86 protection 5

[pisimatza]

I want to learn what is a lockout relay-86.
Is just equivalent to a reset button?
Thank U.

 

[jghrist]

86 relay sends "Open" command?
I thought it sends "NO close until reset" command?

Relay does not "send" commands. It has several normally open (NO) and several normally closed (NC) contacts. You put a NO contact between the dc+ bus and the breaker trip coil so that when the 86 trips, it trips the breaker. You put a NC contact between the closing contacts and the breaker close coil so that when the 86 trips, the closing contacts cannot close the breaker (locked out).

 

[cranky108]

Neet a lockout with communications abilities.

I still perfer hard wired.

 

[RRaghunath]

slavag,

Sorry for delay. I haven't been on forum for a few days.

I work for one utility and the electrical reset from SCADA control room is the practice here for 132kV OHLs.
The operator in SCADA control room has discretionary powers to reclose (one time) the tripped line after resetting the 86 from SCADA.

 

[slavag]

Thank you Raghun.
I work now for some utility too and first time see this option of electrical reset from SCADA.
Regards.
Slava

 

[c4xpower]

Hi all,

In our utility we use Alstom MVAJ type protection lockout relay, mainly for transformer protections eg bucholtz. Relay uses N/O contacts to trip CB, and N/C contacts to break the closing supply. These are hand reset relays, but do use a spare N/O contact to signal SCADA that protection is locked out. Due to the nature of the faults involving transformers, you would never want to reclose without first carrying out a site investigation therefore these relays are hand reset only.

 

[oldfieldguy]

I am rather partial to the GE "HEA" series of auxiliary relays. They trip electrically and are reset manually. You can order them with a number of different configurations aof contact genders (NO/NC) and numbers of each. I particularly like the fact that by removing a cover held in place by one thumbscrew, you can SEE which contacts are opened and closed at a particular time.

Electroswitch makes a common version also, but the contacts are enclosed. Electroswitch makes versions with electrical trip AND reset.

old field guy