Lincoln K870 Amptrol Pedal vs K813 Pedal

[jackd942]

I have an older machine that I acquired in which I can't find a manual for. It's a Lincoln Tig 300/300 made in 1984, but the code # doesn't match anything on Lincoln's site. Anyway, I found the manual for that particular model with the same date on it, and it appears to be correct. The manual states that it requires a K813 Foot Amptrol. I can't find one around anywhere, but did come across a deal on a K870 Foot Amptrol which has the same plug on it. Also can't seem to find a pin-out on the two models so I'm not sure... Just wondering if the K870 would work for this machine even tho the manual called for the K813? Still waiting for some other torch parts and such to come in and thought I'd ask in case anyone out there knows anything about it.

[rode2rouen]

When all else fails, call Lincoln HQ. 216-481-8100

They have engineers with the info you need (pinouts and such), and in my experience, are always willing to help.



Rex

[hillbillyfab]

Glad to see this brought up. I've got a TIG 300 aswell. Code 6187-H, alittle bit older. I've got the foot pedal and the torch mounted switch. What I'd like is a torch mounted remote to increase/decrease amps.

[ccawgc]

As long as the tig 300/300 has a electronic control pcb. any foot control with a single round connector should work. If you have a tall round top tig 300/300 and the remote uses two separate plugs.A three pin and a two pin. This model uses a very high wattage rheostat in its remote and the current from this model will burnt up the newer remotes.
code 8875 seems to be the point where changes were made.
All the different remotes are listed in parts book 66

[hillbillyfab]

Yea I've got the two plug model, 3 & 2 prong style plugs.

[ccawgc]

That being the case you will melt any remote control you attach unless the rheostat can handle 6 to 10 amps. The full reactor control current goes through the remote.
You can try contacting profax/lenco and see if they have a hand control that will work with your older welder.
The only other way is to come up with a electronic control module that can be controlled by a standard hand control. Either a DC voltage control put right in the control circuit.
Or a complete redesign using a AC light dimmer placed before the DC rectifier in the reactor control. Some sold state relays can be used as dimmers with just a potentiometer for control. You will have to experiment until you find a system that works for you.
I once tried using a DC voltage regulator on one, with fair results. If I had to do it again I would put my control in the AC part of the circuit. High power AC controls are easier to get.
If you need a clean diagram call Lincoln with your code number and ask for one to be e-mailed to you.

[jackd942]

Thanks for the info ccawgc...My code doesn't match anything on their site (SPL-B443-84), but in looking through the different manuals, Code 8888 seems to be the only one that matches up (with photos and controls exactly as they are in the manual). It does have 1 single 6 pin connector and is not the tall round top machine. Thanks again.

[billbigrig]

Howdy,
The K870 Amptrol pedal will have the switch contacts on pin D & E. Looking at the plug, with the slot on top, they are the 2 pins to the left of the top one. The variable pins are; A to B, high resistance to low resistence. Pin B is the wiper of the potentiometer. C to B is the low resistance to high resistance. I have 2 of these, one unused, one very lightly used. I also have a dozen or 2 that some can be easily repaired, others, a little more involved. Last time I had to replace a potentiometer assembly, Lincoln's cost $72. I could probably second source the pots through Digi-key or Mouser for about $8- $10. Seeing as we have switched over to Miller Dynasty models exclusively, These are headed for who knows where. The more severely damged ones I might make into cool looking stompboxes for music effects pedals. They would survive the rigors of concert touring much better than most of what's out there.
Rig

[billbigrig]

Well, the 2 prong connector is most likely the wires to the gas on solenoid. That would be your pedal's microswitch connection. The 3 wires will be the variable power. If things are lucky, the "center" pin/hole will be the wiper. Then all you need to figure out is the high/low resistance sides. The K870 uses a 10K, 5 watt potentiometer, with a pair of 4.7 nf, 3000 volt capacitors. One each between the center terminal and each outer te
Rigrminal.

[papaharley03]

These guys make the pedals for Lincoln. Might give them a call and see what they can do for you.

http://www.ssccontrols.com/index.htm

Note: They do not make pedals for the older machines that use high power resistors in the pedal.

[jackd942]

Thanks for the info ccawgc and everybody else. ccawgc, by our pm's, I was able to pretty much test everything out ahead of time and had a pretty good idea that everything was in working order. The rest of my parts came in today and after getting everything together, it worked flawlessly. Now just need to practice and get in some seat time since I've never done any TIG welding before. Thanks again.

[billbigrig]

Just finished going through 2 boxes of these K870 pedals. I have a couple dozen that test good. The only trouble is the connecting cable. Trying to get a part# and price for the cable, but might let them go as-is for folks who can replace the cable themselves. seeing as the cable has a pre-wired plug on both ends, it shouldn't be a big deal. Also some Hobart 09004A pedals. Same deal. Test good, but needs a cable.
Rig

[billbigrig]

I take that back. at $178.89 for the cable, I think I'll get out the solder and heat shrink tubong and repair the cables myself. The cable costs half of the entire pedal!!!
Rig

[papaharley03]

I take that back. at $178.89 for the cable, I think I'll get out the solder and heat shrink tubong and repair the cables myself. The cable costs half of the entire pedal!!!
Rig

Nothing special about that cable that you couldn't source it by the foot or by the reel. Belden makes good quality stuff. You sure don't want to buy it from Lincoln.

The link I posted above for the maker of those pedals might even have a decent price for cabling.

If I were close enough, I'd offer to fix a few of them for ya.

Papa