Rods "Spaceship" Scratch built Plasma Cutter build

BTW, plenty of SSR for AC can be found on old photocopiers, usually 2 in the same package ranging from 5 to 15A, all controlled by 5V ( tested and they all do work with 3.3V form the parallel port ).
DC ones are much harder to find.

No eBay APP ID and/or Cert ID defined in Kunena configurationThese look useful:

But it is worth noting that they switch to a common negative terminal, so your wiring needs to be suitable.
There is also an AC version of the same thing.

andypugh wrote: These look useful:

Thanks Andy. They do look handy. I am also looking for a couple of relays to be used as dry contacts on my Arduino Rotary table controller. I need one input (say 5-36V but 10-36 would do) and one output. Small would be good though!

@Rodw,

Maybe look at solid state relais, i see the previous post of Andy is also solid state, so good solution. They are 5v input and output is solid state. No mechanical clicking, just transistor technique.

I use them also with Ethercat for plasma start and to suit the plasma power by a combination of 2 fast solid state relais, connected in a c coded component to control digital plasma inverters that are non compatible with outside pc world. Like the new thermal dynamic 40-60i series with a Cat5 cable to the inverter. Modbuss is not fast.

I use in all plasma machine a 4 channel solid state relais : www.beckhoff.com/EL2794/
But you can order a standard solid state relais on ali too i think or maybe your interface provider has a solid state expansion set available.

How is your 120 amp's inverter doing the job? Did you cut 20mm already?

Grotius, thanks. I have upgraded to solid state relays on most circuits now as shown in the picture a few posts up. I've got a couple more mechanical ones to replace but have the parts here to do them. The hard thing is always to find something that is available and in stock in Australia.

The A120 inverter is working very nicely now I have ohmic sensing and clean dry air! The plasmac config is also working very well and has improved cut quality because of better height control. Actually, I am pretty amazed at the accuracy of the machine, M5 clearance holes in 2mm steel come out pretty much perfect!

I think its time to finish building my machine! I have a few little things to do in the control box and finish off the table.

Rodw,

All info sounds very promising !!

A tiny problem your realised yourself, the current stock in Australia, to anticipate this in your current business model will
make you rich !
A good strike evolves most of time out of a problem.

" if there’s any way they can do it wrong, they will ". But inversing the law of Murphy will bring you luck !!