Question about NO on Emergency Stop Button

My main power is running through the NC (Normally Closed) portion of the Emergency Stop Button (V1 purchase). I took the switch apart at one point, to learn about it and am wondering if I reassembled it properly. The NC works fine, but you have to press really hard (passed where it properly latches), to make electrical contact for the NO (Normally Open). When you release the pressure electrical contact is no longer made. Should the NO latch and provide constant continuity when the button is locked down after being pressed? If so, I can just buy another button. Thank you.

Most people don’t use the NO side of the switch. As long as the NC side breaks contact when the button is latched, then you can use your switch. Of course this assumes you don’t have some special use for the NO side of the switch.

I do have a special use for the NO side. The NC is also hooked up, which is electrically isolated from the NO side (learned from taking the switch apart). I was hooking it up to a GPIO pin on a Raspberry Pi. Actions could be taken based on whether the Emergency Button was depressed. I was hoping someone had a spare around and hook up their DMM to the NO side and do a continuity test when the button was up and latched down.

If your switch is the type where it needs to be reset by pulling it back out, etc, then yes the NO should be closed while the NC are open. Then the NO should be open when the NC are closed. If this is not the case, you may have reassembled your switch contacts incorrectly when you took it apart, or something in the switch is not right.

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I can confirm that the NO side does make continuous contact after the button is pushed. The video that you linked mentioned the little windows through which you can view the contacts, but he didn’t show them specifically.

This is what I see on the NO side after the button has been pressed, and you can see the contacts touching.

@Mattk331, @jamiek ,

Thank you very much for verifying that. I tried taking it apart and fixing it, but it still isn’t correct. I will buy a replacement and test them (without disassembling them), before installing them into my control case. Again, thank you very much.