Snap Action Breaker polarity?

I received a shipment of 15A snap action breakers yesterday, and I noticed that each has one brass-colored terminal and one copper colored terminal. (OBTW, they’re on sale at AndyMark.)

There doesn’t seem to be anything on the info sheet for the breaker about polarity. Does anyone know if there is a preferred polarity, or if not, why the terminals have different colors?

I don’t believe they had a polarity.


IIRC, their polarity is “metal into slots, plastic sticking out”.

I’d guess that the different colors have something to do with the action part of snap-action but I’m not sure on that.


Don’t believe there is an electrical polarity however the one in your post is mechanically asymmetrical and the PDP indicates a suggested way they should be inserted but again, ’ don’t believe it makes a difference.

I agree with Eric’s theory.

as said above, i don’t see any particular reasons for the two different metals, it shouldn’t make a difference polarity wise though

I’d wager the use of the two different metals is in connection with some kind of bi-metalic strip-like mechanism for the “snap action” trip.

EDIT: I am nearly certain that between the PDB, PDP, and Spike Relays, I have installed the breakers each way relative to the electron flow.


Wiki simple: They don’t have a polarity

If polarity was important it would be marked on the breaker and on the data sheet.

1 Like

Take one apart, and you’ll probably figure it out.

1 Like

Hey, got curious myself and messaged snap action, heres their reply


Thanks, @NoahE07_6656!

OBTW, the 15 A breakers on sale at AndyMark have rather short (0.2533") terminals, not the 0.57" of the ATO/ATC breakers typically used in FRC. (And too short for some fuse panels I bought.)


@GeeTwo Thanks for pointing this out, we got those for a custom project and had some extra. Sorry for not having a detailed description, I understand the confusion and have updated the page.
(Our inventory software says they are actually the 0.25" terminal version, which makes sense as we were soldering them to a PCB, but I will measure them on Monday to be sure we got what we ordered)

1 Like

This topic was automatically closed 365 days after the last reply. New replies are no longer allowed.