Differential Protection Relay
Product Code : EL-EPP-11357
Quick Answer: The Differential Protection Relay is a relay unit that shows the characteristics of three-phase differential protection, housed in an enclosure with a carrying handle. It mounts on the desk area of the Protection and Relay Test Set or another power system product.
Last updated: October 2026
Key Features
- Three-phase differential protection relay in an enclosure with carrying handle
- Mounts on the Protection and Relay Test Set desk area or another power system product
- Multi-core cable from the back of the relay; 4 mm shrouded sockets to the test circuits
- Programmed from the keypad and display, or with the supplied software on a computer (not included)
- Functions include high stability during out-of-zone faults, zero-sequence current filtering for each winding and magnetising inrush restraint
- High-speed operation with amplitude and vector matching
Technical Specifications
| Specification | Value |
|---|---|
| Protection | Three-phase differential |
| Connections | Multi-core cable; 4 mm shrouded sockets |
| Programming | Keypad and display; supplied software |
| Computer | Not included |
| Mounting | Desk area of the Protection and Relay Test Set |
About This Product
Differential protection compares the current entering and leaving a protected zone such as a transformer winding. Students set up internal and external faults on the test set, program the relay and check that it trips for faults inside the zone, stays stable for faults outside it and holds off during magnetising inrush. The Differential Protection Relay can be supplied on export terms to Bosnia and Herzegovina, Mauritania, Iran, Bahrain and South Korea.
Frequently Asked Questions
How is the Differential Protection Relay programmed?
With the keypad and display on the relay module, or with the supplied software on a suitable computer, which is not included.
How many relays are needed for the tests?
Most tests need only one relay.
Related: Electrical Power Products, Protection Relay Test Set, Earth Fault Overcurrent Relay and Feeder Management Relay.
For a quotation on the Differential Protection Relay, contact Educational Instrument.
