Welding Tips and Tricks

Hi all looking for a foot pedal for my Cemont I see some of you have made a pedal for your machines but couldn’t find wiring diagrams or pot size etc bit of an electronics novice so any help appreciated didn’t want to toast my welder

I think a 10K pot is pretty standard, but honestly you won't damage anything if you are slightly off on the sizing. As for wiring, there are usually 5 wires 2 for the contactor micro switch, and 3 for the variable resister. 1 for each end of the resister and 1 for the wiper. Now which of the 5 wires goes where in your machine I couldn't say. Maybe someone else has that answer.

The Cemont Smarty tx160 AC/DC was sold under several names like the Air Liquide T 150i AC/DC, Oerlikon CITIG 1500 AC/DC (internal circuit boards are the same, although here they dropped the external pedal connector for some reason), SAF-FRO SAXOTIG 160 AC/DC, etc.

Like Louie said, there's not much in there. It's basically a switch that turns the arc on/off and usually a 10k pot that does the amps adjustment by working as a voltage divider.

On these machines you also have to short 2 pins in the connector to let it know the pedal is connected. It will then disconnect the front panel controls for amp settings and such. (postflow and such remain operational)

On these (quite basic) machines this means the pedal works fine, but normally it always operates on the 0-150A range from 0 to max and you can't adjust that on the machine itself directly.

If you want your full pedal travel to (for instance) go from 0-50A on the machine then the usual trick is to put a second pot in series to provide the offset/limit.

Sometimes you see it as a second pot on the pedal on some machines, other people install them as a second one in the case itself like was done here:

https://www.youtube.com/watch?v=_KInGWLBwcE

I did find the attached pinout for a Cemont welder and it has all the required connections, but I don't know for what model/type though, so not sure if the pins are exactly right for the Smarty tx160 .

Hopefully it gives you some info..

Bye, Arno.

Thanks for the replies it helps a lot I have got manual I’ll dig it out and post the wiring diagram it has a ten pin connector

This is the wiring diagram from the manual e and f torch trigger abc pot I guess not sure about h if that makes any sense.

Yup..

Should probably be: A - B - C -> 10K pot

You need to use a multimeter to find out which pin provides a (low) voltage, which is ground and then the remaining one would be the wiper connection.

E - F -> trigger switch

LIkely you'll need to link 'H' to the power pin in the A-B-C range so the welder knows that the pedal is connected and overrides/shuts off the front amps adjustment.

Bye, Arno.

Thanks for the help just need to find out which one to connect h to then I should be good to go I’ll get my multimeter out and see what’s on whate

Hi all got a bit of time so going to look at the pin outs on the welder to try and figured out how to wire the pedal being a total novice will I need to open it up and use the earth on the control board to get the readings with a multimeter or can I just use one of the case screws.
I have emailed Cemont to see if they will give me the pinouts for the pedal but I’m not that hopeful.

If you open up the machine you should at least already be able to see with the schematics you have which pins on the circuit board go to which pins on the connector.

If I recall correctly they are in a single row connector on the circuit board like on the diagram, so you should be able to see the 'X7' connector and trace the wires for the torch trigger (1+2), 10K pot (3+4+5), pedal-present (7) to the specific pins on the outside connector.

If you're not in a hurry I can see if I can open up my machine (Mine is an Oerlikon, but should be same internally) and get you the connection diagram in a few days.

Bye, Arno.

Thanks that would be great I’ll get it opened up and see if I can see what’s needed I’ll take some pics thanks for the help

Hi I’ve found a repair manual for a Cemont tx 150 with the same board part numbers as my board I think looking at the wiring diagram it shows switch pin 1 and 2 power for pot pin 5 wiper pin 4 and earth pin 3
Not sure about 6 and 7 as mine only shows pin 7 nothing on pin 6 I took the cover off but I’m none the wiser as I’m not good with electronics if anyone needs the repair manual let me know.

Yup..

Looks like your machine is pretty much the same as mine internally. I just added the wiring for the pedal as mine is a model where they did not bring the wires to the front:
The wiring to the 7-pin row should indeed be:

1 + 2 -> trigger switch of the pedal

3 = potentiometer +
4 = potentiometer wiper
5 = potentiometer -/ground

6 = not connected/not used

7 = connect/loop to 3 to indicate 'pedal present'.

Aka. pin 7 you just put a loop cable in the connector coming from the pedal so that pin 3 and 7 are linked when the pedal is connected to the machine. This overrides the front panel amps settings and allows the pedal potmeter to adjust the amp settings on the fly.

The pedal should be set up (a bit odd, but hey) so that at rest the wiper has '0' resistance to pin 3 and should move to pin 5 as you press the pedal more.

3/4/5 (and 7) are all based on quite low voltage (around 0.6V), but the trigger switch connection is something like 22V, so make sure not to connect those together or likely the magic smoke will come out..

Bye, Arno.

Thank you so much for your help I will connect it up and see what hapoey

Long time I know but finally got round to wiring up my foot pedal and all is working fine big thank you for all your help and advice

Great!

These are not special machines, but are decent for what they are and useful as low end AC and DC units.

One thing you can do as a mod or upgrade is to add a second potentiometer in series with the pedal. That way you can adjust the upper limit of the weld current when the pedal is 'full throttle'. Some pedals out there even have this as a feature where there's an adjuster/knob on the pedal itself.

By default the pedal just replaces the front amp control when you plug in the pedal and it always has 0-100% current range when the pedal is in use. By adding another potentiometer in series you can effectively set a lower max amps to for instance full pedal is 25A.

You will need to use an amp-clamp meter to determine the relation on the adjuster to actual max amps though.

Bye, Arno.

Hi Arno pedal I had already had a second pot on it and it seems to work great just welding some really thin mudguards at the moment and it really helps I only use it for restoring my old motorcycles and it seems quite a nice machine for this I’ve got an old 300amp castotig but the hf start has packed up so I find it hard work on really thin stuff probably just my skill level also find the pulse on the tx160 helps a bit as well