Lockout Relay - ANSI 86

Yes,

You are right. The Relay provides lockout function and needs to be reset manually or through one of the inputs poinsts of SR750 to enable closing of breaker once again.

However, please be careful when you use the SR750 contacts directly to trip the breaker since repeated use of this contact for breaking the trip coil may lead to deterioriation of the contact due to high inductive property of the breaking coil. Your design needs to address this particular issue.

Regards,

Balaji - www.protecsol.in

86 relay can be :

1. One of Functions in Multilin (Digital Protection relay),

2. A conventional relay (coil relay), that have form like selector switch (we can rotate the handle).

this relay works like other relay, if coil energized, NO contact become NC and vise versa. But once it energized, we must rotate the handle to reset it.

Sometimes, in some plant. to increase the safety of the system, it uses 2(two) 86 relay, installed seriesly. one 86 relay of Multilin & one 86 Conventional relay.

86 conventional relay is used to guarantee if Multilin has a problem.

In most designs , you will use a separate lockout relay (86) to do all trip lockouts.

Depending on the Multilin or other electronic relay to do the lockout is a bit risky.

Lockout relays 86) usually have a trip coil and a reset handle giving positive lockout and needing a definite manual turning of the reset handle to reset.

The contacts on the lockout relays can usually handle up to 30 amps easily and also has lots of spare contacts for sending indications to lamps and control systems ,SCADA etc.

Thanks so much. All replies are so helpful. Now I know what I have to do.

- MS