IEC Contactor Terminal Numbering

Can anyone explain the system behind the numbering of terminals on IEC style contactors, motor circuit protectors, and overload relays (ie, AB 100-C, 140-M, and 193). I understand that on a starter, 13 and 14 are a normally open contact, 22 and 23 is a normally closed contact, and on an overload relay 95 and 96 are a normally closed contact, but what is the coding behind these numbers? From what I've gathered, the first number is a group and the second is related to function, but are there any rules on what number is used for a group? Is an overload always 95 and 96, or could it be 22 and 23 since it's nomally closed?

Is an overload always 95 and 96, or could it be 22 and 23 since it's nomally closed?

Click to expand...

Most overload relay i have encountered in any brand the 95 and 96 is normally closed and 97 and 98 is normally opened.

but what is the coding behind these numbers? From what I've gathered, the first number is a group and the second is related to function, but are there any rules on what number is used for a group?

Click to expand...

I dont think so or maybe they are using only to identify these numbers.

Thanks...

This might help explain it. http://www.industry.usa.siemens.com...ments/terminal-markings-white-paper_final.pdf

Christoff84 said:

This might help explain it. http://www.industry.usa.siemens.com...ments/terminal-markings-white-paper_final.pdf

Click to expand...

Mate, that's awesome. Cheers

Christoff84 said:

This might help explain it. http://www.industry.usa.siemens.com...ments/terminal-markings-white-paper_final.pdf

Click to expand...

Thanks for posting