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110v Electric motor with led

  1. Jan 24, 2010 #1
    In the machine shop where i work they have a coolant system that runs separately from the CNC machine. As of now, they simply plug in the motor and it turns on, however they often forget to unplug it at the end of the day. I need to wire a toggle switch and and LED indicator for when the motor is on. I need a simple diagram of how to wire in the switch and LED, and i need to know what size (voltage/amperage) of switch and LED to use so they arent burned out by the 110v. PLEASE HELP!!
  2. jcsd
  3. Jan 24, 2010 #2


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    You would normally use a neon bulb rather than a LED, you can buy indicator bulbs with a built in resistor that you just connect across 110V
  4. Jan 24, 2010 #3
    yeah thats what im seeing on other sites, seems a neon has a much higher current and voltage cpability. As far as the switch goes, should i use a toggle switch or a circuit breaker dince there is high current running through it? thanks by the way, really appreciate the help!!
  5. Jan 24, 2010 #4
    The neon or LED (with appropriate resistor) would need to be rated for 110V but would draw only a small current. The switch or circuit breaker would need to be rated correctly for the motor concerned.

    Having said that, only appropriately qualified personnel should modify electrical installations. Such work should only ever be done according to the relevant laws and regulations. In most circumstances, you would need to be a qualified electrical engineer or electrician to be allowed to do what you are suggesting.

    A suitably qualified person would not need to ask how to go about this task, so please do not try to do this yourself. In addition, you must not tamper with equipment which is not your property without consent of the owner, or whoever is in charge of it at your work. If you can persuade your employer that this is a good idea, perhaps he/she can get a qualified electrician to do the job?
  6. Jan 24, 2010 #5


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    I was thinking that he could use a simple lighted, switched power strip that is rated high enough for his motor. Just plug it in. No problem.
  7. Jan 24, 2010 #6
    Switch strips with shuttering & IP rating OK to cope in an environment with soluble oil emulsion splashing everywhere, and swarf / metal chips flying about?

    Is the switch on that strip OK to break a motor of unknown rating, perhaps quite inductive and inclined to make the switch arc?
    OK for use by an operator with wet hands, perhaps standing on wet concrete floors?

    Then, is the pump on a wall socket in the first place? This is best left to the experts, I think
    Last edited: Jan 24, 2010
  8. Jan 24, 2010 #7
    Oops, sorry, on re-reading the original post it says that:
    I have to admit therefore that a plug-in adaptor would be possible, but it still doesn't seem a good idea.

    Apart from the points already mentioned, what about the extra length of trailing cable? Machine shops are dangerous places already without introducing an extra trip hazard.
  9. Jan 25, 2010 #8
    im not going to be the one doing the install, they just asked me about what switches and lights to use. i suggested a power strip but they want something on the machine or closer to the door so they can see it when they leave. the outlet itself is rather hidden from view. i mostly deal with small power electronics and sometimes like to be sure when dealing with 110v. what about putting the switch on the other side of the transformer on the motor, there would be less current and voltage on the motor side of it.
  10. Jan 25, 2010 #9


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    Toggle, properly packaged, is fine. You should probably be able to buy the switch and indicator as a pre-packaged set. The breaker on the other end of the wall plug is fine for fault interruption.
  11. Jan 25, 2010 #10
    A completed package would be ideal for install, where do you suggest getting these? I 've checked with our suppliers and they have nothing of the sort.
  12. Jan 25, 2010 #11


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    Last edited by a moderator: Apr 24, 2017
  13. Jan 26, 2010 #12
    thanks for everything, i think i have what i need to give the guys now.
    found a rocker switch with a built in neon next to it, rated at 125VAC and 16amps from action-electronics.com
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