Merlin Gerin NS breakers (protection)

[cctdiag]

Could somebody explain the Io adjustment pot on the NS breakers I have fitted. Some of my units have this faclity and others dont?

Jeff

 

[MDom]

cctdiag, Io designates coarse adjusment ( function of In),Ir - fine adjustment - both for long time protection against overloads for electronic trip unit STR 22SE,22GE,
23SE,43 ME,53UE.The adjusment is defined as multiplication Io x Ir.
But if you have NS with termal magnetic trip unit TM-D or TM-G the adjusment of overload protection is chosen only by one pot - Ir ( rated as 0.8, 0.9 and 1 of nominal current indicated in Amps). Im in TM trip unit as for electronic indicates magnetic protection against short-circuit.
The same for motor protection trip unit STR 22ME - you have only one adjusment Ir rated in Amps for long time overload protection.
The tripping time of overload protection:
CB will trip within 2 hours for a current equal to
120% of Ir for electronic trip units
130% of Ir for thermal-magnetic
CB must not trip for a load under 105% of Ir.

 

[cctdiag]

MDom, Many thanks, this also identifies which are the magnetic and the electronic trips for me.

cctdiag

 

[don01]

jeff
mdom seems to have covered it very well ( I wonder if he /she works for them ??)
as a suggestion give your local MG rep or reseller a call and lean on him MG have some excellent publications on their gear.

Regards
Don

 

[MDom]

don01,you are right I work for Schneider in Russia
cctdiag,I can propose

http://www.squared.com/us/products/

or

http://www.schneider-electric.com

for more information about
Compact NS
Best regards