual reactance is calculated as follows: calculated resistance = r(nominal) * (1 + r(from this class)/100). The r(nominal) is defined as the static resistance on the associated power transformer end or ends. This model assumes the star impedance (pi model) form.
The voltage at the tap step divided by rated voltage of the transformer end having the tap changer. Hence this is a value close to one. For example, if the ratio at step 1 is 1.01, and the rated voltage of the transformer end is 110kV, then the voltage obtained by setting the tap changer to step 1 to is 111.1kV.
ratio
step
The series reactance deviation as a percentage of nominal value. The actual reactance is calculated as follows: calculated reactance = x(nominal) * (1 + x(from this class)/100). The x(nominal) is defined as the static series reactance on the associated power transformer end or ends. This model assumes the star impedance (pi model) form.
An AC electrical connection point to a piece of conducting equipment. Terminals are connected at physical connection points called connectivity nodes.
The conducting equipment of the terminal. Conducting equipment have terminals that may be connected to other conducting equipment terminals via connectivity nodes or topological nodes.
The connectivity node to which this terminal connects with zero impedance.
All transformer ends connected at this terminal.
A generating unit whose prime mover could be a steam turbine, combustion turbine, or diesel engine.
The bio fuel used by this generating unit.
FossilFuels
The fuel that is used by this generating unit.
A conducting connection point of a power transformer. It corresponds to a physical transformer winding terminal. In earlier CIM versions, the TransformerWinding class served a similar purpose, but this class is more flexible because it associates to terminal but is not a specialization of ConductingEquipment.
Base voltage of the transformer end. This is essential for PU calculation.
Phase tap changer associated with this transformer end.
Ratio tap changer associated with this transformer end.
Terminal of the power transformer to which this transformer end belongs.
earthingMethod
Number for this transformer end, corresponding to the end's order in the power transformer vector group or phase angle clock number. Highest voltage winding should be 1. Each end within a power transformer should have a unique subsequent end number. Note the transformer end number need not match the terminal sequence number.
endNumber
A Uniform Resource Locator (URL), colloquially termed a web address, is a reference to a web resource that specifies its location on a computer network and a mechanism for retrieving it. A URL is a specific type of Uniform Resource Identifier (URI), although many people use the two terms interchangeably.URLs occur most commonly to reference web pages (http), but are also used for file transfer (ftp), email (mailto), database access (JDBC), and many other applications.
URL
The unit multipliers defined for the CIM. When applied to unit symbols, the unit symbol is treated as a derived unit. Regardless of the contents of the unit symbol text, the unit symbol shall be treated as if it were a single-character unit symbol. Unit symbols should not contain multipliers, and it should be left to the multiplier to define the multiple for an entire data type. For example, if a unit symbol is "m2Pers" and the multiplier is "k", then the value is k(m**2/s), and the multiplier applies to the entire final value, not to any individual part of the value. This can be conceptualized by substituting a derived unit symbol for the unit type. If one imagines that the symbol "Þ" represents the derived unit "m2Pers", then applying the multiplier "k" can be conceptualized simply as "kÞ". For example, the SI unit for mass is "kg" and not "g". If the unit symbol is defined as "kg", then the multiplier is applied to "kg" as a whole and does not replace the "k" in front of the "g". In this case, the multiplier of "m" would be used with the unit symbol of "kg" to represent one gram. As a text string, this violates the instructions in IEC 80000-1. However, because the unit symbol in CIM is treated as a derived unit instead of as an SI unit, it makes more sense to conceptualize the "kg" as if it were replaced by one of the proposed replacements for the SI mass symbol. If one imagines that the "kg" were replaced by a symbol "Þ", then it is easier to conceptualize the multiplier "m" as creating the proper unit "mÞ", and not the forbidden unit "mkg".
UnitMultiplier
micro
No multiplier or equivalently multiply by 1.
The derived units defined for usage in the CIM. In some cases, the derived unit is equal to an SI unit. Whenever possible, the standard derived symbol is used instead of the formula for the derived unit. For example, the unit symbol Farad is defined as "F" instead of "CPerV". In cases where a standard symbol does not exist for a derived unit, the formula for the unit is used as the unit symbol. For example, density does not have a standard symbol and so it is represented as "kgPerm3". With the exception of the "kg", which is an SI unit, the unit symbols do not contain multipliers and therefore represent the base derived unit to which a multiplier can be applied as a whole. Every unit symbol is treated as an unparseable text as if it were a single-letter symbol. The meaning of each unit symbol is defined by the accompanying descriptive text and not by the text contents of the unit symbol. To allow the widest possible range of serializations without requiring special character handling, several substitutions are made which deviate from the format described in IEC 80000-1. The division symbol "/" is replaced by the letters "Per". Exponents are written in plain text after the unit as "m3" instead of being formatted as "m" with a superscript of 3 or introducing a symbol as in "m^3". The degree symbol "°" is replaced with the letters "deg". Any clarification of the meaning for a substitution is included in the description for the unit symbol. Non-SI units are included in list of unit symbols to allow sources of data to be correctly labelled with their non-SI units (for example, a GPS sensor that is reporting numbers that represent feet instead of meters). This allows software to use the unit symbol information correctly convert and scale the raw data of those sources into SI-based units. The integer values are used for harmonization with IEC 61850.
UnitSymbol
Ampere-squared hour, ampere-squared hour.
A2h
Ampere squared time in square amperes (A²s).
A2s
Current, ratio of amperages. Note: Users may need to supply a prefix such as ‘m’ to show rates such as ‘mA/A’.
APerA
A/m, magnetic field strength, amperes per metre.
APerm
Btu
Exposure (x rays), coulombs per kilogram.
CPerkg
Surface charge density, coulombs per square metre.
CPerm2
Electric charge density, coulombs per cubic metre.
CPerm3
FPerm
Magnetic flux density, gausses (1 G = 10-4 T).
GyPers
HPerm
Frequency, rate of frequency change. Note: Users may need to supply a prefix such as ‘m’ to show rates such as ‘mHz/Hz’.
HzPerHz
Rate of change of frequency in hertz per second.
HzPers
JPerK
JPerkg
Specific heat capacity, specific entropy, joules per kilogram Kelvin.
JPerkgK
Insulation energy density, joules per square metre or watt second per square metre.
JPerm2
JPerm3
JPermol
Molar entropy, molar heat capacity, joules per mole kelvin.
JPermolK
JPers
Temperature change rate in kelvins per second.
KPers
Magnetic flux, maxwells (1 Mx = 10-8 Wb).
NPerm
Magnetic field in oersteds, (1 Oe = (103/4p) A/m).
Pressure in pascals (N/m²). Note: the absolute or relative measurement of pressure is implied with this entry. See below for more explicit forms.
Pressure change rate in pascals per second.
PaPers
Pas
SPerm
Magnetic flux density in teslas (Wb/m2).
V2h
Apparent power in volt amperes. See also real power and reactive power.
VAh
Reactive power in volt amperes reactive. The “reactive” or “imaginary” component of electrical power (VIsin(phi)). (See also real power and apparent power). Note: Different meter designs use different methods to arrive at their results. Some meters may compute reactive power as an arithmetic value, while others compute the value vectorially. The data consumer should determine the method in use and the suitability of the measurement for the intended purpose.
VAr
Reactive energy in volt ampere reactive hours.
VArh
VPerHz
Voltage, ratio of voltages. Note: Users may need to supply a prefix such as ‘m’ to show rates such as ‘mV/V’.
VPerV
Power factor, PF, the ratio of the active power to the apparent power. Note: The sign convention used for power factor will differ between IEC meters and EEI (ANSI) meters. It is assumed that the data consumers understand the type of meter being used and agree on the sign convention in use at any given utility.
VPerVA
VPerVAr
Electric field strength, volts per metre.
VPerm
Real power in watts (J/s). Electrical power may have real and reactive components. The real portion of electrical power (I²R or VIcos(phi)), is expressed in Watts. See also apparent power and reactive power.
Active power per current flow, watts per Ampere.
WPerA
Signal Strength, ratio of power. Note: Users may need to supply a prefix such as ‘m’ to show rates such as ‘mW/W’.
WPerW
Heat flux density, irradiance, watts per square metre.
WPerm2
Radiance, watts per square metre steradian.
WPerm2sr
Thermal conductivity in watt/metres kelvin.
WPermK
WPers
WPersr
anglemin
anglesec
bar
Data rate (baud) in characters per second.
charPers
character
Power factor, dimensionless. Note 1: This definition of power factor only holds for balanced systems. See the alternative definition under code 153. Note 2 : Beware of differing sign conventions in use between the IEC and EEI. It is assumed that the data consumer understands the type of meter in use and the sign convention in use by the utility.
cosPhi
count
Sound pressure level in decibels. Note: multiplier “d” is included in this unit symbol for compatibility with IEC 61850-7-3.
Power level (logarithmic ratio of signal strength , Bel-mW), normalized to 1mW. Note: multiplier “d” is included in this unit symbol for compatibility with IEC 61850-7-3.
dBm
deg
Relative temperature in degrees Celsius. In the SI unit system the symbol is °C. Electric charge is measured in coulomb that has the unit symbol C. To distinguish degree Celsius from coulomb the symbol used in the UML is degC. The reason for not using °C is that the special character ° is difficult to manage in software.
degC
ft3
Concentration, The ratio of the mass of a solute divided by the mass of the solution. Note: Users may need use a prefix such a ‘µ’ to express a quantity such as ‘µg/g’.
gPerg
Volume in gallons, US gallon (1 gal = 231 in3 = 128 fl ounce).
gal
kat
Catalytic activity concentration, katals per cubic metre.
katPerm3
Mass in kilograms. Note: multiplier “k” is included in this unit symbol for compatibility with IEC 61850-7-3.
Weight per energy in kilograms per joule (kg/J). Note: multiplier “k” is included in this unit symbol for compatibility with IEC 61850-7-3.
kgPerJ
Density in kilogram/cubic metres (kg/m³). Note: multiplier “k” is included in this unit symbol for compatibility with IEC 61850-7-3.
kgPerm3
Moment of mass in kilogram metres (kg·m) (first moment of mass). Note: multiplier “k” is included in this unit symbol for compatibility with IEC 61850-7-3.
kgm
Moment of mass in kilogram square metres (kg·m²) (Second moment of mass, commonly called the moment of inertia). Note: multiplier “k” is included in this unit symbol for compatibility with IEC 61850-7-3.
kgm2
Volume in litres, litre = dm3 = m3/1000.
lPerh
Concentration, The ratio of the volume of a solute divided by the volume of the solution. Note: Users may need use a prefix such a ‘µ’ to express a quantity such as ‘µL/L’.
lPerl
Volumetric flow rate in litres per second.
lPers
Viscosity in square metres / second (m²/s).
m2Pers
Volume, cubic metres, with the value compensated for weather effects.
m3Compensated
Volumetric flow rate, cubic metres per hour.
m3Perh
Specific volume, cubic metres per kilogram, v.
m3Perkg
Volumetric flow rate in cubic metres per second (m³/s).
m3Pers
Volume, cubic metres, with the value uncompensated for weather effects.
m3Uncompensated
Fuel efficiency in metres per cubic metres (m/m³).
mPerm3
mPers
Acceleration in metres per second squared (m/s²).
mPers2
min
Pressure, millimetres of mercury (1 mmHg is approximately 133.3 Pa).
mmHg
mol
Concentration, Molality, the amount of solute in moles and the amount of solvent in kilograms.
molPerkg
Concentration, The amount of substance concentration, (c), the amount of solvent in moles divided by the volume of solution in m³.
molPerm3
Concentration, Molar fraction, the ratio of the molar amount of a solute divided by the molar amount of the solution.
molPermol
Dimension less quantity, e.g. count, per unit, etc.
ohm
Electric resistance per length in ohms per metre ((V/A)/m).
ohmPerm
ohmm
onePerHz
onePerm
ppm
rad
Angular velocity in radians per second (rad/s).
radPers
Angular acceleration, radians per second squared.
radPers2
rev
Rotations per second (1/s). See also Hz (1/s).
rotPers
Time, Ratio of time. Note: Users may need to supply a prefix such as ‘µ’ to show rates such as ‘µs/s’.
sPers
therm
Mass in tons, “tonne” or “metric ton” (1000 kg = 1 Mg).
tonne
Electrical voltage, can be both AC and DC.
Voltage
A collection of equipment at one common system voltage forming a switchgear. The equipment typically consists of breakers, busbars, instrumentation, control, regulation and protection devices as well as assemblies of all these.
The base voltage used for all equipment within the voltage level.
VoltagePerReactivePower
A wind driven generating unit, connected to the grid by means of a rotating machine. May be used to represent a single turbine or an aggregation.
WindGeneratingUnit
WindingConnection
Independent winding, for single-phase connections.
Wye, with neutral brought out for grounding.
ZigZag, with neutral brought out for grounding.