contact resistance

simon00011 · ‎2025-02-12

which code/industry standard shows bus-to-lug acceptable contact resistance for 1KV switchgear used in Canada or US? Thanks!

Gregoire_Brun · ‎2025-02-14

hello @simon00011

Did you have this needed for a dedicated product?

It should be good to share with us a product reference.

Gregoire Brun
Breaker Product Expert

simon00011 · ‎2025-02-14

Hello @Gregoire_Brun

Please see below 2 pictures of nameplates for 2 switchboards installed in Toronto, Canada. Can you please advise the busbar-to-lug contact resistance for 2 switchboards respectively? Thanks!

Gregoire_Brun · ‎2025-02-18

@simon00011 , I'm sorry. I can't see your pictures

Gregoire Brun
Breaker Product Expert

simon00011 · ‎2025-02-20

@Gregoire_Brun

Can you see 2 attached pictures?

Gregoire_Brun · ‎2025-02-20

hello @simon00011 yes I see them now.

So if I understand well, it's some panel board make by schneider / Square D

Is it possible to have a global vue of the panel, please ?

thanks

Gregoire Brun
Breaker Product Expert

Chris1969 · ‎2025-02-22

I'm not aware of a standard outside of any specific manufacturer recommendations. A lot of variables determine the actual value measured. For high ampacity conductors with highly conductive contact surfaces, measurements in single digit micro-ohms is the goal.

ANSI-NETA ATS and MTS provide procedures for visual and mechanical inspections, and electrical tests for finding high resistance connections in electrical systems, and specifically bolted electrical connections. There are also explanations of acceptable test values. From the ANSI/NETA MTS 2015 edition, reference 7.1.A.7 and 7.1.B.1 and 7.1.C.1 and 7.1.D.1.