Klixon thermal protection

Discussion in 'General Electronics Chat' started by Gdrumm, Mar 8, 2010.

  1. Gdrumm

    Thread Starter Distinguished Member

    Aug 29, 2008
    I'm working on a dead paper shredder, and have come across a Klixon 17 AM thermal fuse. I've read the onfo on their site, and understand it's auto-reset capability. I've checked it for conductivity, and it checks out fine.

    I've jumpered the two interlock switches (paper feed and waste can proximity, so they are not the issue).

    I was able to jumper one motor brush, and then one lead of the Klixon get the motor running, but I don't understand why it doesn't work without that jumper.

    Is it possible that it tests good with a low voltage conductivity meter, but then instantly kicks out when 110v is applied?

  2. Gdrumm

    Thread Starter Distinguished Member

    Aug 29, 2008
    Fixed it already.

    I had an old thermal fuse from a different device (also a Klixon), so I wired it in, and everything works perfectly now.

    So, problem solved, and the obvious answer to my question is yes.

    At low voltage (1.5v DC) the conductivity meter shows it to be good, but as soon as you put it under 110v load, it kicks out.

    So, to quote the famous talk show host Mark Levin, "Thank me very much"

  3. BillB3857

    Senior Member

    Feb 28, 2009
    13 minute fix! Great job.
  4. retched

    AAC Fanatic!

    Dec 5, 2009
    I was gonna suggest checking the voltage across the fuse when properly energized..

    But yes, that was a quick fix.
  5. novastan

    New Member

    Mar 11, 2010
    About the Klixon thermal breakers, I had two go bad on a camper unit hot water heater last year. The camper quit giving hot water, so I opened up the little control box mounted on the side of the tank. Found two Klixon thermal breakers mechanically pressed against the tank in line with the heater coil. The heater coil was not getting 110vac so I removed both of the Klixons. one was erratic and the other one was stuck open.

    I never realized that a 'Thermostat Controller' could be made out of these. One Klixon was marked 120F or kinda like that. The other one was marked at something like 165F or there abouts. My memory getting kinda bad. But I thought that was a clever use of those things. Anyways, I replaced both with a replacement kit from the RV supply house. Worked fine since.

    I guess if the first one (120F) failed (stuck closed), the second one (165F) would save the tank as a safety measure. I suppose one would realize something was wrong as soon as scalding and steaming water started coming from the hot water tap.