I'm replacing the motor control switch in this toaster and wanted to be certain about how it should be installed. It's a normal SPST neon rocker switch with A, B and C for terminals, and B-C being for the neon. It would simply be 1-A, 2-B, 3-C, correct?
m83 schematic

Hopefully I wasn't too vague and I can provide more details if needed. Thank you for your help!

  • \$\begingroup\$ I think you may mean SPDT \$\endgroup\$ – Andy aka Jun 29 '15 at 11:56
  • \$\begingroup\$ @Andyaka The motors are hard-connected to one of the incoming voltage wires, so the OP's correct in his(/her? it happens these days, luckily) SPST+Neon assumption. \$\endgroup\$ – Asmyldof Jun 29 '15 at 12:24

To the schematic: JEEZ! Way to make a maintenance schematic that invites making stupid errors.

To your assumption/question/check: Yup. (after what felt like a year tracing hoppy black lines)

The top, 1, comes from mains White through the relay. The middle, 2, goes to the motors to turn them on. The bottom, 3, is connected to the mains Black. Since your motors are also directly connected to mains black, it's not a reversal switch. So you only need SPDT if you need to hard-brake them, which seems unlikely to me in the case of butter and bread transport (low inertia).

So the bottom pole is most likely for the Neon light, which turns on then A and B (1 and 2) are connected by the switch itself.

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  • \$\begingroup\$ Yeah haha that was part of my problem. Toaster at work stopped working, and the electrician my boss called showed up one day, moved toaster to back, took off the side panel, said the AC gearmotor was dead and hasn't shown back up in over a week. The switch that turns the motor on was full of burned butter and had two holes in the side where it burned through, so I bet motor is fine and switch just wasn't turning on anymore. Tracing the schematic in colors last night helped a bit too lol. Thank you! \$\endgroup\$ – utopiated Jun 29 '15 at 20:53
  • \$\begingroup\$ @utopiated Hope it fixes it. Sometimes motors break and that in turn melts switches. But, if you are careful in the sense of maybe adding a fuse in line with the switch you will be able to keep using the switch if it turns out you need to fix something else too. If you put a fuse of half the rated switching current between point 1 and switch terminal A, that should keep it safe, also from flames during testing. If the fuse breaks, you can do a careful try with one at the rated switching current, but if that breaks, more measurements of motors is needed. \$\endgroup\$ – Asmyldof Jun 29 '15 at 22:51
  • \$\begingroup\$ That's a very good point. I think I should have a fuse that'll work in my toolbox somewhere. I'll also check the current draw with my clamp meter and compare it to the motor spec to see if it's drawing more than it should as well. \$\endgroup\$ – utopiated Jun 30 '15 at 5:24

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