Testing Digital RelaysTesting multi

Testing Digital Relays
Testing multifunctional digital-transformer relays offers some unique challenges to the user.
Multifunction relays have protective functions that interact with each other, making testing more complicated.
They can also be programmed to do control logic, which must be verified. In addition, digital relays can have multiple setting groups that may be switched to address varying system conditions.
This flexibility increases the commissioning complexity.
These relays also have significant input monitoring capabilities that can greatly assist the user in determining whether these relays are properly connected to their CT and VT inputs, helping to verify that the relay is functioning properly.