LSIG breakers

[bozzah]

I am trying to find more info regarding LSIG breakers in general (operation, settings, general theory, etc). Any good web links or books?

thanks.

 

[Zogzog]

Thats a pretty broad topic, I teach a 40Hr course on the topic. What exactly are you looking for?

 

[bozzah]

I have seen LSIG (Long short instantenous ground) breaker on low voltage system (480V or 600V).
At what service (V and I) they are required (i.e. commonly used) and why?
Are they appropriate for settings, that is can you play with the tripping curves?
Do we have to go with LSIG or LI/LIG breaker would be ok ...or a typical breaker contains all options generally and one would set it up to suit?

thanks.

 

[Zogzog]

A short circuit and coordination study is required to determine the settings, you dont play with the curves/settings.

 

[bozzah]

It is required, I understand.
I am not trying to touch on that topic. For example, moulded case CB are "fixed" and my question was can you manipulate with setting for LSIG as I am trying to get more understaning of LSIG?
Thanks for the abundant response.

 

[Zogzog]

Sure you can change the pickup and or delay settings. Here is a simulator program that you can play with the settings.

http://www.utilityrelay.com/ACProSimProg.htm