Can you identify this power switch?  - Page 1
Forum section: electronics / beginners

author: Infidel
author_rank: Newbie
timestamp: May 06, 2020, 12:51:11 pm
content: I'm trying to repair the power switch from a coffee machine and have searched my eyes out for something like it. What worries me about replacing it with a simple round switch is that I see what I suppose is a resistor in there.

author: Jwillis
author_rank: Super Contributor
timestamp: May 06, 2020, 01:45:42 pm
content: Is that a neon bulb inside ?

author: WattsThat
author_rank: Frequent Contributor
timestamp: May 06, 2020, 02:24:50 pm
content: Quote from: Jwillis on May 06, 2020, 01:45:42 pmYes, that’s why the resistor is in there. The orange glow of an old fashioned ionized gas solution. One cent resistor + one cent neon lamp = 2 cent pilot lamp. Hard to beat, especially when it’s built into the switch housing. What you’ve got there is 100% custom.

author: ArthurDent
author_rank: Super Contributor
timestamp: May 06, 2020, 02:29:13 pm
content: That is indeed a neon bulb inside and the 150K ohm resistor is in series with the neon bulb. The red dot on the black button looks like it's a colored lens that the neon bulb can shine through. It is a line switch with a 'on' indicator. There are many different shapes and sizes on eBay like the one mentioned below. Finding one exactly like the original will be unlikely so it will depend on how much room you have to mount a replacement switch. If the switch is to be used on 240VAC you'll need a switch with a lamp rated for that voltage or use a 120VAC model with an external approximately 75K ohm resistor in series with the internal resistor to limit the current to the lamp to a safe value.https://www.ebay.com/itm/1-PC-SPST-ON-OFF-Rocker-Switch-w-RED-Neon-Lamp-20A-125VAC-USA-SELLER/291676726480?hash=item43e949a4d0:g:-Z0AAOSwUKxYhvHm

author: WattsThat
author_rank: Frequent Contributor
timestamp: May 06, 2020, 02:50:02 pm
content: If it were mine, I’d bust that puppy open and see what I could do to refurbish it. I’ve been know to make FrankinSwitches out of old relay contacts. When you can’t buy it, make it.

author: Infidel
author_rank: Newbie
timestamp: May 06, 2020, 03:47:31 pm
content: I think that would be way beyond my capabilitiesFrom what you said I'll look for a switch with the same specs that fits.It is from his coffee machine, btw:https://www.melitta.kr/en/Linea-Unica-878.htmlThank you for your help!

author: Gregg
author_rank: Super Contributor
timestamp: May 06, 2020, 05:03:32 pm
content: I got tired of replacing power switches on my old espresso machine and installed a heavy duty relay for the heating elements so that the power switch only has to switch the much lower current of the electronics and the coil of the relay.You may be able to clean up the existing switch contacts enough that it will work without the high current load of the heating element.

author: Infidel
author_rank: Newbie
timestamp: May 07, 2020, 09:34:23 pm
content: The switch itself actually works. The problem is that the little hinges seen in the first and second picture broke.They were what held the switch inside the machine and the button on the outside in place. You could glue the switch into position, but the button would still fall off.

author: Jwillis
author_rank: Super Contributor
timestamp: May 08, 2020, 07:32:12 am
content: What is the diameter of the button. If your friend isn't concerned about exact match maybe a round 250V rocker switch might just fit the button hole diameter.