Voltage selection relay 1

[HiSet]

we have an application wherein under voltage load shedding scheme needs to select 3 phase voltage from one of possile three line VTs.Can some one suggest a voltage selection relay capable of accepting three sets of three phase voltages?

 

[ScottyUK]

What are the selection criteria? Or are you looking for continuous monitoring of three sources?


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If we learn from our mistakes I'm getting a great education!

 

[slavag]

Hi.
That menas 9 voltage inputs and few 3-ph/1-ph undervoltage protection function for every set.
I don't know such simple relay, only high class terminals, like to ABB REC670, but it's overkill, from my point of view. From other hand, its an load shedding, maybe you need some additional logic and load monitoring.

Please give more information.
Best Regards.
Slava

 

[jghrist]

Maybe you could use 3 voltage relays and a PLC, or maybe two simple voltage relays and one with some logic capability. I'm curious about the load shedding logic. If the line breakers are closed, then the line voltage is the same as the bus voltage. If a line breaker is open, what would the undervoltage load shedding do with this line?

 

[waross]

What jghrist said.
Also consider three voltage monitor relays and a smart relay.

http://www.idec.com/usen/products/Catalogs/SmartRelay/FL1D/overview.html

http://www.siemensplcweb.com/a/Siemens_PLC/2009/1221/3.html

Bill
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