Air Compressor for EngravingEvery once in a while we will receive a call or email from one of our customers that is having trouble with their compressor shutting off during use. If they are at an engraving event, this is a BIG PROBLEM. The last thing we want is for your engraving equipment not to work properly while you are in front of customers at an event.

Here’s the Situation – The Compressor is Getting Hot and Turns Off

You’re engraving away and all of a sudden your compressor shuts off. It won’t turn back on and if it does, it will only stay on for a short time before it shuts off again. It feels HOT. Once it cools down, it will turn on again but then this same scenario repeats as the heat returns.

Luckily, this is an easy fix 99% of the time.

Here’s How to Avoid Your Compressor Turning Off

  • Plug the compressor directly into the wall outlet
  • Do not plug it into a Power Strip
  • Do not plug it into an extension cord (see below if you HAVE to use an extension cord)
  • If you must use an extension chord, make sure it’s a 12 gauge cord (12 gauge is the thickness of the wires) and not excessive length. The size of the wire used in the extension cord will be stamped or moulded on the cord (AWG). If the cord is labeled 12/3 – that means it is 12 gauge wire and has 3 wires.  Here is a good article on this if you want more explanation.
  • The longer the extension cord, the larger the wire will need to be in order to deliver enough power to the compressor. The longer the extension cord, the more heat will be generated during use. Therefore, use a shorter extension chord when possible. Buy Quality – Cheap extension chords are not worth the risk!

Power Strips – Most Power Strips have small wires in the cord. Even though the length is usually very short, if the wire is undersized, this may cause your compressor to over heat. Go ahead and plug your lights, etc. into a power strip, but plug your compressor directly into the wall outlet.  This will eliminate the problem of the compressor overheating and turning off.

Best Practices

  • Get a good 12 gauge extension chord and take it with you to every engraving event.
  • Only use the extension cord for your compressor if you HAVE to and don’t use one that’s too long – the shorter the better.
  • Never plug your compressor into a power strip or extension cord with undersized wire.
  • Go ahead and use a power strip for your table lamps, desk lamps, etc.
  • If your compressor overheats, wait for it to cool down completely before operating to avoid damaging the compressor.

Here’s the Explanation of the Problem

Compressors, including the Thomas Quiet Compressor for Engraving, require quite a bit of power to operate.

Power is delivered to the compressor through the power chord. If the size of the power chord (or extension chord) is too small, the compressor cannot get enough power and therefore has to work harder in order to do it’s job. The by-product of this situation is HEAT. The compressor eventually overheats due to the lack of power.  Luckily, quality compressors (like the Thomas Portable Compressor) have built in thermal protection which turn off the motor before damage occurs from heat. When the compressor gets too hot, the thermal protector will not allow the compressor to turn back on until the motor cools down to a safe operating temperature. This is a good thing – it’s protecting from further damage.

A common mistake we see is when the compressor is plugged into a power strip. We understand that most people use power strips in order to have more outlets to run lights, etc. while they are engraving. Power strips are great but they’re not great (at least most of them) for powering compressors and other things that require more power than the tiny wires inside the power strips can pack.


Be prepared when engraving at live events. Prepare for situations when you might be far away from a power source or even a building with poor electrical wiring. Invest in good equipment including extension cords and always have a back up of those components that might fail (I never do an event without having at least a spare cartridge with me).

If you have any questions, please Contact Us.