IEC TR 61850-7-510:2012

IEC/TR 61850-7-510 ®
Edition 1.0 2012-03
TECHNICAL
REPORT
colour
inside
Communication networks and systems for power utility automation –
Part 7-510: Basic communication structure – Hydroelectric power plants –
Modelling concepts and guidelines

IEC/TR 61850-7-510:2012(E)
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IEC/TR 61850-7-510 ®
Edition 1.0 2012-03
TECHNICAL
REPORT
colour
inside
Communication networks and systems for power utility automation –

Part 7-510: Basic communication structure – Hydroelectric power plants –

Modelling concepts and guidelines

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XC
ICS 33.200 ISBN 978-2-8322-0046-9

– 2 – TR 61850-7-510 © IEC:2012(E)

CONTENTS
FOREWORD . 6
INTRODUCTION . 8
1 Scope . 9
2 Normative references . 9
3 Overall communication structure in a hydropower plant . 10
3.1 Abstract communication structure . 10
3.2 Communication network . 10
3.3 Operational modes . 12
3.4 Fundamental control strategies . 13
3.5 Hydro power plant specific information . 14
4 Structuring control systems . 16
4.1 Basic use of logical nodes . 16
4.2 Logical device modelling . 16
4.3 Example of application for an excitation system . 19
4.3.1 General . 19
4.3.2 Voltage regulation example . 22
4.3.3 PSS example . 24
4.4 Example of application for a turbine governor system . 25
4.4.1 Conditions of this example . 25
4.4.2 Signal hierarchy . 25
4.4.3 Basic overview . 26
4.4.4 Detailed description of used structure . 28
4.5 Examples of how to reference a start / stop sequencer of a unit . 34
4.5.1 General . 34
4.5.2 Unit sequences definition with IEC 61850 . 34
4.5.3 Start sequence from a state “stopped” to a state "speed no load not
excited” (included in LD named “SEQ_SnlNexStr”) . 35
4.5.4 Start sequence from state “speed no load not excited” to state
“generation” (included in LD named “SEQ_SnlExcStr” and
“SEQ_GenStr”) . 37
4.5.5 Stop sequence from state “generator” to state “speed no load not
excited” (included in LD named “SEQ_GridFaultStop”) . 38
4.5.6 Shutdown sequence from state “generator” to state “stopped”
(SEQ_NormalStop) . 40
4.5.7 Quick shutdown sequence from state “generator” to state “stopped”
(SEQ_QuickStop) . 42
4.5.8 Emergency shutdown sequence from state “generator” to state
“stopped” (SEQ_EmgStop) . 45
5 Variable speed system example . 47
5.1 Example of block diagrams and logical nodes of variable speed pumped
storage system . 47
5.2 Example of application for an excitation system of variable speed pumped
storage . 49
5.2.1 General . 49
5.2.2 Automatic power regulator example . 49

TR 61850-7-510 © IEC:2012(E) – 3 –
5.2.3 Power detector example . 50
5.2.4 Gate pulse generator example . 50
5.3 Example of governor system . 51
5.3.1 Guide vane opening function example . 51
5.3.2 Guide vane controller example . 52
5.3.3 Speed controller example . 53
5.3.4 Optimum speed function example . 53
5.4 Example of how to reference a start / stop sequencer for variable speed
pumped storage system . 54
5.4.1 Unit sequences definition for conventional and variable speed
pumped storage . 54
5.4.2 Start sequence from a state "Stopped" to a state "Synchronous
Condenser (SC) mode in pump direction" . 55
5.4.3 Start sequence from a state "Synchronous Condenser (SC) mode in
Pump direction" to a state "Pumping". 56
5.4.4 Mode Transition sequence from a state "Pumping" to a state
"Synchronous Condenser (SC) mode in Pump direction" . 57
5.4.5 Sequence from a state "pumping" to a state "stopped" . 58
5.4.6 Emergency shutdown sequence from a state "pumping" to a state
"stopped" . 60
5.4.7 Shutdown sequence from a state "Synchronous Condenser (SC)
mode in pump direction" to a state "stopped" . 61
5.4.8 Emergency shutdown sequence from a state "Synchronous
Condenser (SC) mode in pump direction" to a state "stopped" . 62
6 Pump start priorities of a high pressure oil system . 64
6.1 Example of a pump start priority for high pressure oil system . 64
6.1.1 General . 64
6.1.2 Sequence to manage a pump start priorities . 64
6.1.3 Sequence to manage a pump . 67
7 Addressing structures, examples of mapping . 68
7.1 Basic principles (IEC 61850-6) . 68
7.2 Decentralised ICD file management. 68
7.3 Centralised ICD file management . 69
7.4 Power plant structure – ISO/TS 16952-10 (Reference Designation System –
Power Plants) . 70
7.4.1 ISO/TS 16952-10 (Reference Designation System – Power Plants) . 70
7.4.2 Example 1: Wicket gate indications . 73
7.4.3 Example 2: 3 Phase Measurement. 74
7.4.4 Example 3: Speed Controller . 74
7.4.5 Example 4: Speed measurement with some thresholds . 75
7.4.6 Example 5: Common turbine information . 76
8 Examples of how to use various types of curves and curve shape descriptions . 76
9 Examples of voltage matching function . 80
Bibliography . 82

Figure 1 – Structure of a hydropower plant . 10
Figure 2 – Simplified network of a hydropower plant . 12
Figure 3 – Principles for the joint control function . 14
Figure 4 – Water flow control of a turbine. 15

– 4 – TR 61850-7-510 © IEC:2012(E)
Figure 5 – Pressurised oil systems with LD suffix and with LN prefix . 18
Figure 6 – Examples of logical nodes used in an excitation system . 19
Figure 7 – Example of logical devices of the regulation part of an excitation system . 21
Figure 8 – AVR basic regulator . 22
Figure 9 – Superimposed regulators, power factor regulator . 22
Figure 10 – Superimposed regulators, over-excitation limiter . 23
Figure 11 – Superimposed regulators, under-excitation limiter . 23
Figure 12 – Superimposed regulators, follow up . 24
Figure 13 – Power system stabilizer function . 24
Figure 14 – Signal hierarchy . 25
Figure 15 – Use of Logical Node HGOV . 27
Figure 16 – Governor control . 29
Figure 17 – Flow control . 30
Figure 18 – Level control . 31
Figure 19 – Speed control . 32
Figure 20 – Limitations . 33
Figure 21 – Actuator control . 33
Figure 22 – Sequencer overview . 34
Figure 23 – Typical block diagram in pumping operation . 47
Figure 24 – Typical block diagram in generating operation . 48
Figure 25 – Typical block diagram in synchronous condenser mode . 48
Figure 26 – Automatic power regulator. 49
Figure 27 – Power detector . 50
Figure 28 – Gate pulse generator . 50
Figure 29 – Guide vane opening function . 51
Figure 30 – Guide vane controller . 52
Figure 31 – Speed controller . 53
Figure 32 – Optimum speed function . 53
Figure 33 – Sequencer overview . 54
Figure 34 – Graphical representation of the high pressure oil pumping unit. 64
Figure 35 – Example of pump priority start logic sequence . 66
Figure 36 – Example of pump start logic sequence . 68
Figure 37 – Exchange of ICD files between system configurators . 69
Figure 38 – Static Data exchange with vendor's configuration tool . 70
Figure 39 – Tree structure of a system using RDS-PP . 72
Figure 40 – Hydraulic correlation curve . 77
Figure 41 – Turbine correlation curve . 80
Figure 42 – Example of traditional voltage adjusting pulses . 80
Figure 43 – Example of mapping of the pulse time in IEC 61850 . 80
Figure 44 – Example of an IEC 61850 voltage adjusting command . 81

Table 1 – IED within a simplified single unit power plant . 11
Table 2 – Recommended LN prefixes . 16

TR 61850-7-510 © IEC:2012(E) – 5 –
Table 3 – Logical device structure. 20
Table 4 – Logical device names for functions . 26
Table 5 – Typical sequences. 35
Table 6 – Logical device names for sequence function groups . 54
Table 7 – RDS-PP designation codes for Hydropower use . 71

– 6 – TR 61850-7-510 © IEC:2012(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
COMMUNICATION NETWORKS AND SYSTEMS
FOR POWER UTILITY AUTOMATION –

Part 7-510: Basic communication structure –
Hydroelectric power plants –
Modelling concepts and guidelines

FOREWORD
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
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The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose the publication of a technical report when it has collected
data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
IEC 61850-7-510, which is a technical report, has been prepared by IEC technical committee
57: Power systems management and associated information exchange.

TR 61850-7-510 © IEC:2012(E) – 7 –
The text of this technical report is based on the following documents:
Enquiry draft Report on voting
57/1143/DTR 57/1203/RVC
Full information on the voting for the approval of this technical report can be found in the
report on voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of the IEC 61850 series, under the general title: Communication networks
and systems for power utility automation, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
A bilingual version of this technical report may be issued at a later date.

– 8 – TR 61850-7-510 © IEC:2012(E)
INTRODUCTION
This Technical Report is connected with IEC 61850-7-410, as well as IEC 61850-7-4:2010,
explaining how the control system and other functions in a hydropower plant can use logical
nodes and information exchange services within the complete IEC 61850 package to specify
the information needed and generated by, and exchanged between functions.
The dynamic exchange of values by using polling, GOOSE, Reporting or Sampled Values is
beyond the scope of this report. This data flow is specified in the engineering work flow
defined in IEC 61850-5; this part of IEC 61850 applies also to applications in hydro power
plants.
TR 61850-7-510 © IEC:2012(E) – 9 –
COMMUNICATION NETWORKS AND SYSTEMS
FOR POWER UTILITY AUTOMATION –

Part 7-510: Basic communication structure –
Hydroelectric power plants –
Modelling concepts and guidelines

1 Scope
This part of IEC 61850 is intended to provide explanations on how to use the Logical Nodes
defined in IEC 61850-7-410 as well as other documents in the IEC 61850 series to model
complex control functions in power plants, including variable speed pumped storage power
plants.
IEC 61850-7-410 introduced the general modelling concepts of IEC 61850 to hydroelectric
power plants. It is however not obvious from the standard how the modelling concepts can be
implemented in actual power plants.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60870-5-104, Telecontrol equipment and systems – Part 5-104: Transmission protocols –
Network access for IEC 60870-5-101 using standard transport profiles
IEC 61850-5:2003, Communication networks and systems in substations – Part 5:
Communication requirements for functions and device models
IEC 61850-6, Communication networks and systems for power utility automation – Part 6:
Configuration description language for communication in electrical substations related to IEDs
IEC 61850-7-2, Communication networks and systems for power utility automation – Part 7-2:
Basic information and communication structure – Abstract communication service interface
(ACSI)
IEC 61850-7-3, Communication networks and systems for power utility automation – Part 7-3:
Basic communication structure – Common data classes
IEC 61850-7-4:2010, Communication networks and systems for power utility automation –
Part 7-4: Basic communication structure – Compatible logical node classes and data object
classes
IEC 61850-7-410, Communication networks and systems for power utility automation –
Part 7-410: Hydroelectric power plants – Communication for monitoring and control
IEC 61850-8-1, Communication networks and systems for power utility automation – Part 8-1:
Specific communication service mapping (SCSM) – Mappings to MMS (ISO 9506-1 and
ISO 9506-2) and to ISO/IEC 8802-3

– 10 – TR 61850-7-510 © IEC:2012(E)
IEC 61850-9-2, Communication networks and systems for power utility automation – Part 9-2:
Specific communication service mapping (SCSM) – Sampled values over ISO/IEC 8802-3
ISO/TS 16952-10, Technical product documentation – Reference designation system –
Part 10: Power plants
3 Overall communication structure in a hydropower plant
3.1 Abstract communication structure
Figure 1 is based on the substation structure described in IEC 61850-6. A typical power plant
will include a “substation” part that will be identical to what is described in the IEC 61850
series. The generating units with their related equipment are added to the basic structure.
A generating unit consists of a turbine-generator set with auxiliary equipment and supporting
functions. Generator transformers can be referenced as normal substation transformers; there
is not always any one-to-one connection between generating units and transformers.
The dam is a different case. There is always at least one dam associated with a hydropower
plant. There are however reservoirs that are not related to any specific power plant, equally
there are power plants from which more than one dam is being controlled. There can also be
dams with more than one hydropower plant. While all other objects can be addressed through
a specific power plant, dams might have to be addressed directly.
River system
Unit (generating unit) Logical system
Dam/reservoir
Hydro station Function (common) Sub-function Equipment
Transformer
Voltage level Bay
IEC  333/12
Figure 1 – Structure of a hydropower plant
There is however no standardised way of arranging overall control functions, the structure will
depend on whether the plant is manned or remote operated, as well as traditions within the
utility that owns the plant. In order to cover most arrangements, some of the Logical Nodes
defined in this document are more or less overlapping. This will allow the user to arrange
Logical Devices by selecting the most appropriate Logical Nodes that suits the actual design
and methods of operation of the plant. Other Logical Nodes are very small, in order to provide
simple building blocks that will allow as much freedom as possible in arranging the control
system.
3.2 Communication network
Defining a station communication network is one of the primary steps for defining how the
logical devices will be distributed among IEDs. The decision of where to nest the logical
device is relative to the physical connection of an IED and the field instrumentation. Table 1
lists an example of physical devices used for control of a small hydropower plant.

TR 61850-7-510 © IEC:2012(E) – 11 –
Table 1 – IED within a simplified single unit power plant
Intelligent Description Example of types of logical Devices
electronic device nested in an IED
IED1 Intake valve controller Valve {A, B}
IED2 Turbine controller and speed governor Actuators, Controllers, Turbine information
IED3 High pressure oil system controller Tank, Pump A, Pump B
IED4 Generator monitoring system Phase Windings{A,B,C}, Eccentricity
IED5 Excitation system Logical device group reference: Regulation,
Controls, Field Breaker, Protection
IED6 Bearing monitoring system Thrust bearing, guide bearing, and
generator bearing
IED7 Dam monitoring system Spillway gate{1,2} and dam
Unit IED Unit acquisition and control Logical device group reference: sequences
and Alarm grouping
Common IED Remote terminal unit Nil
Merging unit 1 Current- and voltage measurements at Merging Unit
generator
Merging unit 2 Current- and voltage measurements in MV Merging Unit
Merging unit 3 Current- and voltage measurements in HV Merging Unit
PROT1 T Primary transformer protection Protection, measurement
PROT2 T Secondary transformer protection Protection, measurement
PROT1 G Primary generator protection Protection, measurement
PROT2 G Secondary generator protection Protection, measurement

The following example in Figure 2 shows a simplified network of a single unit power plant. The
IEDs exchange information and control commands using MMS (IEC 61850-8-1), send trip
commands via GOOSE messaging (IEC 61850-9-2) and get information instantaneous current
and voltage reading via sample value (IEC 61850-9-2). The logical devices are distributed
among IEDs along functional groupings. The information is pushed to the dispatch centre via
a data concentrator which is the remote terminal unit using IEC 60870-5-104.

– 12 – TR 61850-7-510 © IEC:2012(E)

IEC  334/12
Figure 2 – Simplified network of a hydropower plant
3.3 Operational modes
A power plant can be operated in different modes: active power production mode or
condenser mode. The generator can be used as a pure synchronous condenser, without any
active power production and with the runner spinning in air.
In a pumped storage plant, there is a motor mode for the generator. A generator in a pumped
storage plant can also be used for voltage control in a synchronous condenser mode, in this
case normally with an empty turbine chamber.
The following steady states are defined for the unit:
Stopped – Unit is at standstill
Speed no load, not excited – No field current is applied, no voltage is generated; the
generator is running at rated speed but not connected to any external load.
Speed no load, excited – Field current is applied and a voltage is generated, the generator is
however not connected to any external load, there is no significant stator current.
Synchronised – The generator is synchronised to an external network. This is the normal
status of an operating generator.
Synchronised in condenser mode – The generator is synchronised. However it does not
primarily produce active power. In condenser mode, it will produce or consume reactive
power.
Island operation mode – The external network has been separated and the power plant shall
control the frequency.
TR 61850-7-510 © IEC:2012(E) – 13 –
Local supply mode – In case of a larger disturbance of the external network, one or more
generators in a power plant can be set at a minimum production to provide power for local
supply only. This type of operation is common in thermal power plants to shorten the start-up
time once the network is restored, but can also be used in hydropower plants for practical
reasons.
3.4 Fundamental control strategies
The control of hydropower plants can follow different strategies, depending on the external
requirements put on the operation of the system.
Speed control in isolated mode:
The purpose of the speed control basically is to maintain constant frequency. For more
detailed description, see IEC 61362.
Active power control:
The active power output control with a separate power controller is applied with the unit
connected to the grid. For more detailed description, see IEC 61362.
Reactive power control:
Reactive power control includes voltage and power factor control. This can include
synchronous condenser mode without active power output, but also added to active power
production.
Water flow control:
In this type of control, the power production is roughly adapted to the water flow that is
available at the moment. The rate of flow is controlled while the water level is allowed to vary
between high and low alarm levels in the dams. The dams are classified after the time over
which the inflow and outflow shall add up (daily, weekly, etc.).
Water level control:
In some locations, there are strict limits imposed on the allowed variation of the water level of
the dam. This might be due to maritime shipping or by other environmental requirements. In
this case, the upper water level of the dam is the overriding concern; power production is
adjusted by the water level control function to provide correct flow to maintain the water level.
Cascade control:
In rivers with more than one power plant, the overall water flow in the river is coordinated
between plants to ensure an optimal use of the water. Each individual plant can be operated
according to the water level model or the water flow model as best suited, depending on the
capacity of the local dam and allowed variation in water levels. The coordination is normally
done at dispatch centre level, but power plants often have feed-forward functions that
automatically will notify the next plant downstream if there is a sudden change of water flow.
Power plants with more than one generating unit and/or more than one dam gate can be
provided with a joint control function that controls the total water flow through the plant as well
as the water level control.
– 14 – TR 61850-7-510 © IEC:2012(E)
3.5 Hydro power plant specific information
Different devices handle active and reactive power control. The turbine governor provides the
active power control by regulating the water flow through the turbine and thus the pole angle
between the rotating magnetic flux and the rotor. The excitation system provides the reactive
power control by regulating the voltage of the generator. The magnetic flux shall correspond
to the shaft torque to keep the generator synchronised to the grid.
Figure 3 shows an example of an arrangement including a joint control function. The set-
points will be issued from a dispatch centre and could be one of three optional values.
Therefore, the type of set-point that will be used depends on the water control mode that is
used for the plant.
Active power set-point
Water flow set-point
Water level set-point
Power production
from metering
Joint power plant
control
Dam gate Governor
control control
Calculated Calculated
Upper water water flow water flow
level
Lower water
level
IEC  335/12
Figure 3 – Principles for the joint control function
In case of a reservoir without any power production, the water control function will get the
water control set-points from a dispatch centre; in case of a power plant, it will be normally
the joint control function that sets the values. The set-point will be either water level or water
flow set-points.
The total water flow is the sum of flow through turbines and gates. The turbine control system
can, due to this, be provided with different set-points for the control.
• Water flow set-point. The control system will base the regulation on the given water flow
level and try to optimise the production.
• Active power set-point. The control system will try to meet the active power, the water flow
will be reported back to the overall water control system.

Penstock
TR 61850-7-510 © IEC:2012(E) – 15 –
• Active power control with speed droop. This is the mode when the unit is contributing to
the network frequency control. The active power set-point is balanced over the speed
droop setting to obtain the desired power/frequency amplification.
• Frequency set-point. In case of an islanded system or a power plant in peak load duty, the
active power will be controlled to exactly meet the demand. This control mode is also used
during start-up of the unit, up to the point when the generator is synchronised. Water flow
will be reported.
Intake gate Water flow set-point
Net head
calculation
Water level at intake
Turbine
water flow
control
Water flow
Guide vane control
Lower water level
Under-pressure
Main inlet
valve
Tailrace
IEC  336/12
Figure 4 – Water flow control of a turbine
Figure 4 shows an example of water flow control for a turbine. Direct measurement of the
water flow, as indicated in the figure, is less common. The flow is normally calculated, using
the net head, the opening angle of the guide vanes and a correlation curve.
Main inlet valves to shut off the turbine chamber are used for pumped storage plants and
power plants with high penstocks.
It is important to differentiate between the water levels of the dam and at the intake. Due to
the intake design or if the turbine is running close to rated power, the water level at the intake
might be considerably lower than the average for the dam.
The measurement of under-pressure below the turbine chamber is a safety measure, to
ensure that the operation of the guide vanes does not cause any dangerous conditions in the
tail-race part.
– 16 – TR 61850-7-510 © IEC:2012(E)
4 Structuring control systems
4.1 Basic use of logical nodes
To fulfil all the requirements, functions are decomposed into logical nodes. Refer to Clause 9
of IEC 61850-5 for more information about the logical node concept.
The introduction of additional structures such as logical devices which are composed of
logical nodes is not an application requirement, but may be helpful for the modelling.
In order to identify the purpose of a Logical Node with a more general name, a suffix for
identification can be added. The limitation is that the sum of characters for prefix and suffix
shall not be more than 7. For use in hydropower plants, the recommended logical node
prefixes are listed in Table 2.
Table 2 – Recommended LN prefixes
Name / description of Recommended LN
function prefix
Active power W_
Actuator Act_
Current A_
Close C_
Deflector Dfl_
Droop Drp_
Flow Flw_
Frequency Hz_
Guide vane Gv_
Level Lvl_
Limiter Lim_
Needle Ndl_
Open O
Position Pos_
Power factor Pf_
Pressure Pa_
Reactive power VAr_
Runner blade Rb_
Speed Spd_
Temperature Tmp_
Unit Unt_
Voltage V_
The prefixes in Table 2 are only recommendations, the user may decide on another method to
identify the purpose of logical nodes for control functions. If a more specific definition is
required, e.g. if a flow control function is intended for water flow or oil flow, this should be
identified by the logical device name-string.
4.2 Logical device modelling
The basic standard of IEC 61850 does specify the Logical Node as the highest-level object
that has a formal structure given by the standard. However, Logical Nodes shall be

TR 61850-7-510 © IEC:2012(E) – 17 –
assembled in Logical Devices. The formal definition of a Logical Device is given in the
standard; the user is though free to select any combination of Logical Nodes that suits the
purpose.
As a simple example, we can start by looking at e.g. a pressurised oil system group
reference, used to provide initial lifting power to a vertical turbine-generator shaft.
Typically, the system would include an oil tank, a pump, various valves and oil filters. It would
also include the thrust bearing, maybe an oil sump and a number of sensors for temperature,
pressure, level and other things.
First we define a logical device group reference, or higher-level Logical Device with a LPHD
and LLN0 logical node to form a container for addition of logical devices.
Logical device group reference __PresOil
LPHD
LLN0
Looking at the complete name-string, the device name would start with the power plant name,
the generating unit name, followed by the system name; in this case “PresOil”.
This shall then be filled with the various logical devices that are required in order to create the
oil system.
The first device may be the oil tank. There is a Logical Node KTNK (in IEC 61850-7-4:2010)
that covers part of the functionality. KTNK only returns information about the level, we might
also be interested in the temperature and the pressure, so we create a logical device that
covers, beside the tank, also two pressure sensors, one temperature sensor and one
additional level sensor. A logical device shall also include Logical Nodes for common
functions e.g. LPHD and LLN0. The logical device would then be:

Logical Device Suffix Tnk
Since there are two temperature sensors, they shall be

differentiated by use of instance numbers.
LLN0
KTNK
An alternative naming could be to use a prefix in front of
TPRS1
the logical node name. The complete name-string could
TPRS2
now be e.g. _PresOil_Tnk_TPRS1 for the
TTMP
first pressure sensor.
TLVL
The same method should be used for the pressure pump.
The Logical Node for a pump, KPMP, does only report the
rotational speed. For control, we might also add a motor, a
flow sensor as well as an oil filter and at least one
temperature sensor.
Logical Device Suffix Pmp
LLN0
KPMP
In an actual application, there could be more temperature
ZMOT
sensors, e.g. one for the motor, one for the pump and one
KFIL
for the oil.
TTMP
TFLW
The filter Logical Node includes a measurement of

differential pressure over itself. If it is important, pressure
sensors could be added before and after, otherwise the
basic information is available.

– 18 – TR 61850-7-510 © IEC:2012(E)
A more tricky issue is the thrust bearing. IEC 61850-7-410 includes a logical node for the
bearing, however this could be seen as either part of the oil system or as part of the generator
shaft system.
Since any specific instance of a Logical Node only can have one address string, we s
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