Miller 1E Welder/Generator voltage change

[Tom Reed]

I am in the process of rebuilding the Kohler engine on a Miller Roughneck 1E welder/generator. These were available with either 120 or 240 ac outputs @ 1800 rpm engine speed. The one I have is 120 vac and I'd like to know if anyone here knows if there are some taps somewhere on the machine where 240 vac could be had.

My goal is to set this up as a backup source for the Listeroid should it fail. The 3kw @ 1800 rpm is just about right as that is what the Listeroid puts out too. There is also a good pile of 3" x 21' water pipe that I plan to make a pole barn out of that will need a lot of tabs weld to it for bolting the wood roof joists too.

Also, any here have a gas tank and straps for a K301? The one that came with the welder is a bit rough.

[mobile_bob]

i absolutely love the miller 1E welder, one of the best little units ever made.

somewhere i have the schematic for the machine, but i have no idea where it is

you can contact miller and they will provide you with a schematic for your machine, you just need the s/n on the front control panel
so they can identify which version you have.

btw, i have one i bought in '83 it was built in '67, when i got it the thing would blow through a quart of oil in 15 minutes of weld time, killing every
mosquito withing miles in the process.

i lifted the head, and removed the crankcase bottom, tilted it up on the generator mounts, replaced the piston, rod and rings, new gskts and a cylinder scuff with emery paper and i has never used a drop of oil since! 

i love the thing because of its ability to produce 120vac at 1800rpm and weld at 3600rpm.

mine also is setup as a 120 only machine

i have  a 2E with the 16hp ohv tecumseh, it is set up as a 120volt machine, however it can be reconfigured for 240 internally

come to think about it i think you can find the schematic for your machine online at millers website.

bob g

[Thob]

Try Miller's web site:

http://www.millerwelds.com/om/o419f_mil.pdf


You might get a better match if you have the exact numbers for you machine.  I looked it up based on "Roughneck 1E".

[Tom Reed]

Ok so this is the schematic. The generator section seems to be a separate set of windings, so messing with it won't harm the welder portion. So it looks to me like the 120/240 selection is through a switch? Perhaps the same multi-pole switch as on the throttle?

[mobile_bob]

if i read the schematic right, it should be via the toggle switch in the control panel, not the throttle switch which in mine is just a microswitch
and not large enough to handle 3kwatts.

bob g

[mobile_bob]

while you are in the panel wiring, take a look for diode d-12
in mine it was very hard to find because it was soldered inline with the wire and slid inside a piece of woven loom

i had a hell of a time finding that problem on mine when it failed, because i didn't even know there was a diode feeding the sliprings
much less that anyone would hide in inside a wire loom!

it might be a good idea to find it and replace it while you are in there, iirc  i used a radio shack unit that would handle a couple amps
and all went back to normal.

bob g

[Tom Reed]

Ok, then if I understand the schematics correctly switch S1 on the front panel is what that is showing. As shown on the schematic has got the windings in series for 240vac and on my 120vac wiring has the windings in pairs of 2 in parallel, correct? The 120vac diagram is not shown.

So what will need to be changed if we can infer how it is wired now?

[mobile_bob]

as near as i can tell, it appears that the power coils in the stator are displaced by 180 degrees

so coil 1 and 3 are in series as is coil 2 and 4, then these two groups are placed in series via the power/weld switch on the front panel
the output of coil 1 and coil 4 look to be connected to the receptical on the front cover according to the schematic, with the third pin as ground
which would be expected.... so

if your machine is wired to this schematic, it does not appear you can reconnect anything to get 240vac at 60hz, it appears to be connected in series already to get the 120vac, and if you reconnected to parallel you would get 60vac at 60hz at 1800rpm.

have you confirmed this schematic as being correct for your machines s/n?

all said and done, you might have to find a transformer to step up the 120 to 240 if 240 is what you need.

bob g

[Tom Reed]

Are you sure Bob? I always thought (perhaps wrong) that on a 4 pole machine each pole put out 60 vac. 2 in series makes 120vac and 4 makes 240vac.

[Thob]

Time to get the voltmeter, open up the generator and measure leads 14, 15, 17, and 19 and see what you've really got.  Be careful, high voltages present!  Further down in the document (p21/pdf page 27) there's another diagram that shows a 120/240 setup with a switch.  Different models?  Different years?

[highwater]

Also, any here have a gas tank and straps for a K301? The one that came with the welder is a bit rough.

Hi Tom,

I see some tanks and straps on this forum quite often.
4th section down is the classifieds.

http://www.ihcubcadet.com/cgi-bin/discus/discus.pl

edit: on the for sale section at the top there are the archives.
Go to June 24 archive and down about half the page.
tank from a 10hp.
I don't see where he ever said it was sold, but you know how that goes.


Randall

[mobile_bob]

we really need to know which version of machine you have,
then we can determine if you can reconfigure to 240vac operation

see the thing is, there are two sets of windings on the stator, one for welding, and another for AC power
then there is the thing with it producing power at 1800rpm
there may not be enough room to get enough turns of wire in the slots available to get 60volts per pole at 1800rpm

from the diagram/schematic you provided there is no way to reconnect it as 240 at 1800 rpm, perhaps another model does
but i haven't looked at all the available schematics

however i will go back and take another look, hopefully i am wrong

bob g

[Tom Reed]

Bob, the S/N is HH103631

Randal, thanks for the link I contacted the seller. Lots of good small tractor equipment there too. I have a Bolens Husky 800 that gets used in the garden.

[mobile_bob]

looks like this is the correct manual and schematic for your specific machine
and it doesn't appear to me that it can be reconfigured for 240vac

at least not at 60hz and 1800rpm

http://www.millerwelds.com/om/o419e_mil.pdf

bob g

[Tom Reed]

Ok, different windings from the factory for 120 vs. 240 v would be a good reason why the schematics are the same for both versions. And darn it, I have a 2kw transformer, but it's not quite big enough to do the job.