Connecting pneumatic pressure switch to ULS laser

[Allan Longson]

So my air compressor died at the start of a long cutting job, the compressor didn't stop running, it just had 0 output pressure. I didn't pick up the problem until after the job had finished, 1 hour of no air pressure out of an air cone means 1 damn good, expensive lens ruined. This isn't the first time this has happened to me and I'm now determined it will be the last. I'm going to add a pneumatic pressure switch into the laser circuit, I don't think putting it into the 240v supply line is a good idea so was thinking of splicing it into one of the interlock switch lines, no air pressure therefore no laser beam.
Anyone else done this and maybe placed it elsewhere?

[Scott Marquez]

That sounds like a great idea, maybe you could contact ULS for their thoughts on this.
Installing it in series with the existing interlock circuit sounds like a good idea.
let us know the outcome.
Scott

[Scott Shepherd]

Just for reference, my PLS has the air system on it. You tell it that one color has air (and what percentage of air pressure it should flow at), if that starts and the air isn't there or it drops below a certain acceptable level, the machine stops and an error message comes on the screen and tells you that the air is too low to continue.

I only mention this because possibly the mechanics are there. Maybe you can find a pin out for the board and determine which pins get the signal to shut it down. Just something to think about.

[Allan Longson]

My VLS has the ability to select "Enable Air Pressure Detection" in the system settings. According to the local agent, if it is enabled the laser should not run if the air pressure gets beneath a certain level. However whilst the machine detects if the air pressure is on or off (this can be seen in the diagnostics window when you select the external device "Air"), it doesn't stop the job from running. I can turn the air off either at the start of the job or even half way thru and the machine just continues on as if nothing has happened. Sadly not what I want and not worth getting the motherboard repaired / changed if that is where the issue is hence the thought of going into the interlock line with a simple, low cost 5v external air pressure switch.

[Ray Scott]

I think a basic pressured detecting switch can be added to the safety interlock section of most any laser system. I work with the Chinese laser machines (mostly) ... I have put the air pressure detect, water flow detect, water pressure detect, main door closed, "air filtration ready", .. These safety devices can be wired in series with "dry contact" interface. The problem we run into is easily identifying to the user of which failure actually caused the laser machine to stop running.

Thank You,