Application Note

Self-Powered-Relay (SPR) takes its supply from the  CT-s connected and also the energy for tripping the breaker. SPR  either has special CT made for the relay or is made to be used directly with standard CT-s.

There are differences in how to set Sverker 900 when testing SPR that must be noticed.
1. The level of pre-fault current and time needed for pre-fault.
2. The pickup level for trip signal if not dry contact is used.

Here secondary testing of SEG relay (formerly Woodward) WIP1 and WIC1 will be described.

Application for Testing Self Powered Relays SEG (Woodward) WIP1 and WIC1