Design of Sudden Pressure Relay Blocking Scheme for Transformer
Design of Sudden Pressure Relay Blocking Scheme for Transformer
(OP)
How to design SPR blocking scheme using 63 and 50 Fast instantaneous over current element?
Is SPR used for tripping the relay for internal faults only?
How will it block tripping if 63 contacts are short because of transient?
The logic I'm having in my mind is= 63A And not 63B not 87 not 50) will trip the relay , is my thinking correct?
Is SPR used for tripping the relay for internal faults only?
How will it block tripping if 63 contacts are short because of transient?
The logic I'm having in my mind is= 63A And not 63B not 87 not 50) will trip the relay , is my thinking correct?





RE: Design of Sudden Pressure Relay Blocking Scheme for Transformer
If you have an energize-to-trip scheme, you'll need a normally closed contact in series with the 63 tripping contact ("a" contact) that will open during whatever conditions you want to block.
The differential 87 trip contact should not be blocked.
David Castor
www.cvoes.com
RE: Design of Sudden Pressure Relay Blocking Scheme for Transformer