TEC Arc Foot Pedal Amperage control Inverted

[akaolliebailey]

Hi there, new to the forum! I'm running a Thermal Arc 202 AC/DC tig welder and recently bought a TEC Arc foot pedal to use with it - the proprietary foot pedal from thermal arc was out of budget. The issue I'm having is that the amperage control is inversed, meaning I have max amps at the top and low amps when the pedal is fully pressed, which results in sometimes getting a huge spike when I back off and the arc burning a huge blob into the end of my weld. Obviously getting the OG pedal is the best solution, but I was wondering if anyone had experienced something similar with after market pedals and if there was an obvious fix. I have tried switching the max/min wires inside the pedal but this results in not being able to control the amps on the machine. Any advice would be greatly appreciated.

 

[500e]

If it is a pot swapping the 2 outer wires should reverse the pedal operation

 

[Munkul]

what he said. Tec arc support should be able to advise, but in this case I think I'd just be checking it with a multimeter, reversing wires, checking again, if all good then job jobbed.

 

[tom2207]

or swap the two pins in the connector , may be easier ,,, Jim was the pedal man from memory.

 

[hotponyshoes]

One of the 2 outer pot wires has a resistor connected. Might be at the plug end?

As above, you'll need to swap the 2 outer wires over to get the direction working correctly but the resistor will need to stay in its original position to activate the amps selection.

 

[akaolliebailey]

Thanks for all your help! I took the bottom off the foot pedal and switched the wires over from pin 5 and 6 (its an 8 pin plug) that control the maximum and minimum on the potentiometer - its fixed the issue but now means I cant change the max amps on the machine unless the pedal is un-plugged, I called Tec Arc and they said this was the typical outcome for Thermal Arc machines, this also seems like a common issue, and might be because the machines were wired wrong from factory as they've checked their end and its all correct.

side note, as I was spending some time fixing it I added a foot hook so I can move it around easier, all in all a good mornings work.

 

[Erie Fred]

First time a drove a dozer with a de-acceleration pedal was "fun".....to say the least.
Once I got used to it, it is great.

 

[hotponyshoes]

Thanks for all your help! I took the bottom off the foot pedal and switched the wires over from pin 5 and 6 (its an 8 pin plug) that control the maximum and minimum on the potentiometer - its fixed the issue but now means I cant change the max amps on the machine unless the pedal is un-plugged, I called Tec Arc and they said this was the typical outcome for Thermal Arc machines, this also seems like a common issue, and might be because the machines were wired wrong from factory as they've checked their end and its all correct.

side note, as I was spending some time fixing it I added a foot hook so I can move it around easier, all in all a good mornings work.

Pin 6 has a resistor (might be a solid link) that goes somewhere. (Pin 8 maybe)
If you have swapped 5 & 6 you'll need to put the resistor back onto pin 6 to get the max amps control working again.
I think pin 5 is the live side so hopefully it's not damaged anything connecting the resistor/link to that.

If you have a multi meter (or even just a volt meter) it is easy enough to check if it's the machine or the pedal that's wired wrong.
My money would be on the pedal as I'd expect the thermal arc loom to be machine made?

 

[carbon]

but now means I cant change the max amps on the machine unless the pedal is un-plugged

If it’s anything like my thermal arc 250 you can still adjust the current but you have no indication of what you changed it to as the display shows the minimum current set with the pedal at rest. I fitted a switch to my diy pedal that disconnects the pot from the cable /plug and then the welder displays the max weld current. Obviously needs re connecting for the pedal to control the weld current but saves wear on the socket to the welder

 

[hotponyshoes]

I don't think the 202 is much like the 250.
I think the 250 has a 5 pin plug?

The 202 has 2 remote control options.
Foot pedal and a hand-held thing.
The hand-held is an arc/mma remote.

It needs the resistor/link wired correctly to tell the machine you are using the foot pedal.
If the link is not connected the foot control should just act like the hand remote (ie only work properly in mma)
I'm not sure what happens if the link is connected incorrectly, probably what is happening to the OP.

Might also be worth looking in the user/service manual.
If I remember correctly there are some dip switches inside the machine. One of those is something to do with foot pedal behaviour.

Again, from memory, but if the machine is in max amps limit mode you might have to do something like depress the foot pedal fully and hold it down while setting the max amps on the machine.

 

[Mark 2]

Turn it round

 

[Erie Fred]

Turn it round

Attach it to the ceiling.....

 

[Mark 2]

Attach it to the ceiling.....

Well the lack of replies would suggest to me, Fred, that people are trying out our ingenious solutions. I expect praise will be forthcoming.

 

[addjunkie]

The Thermal Arc pedals are actually made by SSC. Think this is the right one

https://ssccontrols.com/uploads/Product-Information-Sheet-C850-0825-TIG-Foot-Controls.pdf

 

[akaolliebailey]

The Thermal Arc pedals are actually made by SSC. Think this is the right one

https://ssccontrols.com/uploads/Product-Information-Sheet-C850-0825-TIG-Foot-Controls.pdf

Thats good to know!