Versalaser compressor danger

Recently the computer controlled air assist unit for our Denford supplied versalaser vl200 laser cutter stopped working.

We took it apart to confirm that it was dead, inside the housing is a rocking piston compressor motor, an air cooling radiator, a water trap unit and solid state relay controlled by a small USB connected micro controller unit. This board is what turns the compressor on and off as called for by the software.

The motor was jammed solid and hooking it directly up to the mains via a plug didn’t change things.

The most worrying thing though was the damage to the internal hoses caused by them rubbing against the base of the motor as can be seen by the attached pictures, this post is just a warning to be careful.

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Testing solid state relays

Today I pulled an ssr from a versalaser air compressor and wanted to test if it was working.

l started just as you would with an electro mechanical relay, l stuck a 9v battery across it and nothing. Then l remembered it was an ssr so l wouldn’t hear anything and I put my meter across the load terminals in continuity mode and got nothing.

Hmmm a quick google reveals all solid state relays need a powered load as they use some of that power to operate and a multimeter doesn’t provide enough.

So hooking a desk fan to the load side of things with the live wire connected to the terminals and a 9v battery to switch the relay results in the fan turning on, result working ssr.