Multilin 750 Logic

[cherry2000]

We have seperate Transformer Mechanical Alarms being hard wired to Logic Inputs in SR 750 relay (Logic Input 3 through Logic Input 7). See attachment.
We want to develop an "OR" logic within SR 750, so that in the event of any of these Mechanical Alarms going high, a common target relay needs to go high. We then want to read the status of this common relay as "Transformer Common Trouble" in Modbus ( RS485 link has alrady been established between DCS & the relays ).
Is it possible to do this? If yes, how....

 

[dpc]

Outputs 3 through 7 are auxiliary outputs that can be programmed operate from any of the user inputs, I believe. Refer to the relay manual.

You'll probably have to take care of the name of the alarm on the other end of the Modbus cable. I suspect you may be able to re-map the Modbus register to a user register as well.

The 750 is getting a bit long in the tooth and has fairly limited configuration/programming options compared with present generation protective relays.