So you want an ON BOARD WELDER. You've broke on a trail and need some welding work done to get home or maybe just to get off the trail. You were either unlucky and had to spend time waiting for help, or you were lucky and ran into somebody that had an on board welder of their own and fixed you up and now you see the light and just can't do without one for yourself. Maybe you have some equipment that needs repair from time to time and it's easier and cheaper to be able to weld it yourself on the spot instead of hauling it to town rather than paying somebody else to come out and weld it for you. Either way HEHR POWER SYSTEMS has the answer. It's called the POWER ARC II. This is a top of the line on board welding system and DC power source that is sure to leave you with a smile the first time you use it. This welder uses a high output alternator (They make their own, or you can use your factory one if it has a high enough output) and a Control Box to produce a high frequency DC arc that can weld up to 1/2 inch thick steel at a 100% duty cycle. You can also Mig and Tig weld with the unit (with the proper attachments). It also produces 120 volt DC power which you can use to run any type DC tool, or AC electric tool that has a brush type motor. The unit is also a very powerful Battery Quick-Charger/Booster. You can quick charge or boost off any 12 or 24 volt battery. For those of you in construction this means that you can charge or boost off those giant pieces of earth moving equipment without any special carts or other equipment.

This is the Control Box, you can see all the units switch and control knobs as well as the wires to hook it up.

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This is the Hehr Power Systems Alternator, this model is 195 amps, it came with the bracket and pulley.

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The heart of the unit is the Control Box, which uses a state-of-the-art Motorola microprocessor to control all modes of the Power Arc II's operation. The Control Box face has all of the unit's functions laid out on it for quick reference (in case you don't have the very comprehensive instruction manual on hand). In the center is a large, round LED display that shows power output (both the direct and the welding depending on which mode you're in). It also has 6 small LED indicators to show what mode the unit is in and for diagnostic functions. The control switches are on the left side of the power output window and directly below the window is a power adjustment knob for the welding current. To the left and right of the power adjustment knob are the receptacles for the positive and negative stinger cable plugs. The 120 volt DC power outlet is on the upper right of the unit above two fuses. The Control Box plugs into the Alternator Wiring harness with two large color-coded and indexed plugs so that you can't incorrectly attach them and so that no wire cutting is involved.

Here is a close up of the Control Box, you can see all the L.E.D.'s and read the descriptions of each control.

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This is the Control Box plug end of the wiring harness. They plugs are indexed so that you can't hook them up wrong.

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One other neat feature the unit has is an Automatic Recharge Cycle. Because of this feature, you can't discharge the battery too much so that you would not be able to crank the vehicle should the engine die for some reason. Before the battery is discharged below its cranking capability, the Power Arc II interrupts its welding/charge, or tool mode to re-charge the vehicle battery for approximately 10 minutes (longer if necessary). After it completes this re-charge cycle, the Power Arc II is ready to resume the mode of use it was in. Depending on what vehicle you are going to install the unit on, all you have to do is throw a switch and the r.p.m. is automatically controlled. This would be the case if you own a newer vehicle with a computer controlled throttle that allows you to wire the Control Box into. However, if you have an older vehicle a Vernier Throttle will have to be used to adjust your engine r.p.m. for the desired power level. Hehr Power Systems can determine which way you need to control your engine. On the old 1977 model I have, the Vernier throttle is what is called for. The system also comes with a complete wiring harness in your choice of lengths. All ends are pre-terminated with connectors or plugs and is contained in a plastic sheath to make for a nice, clean and almost fool proof installation. If you have any problems understanding the very comprehensive instruction/installation booklet that comes with the unit, give their tech support a toll free call and they will be happy to walk you through the problem. I had a few questions and issues that they answered and got me straightened out in no time.

Vernier Throttle Control Cable, with mounting bracket and installation hardware.

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Wiring Harness with pre-terminated ends and in its blue plastic protective wrapping.

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On to the installation... The first decision that you have to make is where you want to mount the Control Box. Hehr Power recommends at least twelve inches from your battery. On my vehicle, I had to leave it on the passenger side fender well and only had room for ten inches from the battery. The twelve inches is a safety precaution. I drape a piece of canvas over my battery which really "covers" this concern. Once you pick a spot, you need to "test route" the wires and the Vernier throttle to make sure they will work where you want them and that they are long enough. After that, if you can't bolt the Control Box down directly, you have to make mounts for the Control Box to mount to and then attach the Vernier throttle mounting bracket to a suitable location. I made two holes in my inner fender and then made a small mounting bracket that I welded to the inner fender for the other end. I also attached my starter solenoid to this bracket.

Here is where I mounted my control box on the passenger side fender well, on the left you can see the bracket I made. Click Image for full size photo	The black wire under the radiator hose is the Vernier throttle cable. This is where I mounted it to attach to the carburetor. Click Image for full size photo
Vernier throttle cable attached to the carburetor. The chain give it enough slack so as not to interfere with any of the other linkage. Click Image for full size photo	The control box is mounted and ready. The knob end of the Vernier throttle cable is mounted on the right side of the mount that I made for the control box. Click Image for full size photo

As soon as you have the Control Box and the Vernier throttle cable mounted, you have finished the hard work. The next step is to remove all the wires from your stock alternator and move them to the side for now. On my 1977 model, I had to use one wire from the stock plug to hook to one of the harness wires. The rest of them were coiled up and wrapped with electrical tape and zip tied out of the way. Now all you need to do is replace your stock alternator with the Hehr Power unit (unless of course your alternator is large enough and you are keeping it) and then hook up the harness. The Hehr unit, along with my system is rated at 195 amps. This will let me weld anything and everything that I could possibly want to, all the way up to 1/2" thick steel plate. The unit is massive in construction and built very heavy duty throughout. The bearings are a lot larger than a standard alternator and the one in the rear protrudes out the back about an inch or so. It has two large studs that protrude. The plugs make it a breeze to wire and you only have a hand full of wires that you need to connect to the battery and to a switched 12 volt power supply that is not on while the ignition switch is in the start position and you are done! There is even a wire for the auxiliary battery (if you have one). To use this feature you MUST have an isolator wired into your duel battery setup!

Left is my 120 amp CS series alternator, on the right is the 195 amp Hehr unit. Click Image for full size photo	This is one of the large bearings in the Hehr unit, it is protruding out the back. Click Image for full size photo
Stock alternator bracket that held my 120 amp model. Click Image for full size photo	This is the Hehr unit with its beefier alternator mount. Click Image for full size photo
These are the wires that attach to the alternator from the harness. Click Image for a full size photo	Here are the wires that will connect to the battery and power wires. Click Image for full size photo

Once it's all wired up, take your time and re-check all the connections to be sure that they are exactly as the instruction manual indicates. It's much easier to recheck and find a problem, than to be in a hurry and have something connected wrong and burn up a component!

Wired up, double checked and ready to go.

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This is the completed unit. Control Box, Alternator, and Vernier throttle.

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Now that everything is installed, hooked up, and double checked to ensure that all the connections are correct, let's see how it welds.

Here are the welding stingers that came with the unit, 4 gauge and 20 ft long. Very high quality stuff. All ends were pre terminated and they were ready to weld. Click Image for full size photo	Getting ready to weld. Whoops! He's a bit small to be doing that... No, I did not stage it, he did it on his own... (Yeah Right) It's not really connected, but he did not know that. Click Image for full size photo
A nice controlled arc, not near as big or as sloppy as an A/C welder. Click Image for full size photo	Clean, tight and good penetration on the weld with a 1/8" rod in 1/4" metal. Click Image for full size photo

I only have one thing to say after welding with this system. WOW! Never have I had such clean and precise welds with an arc welder. The high frequency D/C arc took a couple of seconds to get used to, the whine it made threw me off and I stopped welding for a minute. I thought I was burning something up. I re-read the instruction manual and felt a bit silly when I read that the WHINE is normal! Hats off to the folks at Hehr Power. They have built one fine piece of equipment that should serve me well for quite a long while. I can't wait to try it out... On somebody else's rig that is... See ya on the trails! Any questions or comments please feel free to e-mail me. depdog@off-road.com Glenn

Hehr Power Systems 1800 443 9394

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