THCAD Environmental Fluctuations

Hi Guys,

I had a strange issue with my THCAD the other day. I have been able to replicate the issue under a certain condition,

So I was doing some cutting the other day and noticed the machine making some strange sounds. I went and stopped the machine and noticed that the torch had been going up and down. This is the result.



I looked at the display and noticed that the THC voltage was fluctuating wildly when idle. I think what caused the issue was the temperature in the shop was just under 40 degrees celsius. The next day I cut some more plates and it worked fine until the temperature got up to the 38 degree mark.

Any idea on what I could do to keep the machine working in those temps? Maybe more fans or some kind of cooler in the control cabinet?

Lol no I hate the cold! The thing is its not even summer here yet. Next Sunday is suppose to be 43 degrees.

I am thinking something must be wrong with the air flow in my cabinet. What would cause the fluctuations? The power supply to the THCAD? or some kind of emi?

Interesting artwork!

The THCAD is rated to 70 deg C so where is it located? In your control box? How well cooled is that?
Can you check the voltage with a multimeter at the THCAD input if it happens again.
I would be checking for noise in your electrical seeing you have made changes there.
You do have a filter on the power inlet to your box don't you? If not, fit one straight away.

Thanks Rod,

I will look into the input power filter, at the moment the incoming power feeds the UPS and all of the electrical items are powered from that.

Ill see if I can replicate it again in the next couple of days and do some more testing.

Rod, What do you think of this filter, www.jaycar.com.au/240v-ac-emi-filter/p/MS4001.

thefabricator03 wrote:

Rod, What do you think of this filter, www.jaycar.com.au/240v-ac-emi-filter/p/MS4001.

I think that would work if you had a hard wired power input. If you have used an IEC connector on your control box, this is much easier
www.jaycar.com.au/iec-emi-power-line-filter-6-amp/p/MS4003

Also add it to your control box to protect it from anything emmanating from the UPS.

The THCAD should work fine at 70C and even higher
Are you sure there is not an issue with connections?

A hot air gun or some freeze mist my help to localize the problem

Not sure about the connections. I have not touched anything inside the control cabinet or on the plasma unit. Its working fine at the moment, Ill see if I can replicate the issue.