Overview
The E2-TR is a dedicated two-winding transformer protection and control IED; the relay provides complex protection, control and monitoring functions for two-winding power transformers. It is member of the DTRV product type in the EuroProt+ product family.
The DTRV type is designed particularly for protection and control applications of power transformers and generators including generator-transformer blocks. Additionally, the DTRV product type includes a variety of versatile protection functions to meet the users´ most exacting requirements.
Because of the implemented control, measuring and monitoring function, the IED can also be used as a bay control unit.
The EuroCAP configuration tool, which is available free of charge, offers a user-friendly and flexible application for protection, control and measurement functions to ensure that the IED-EP+ devices are fully customisable.
General features
- Native IEC 61850 IED with Edition 2 compatibility
- Scalable hardware to adapt to different applications
- 84 HP or 42HP wide rack size (height: 3U)
- The pre-defined factory configuration can be customized to the user’s specification with the powerful EuroCAP tool
- Flexible protection and control functionality to meet special customer requirements
- Advanced HMI functionality via color touchscreen and embedded WEB server, extended measuring, control and monitoring functions
- User configurable LCD user screens, which can display SLDs (Single Line Diagrams) with switchgear position indication and control as well as measuring values and several types of controllable objects.
- Various protection setting groups available
- Enhanced breaker monitoring and control
- High capacity disturbance recorder (DRE) and event logging (data is stored in non-volatile memory):
- DRE for up to 32 analogue and 64 digital signal channels.
- Event recorder can store more than 10,000 events.
- Several mounting methods: Rack; Flush mounting; Semi-flush mounting; Wall mounting; Wall-mounting with terminals; Flush mounting with IP54 rated cover.
- Wide range of communication protocols:
- Ethernet-based communication: IEC61850; IEC60870-5-104; DNP3.0 TCP; Modbus TCP
- Serial communication: DNP3.0; IEC60870-5-101/103; MODBUS, SPA
- The EuroProt+ family can handle several communication protocols simultaneously.
- Built-in self-monitoring to detect internal hardware or software errors
- Different time sources available: NTP server; Minute pulse; Legacy protocol master; IRIG-B000 or IRIG-B12X
Application
The E2-TR is a dedicated two-winding transformer protection and control IED; the relay provides complex protection, control and monitoring functions for two-winding power transformers. It is member of the DTRV product type in the EuroProt+ product family.
The E2-TR relay provides a variety of versatile protection functions along with the main transformer differential protection, such as 3ph, Io and I2 overcurrent protection, overload protection, restricted earth-fault protection etc.
Sensitive restricted earth-fault protection (REF) is the final element in the overall differential protection system, which detects even single phase-to-ground faults close to the grounded neutral of the transformer.
The multiple instances of the implemented three-phase and residual overcurrent functions are provided for the segregated protection of both transformer windings.
Furthermore, several voltage-based protection functions are available for one transformer winding based on the three-phase voltage measurement. The connections of the voltage measurement depends on the current application.
The E2-TR transformer protection relay can support double-breaker terminals on any side of the transformer such as breaker and a half or ring bus topology.
Automatic phase shift and turns ratio compensation for all types of transformer winding connections.
It can be used as a back-up protection relay for downstream equipment (e.g. feeders, cables).
The IED includes a wide range of control and supervisory functions, which provide full control and user-defined interlocking schemes for the primary switchgear at the substation.
scope of application
- 2-winding transformer protection and control device with main transformer differential protection and several additional protection functions;
- The versatile protections functions can provide back-up protection relay for downstream equipment (e.g. feeders, cables etc.),
- Protection for all kinds of power transformers (including auto-transformers),
- 1-/3-phase tripping and support for double breaker terminals such as breaker and a half or ring bus topologies
- Three-phase transformer differential protection:
- Automatic phase shift and turns ratio compensation of the transformer,
- 2nd and 5th harmonics restraint for transformer inrush and overexcitation detection,
- Residual current elimination feature is available if there is a neutral grounding transformer in the protected zone on the secondary side of the transformer,
- Sensitive restricted earth-fault protection,
- Several voltage-based protection functions are available through the three-phase voltage measurement,
- Current unbalance detection of Current Transformers,
- Programmable interlocking schemes,
- Optional external units:
- 28 input/ 5 output tap changer transcoder (TRCS),
- Remote I/O unit (RIO),
- Optional transducer I/Os (RTD/mA),
- Optional impedance protection
Protection & control functions
The E2-TR configuration measures three phase currents, the residual current component from both sides of a two-winding, three-phase transformer and, additionally, three phase voltages. These measurements allow, in addition to the current- and voltage-based functions, directionality extension of the residual overcurrent function.
The main protection functions are the transformer differential protection and the restricted earth-fault protection functions. Based on the voltage measurement, the frequency is also evaluated to facilitate frequency-based protection functions.
The additional protection functions can provide back-up protection relay for downstream equipment (e.g. feeders, cables etc.).

| Protection & control functions |
IEC |
ANSI |
*Inst. |
|
|
|
| Differential Protection Function (versions 5 and up on 2.10 systems) |
3IdT > |
87T |
1 |
18/12/2024 |
|
|
| Overexcitation protection function |
V/Hz |
24 |
1 |
20/12/2024 |
|
|
| Definite time undervoltage protection function |
U<, U<< |
27 |
2 |
19/12/2024 |
|
|
| Negative sequence overcurrent protection function |
I2> |
46 |
1 |
04/04/2025 |
|
|
| Negative sequence definite time overvoltage protection function |
U2 > |
47 |
1 |
10/10/2024 |
|
|
| Line thermal protection function |
T > |
49 |
1 |
03/01/2025 |
|
|
| Three-phase instantaneous overcurrent protection function |
I >>> |
50 |
2 |
17/01/2025 |
|
|
| Residual instantaneous overcurrent protection function |
Io>>> |
50N/50G |
2 |
09/12/2025 |
|
|
| Breaker failure protection functions |
CBFP |
50BF |
2 |
03/10/2022 |
|
|
| Three-phase time overcurrent protection function |
I>, I>> |
51 |
2 |
04/04/2025 |
|
|
| Residual overcurrent protection function |
Io>, Io>> |
51N/51G |
2 |
04/04/2025 |
|
|
| Definite time overvoltage protection function |
U>, U>> |
59 |
2 |
19/12/2024 |
|
|
| Residual definite time overvoltage protection function |
Uo>, Uo>> |
59N |
2 |
20/12/2024 |
|
|
| Current unbalance function (CT Supervision) |
|
60 |
2 |
20/12/2024 |
|
|
| Directional residual time overcurrent protection function |
Io Dir>, Io Dir>> |
67N/67G |
2 |
03/12/2025 |
|
|
| Overfrequency protection function |
f>, f>> |
81O |
2 |
20/12/2024 |
|
|
| Underfrequency protection function |
f<, f<< |
81U |
2 |
20/12/2024 |
|
|
| Rate of change of frequency function |
df/dt |
81R |
2 |
20/12/2024 |
|
|
| Restricted earth-fault protection function |
REF |
87N |
2 |
10/12/2024 |
|
|
*The INST. column contains the numbers of the pre-configured function blocks in the factory configuration.These numbers may be different in order to meet the user’s requirements.
Documentation
Product Configuration Options
| IEC61850 documents |
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TISSUEs Implementation Conformance Statement (TICS) for the IEC 61850 Edition 2 server interface in Europrot+ product family
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18/04/2023
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Protocol Implementation eXtra Information for Testing (PIXIT) for the IEC 61850 Edition 2 server interface in Europrot+ product family
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18/04/2023
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Protocol Implementation Conformance Statement (PICS) for the IEC 61850 Edition 2 server interface in Europrot+ product family
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18/04/2023
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Model Implementation Conformance Statement (MICS) for the IEC 61850 Edition 2 server interface in DTRV product
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18/04/2023
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Protocol Implementation eXtra Information for Testing (PIXIT) for the IEC 61850 Edition 1 server interface in Europrot+ product family
|
09/07/2019
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Protocol Implementation Conformance Statement (PICS) for the IEC 61850 Edition 1 server interface in Eurorot+ product family
|
09/07/2019
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Model Implementation Conformance Statement (MICS) for the IEC 61850 Edition 1 server interface in the Eurorot+ product family
|
09/07/2019
|
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| Type description |
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Transformer protection & control
|
18/07/2025
|
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| Hardware Guides |
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Hardware description
|
31/07/2026
|
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Maintenance guide
|
28/06/2023
|
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| Application Guides |
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Operating Manual and Troubleshooting Guide - system version: 2.8
|
02/10/2023
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| Configuration Descriptions |
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E2-TR configuration description
|
09/07/2019
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E2-TR_H product configuration options
|
05/08/2026
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E2-TR_F product configuration options
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05/08/2026
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