Rotenbach Super 200p

[woody068]

Hello all, new to this forum.
I have a Rotenbach brand Super 200p and have been very happy with it until now.
I was going to do some MMA welding and discovered that i had no arc!
I double checked all cables, ground but they were good.
Then i tried plasma and TIG ,both AC and DC, same result, no spark at all.
The display reads "000" no matter how i turn the "amp knob".
The "over current light" does Not come on
I hear relays click as i switch from MMA to TIG, sounds normal
I have measured all power transistors and diodes and i cannot find any shorted component.
On the "top left" circuit board i measure 320 volt DC in from the rectifiers below but there is 0 volt out from this board.
I beleive the "front board" (the one with the potentionmeters) send controll voltages to the "top left" board to regulate current and so on but i cannot find any regulated voltage when i turn the "amp knob" and measure with a multimeter
There are 2 green LED's on the "top left" power board, they are lit up, (i think they indicate the 320 volt DC)
There are 3 red LED's on this board (and an small adjacent board thats soldered to this top board) none of these LED's are lit up.
there is a board "in the center at the bottom of the machine" this board gets 4 volatages from the transformer also down at the bottom.
the transformer puts out 4 20 volts in 8 cables that feed this board, there are 3 15volt voltage stabilisers on this board, they all have 15 volt out, but there are 4 connectors leaving this board, 2 wires each (red and black) leeding up to the different power transistor boards, there is only 4.5 volts at these connectors.
I am a trained electronics repairman (or used to be, i dont work with it anymore) so i should be able to repair this if i only had a schematic or got some tips on what to check next.
I will ofcourse pay for a schematic if anyone has it.
So anyone who had this problem or Everlast support, please post some info about it
Regards /Janne Strom

[DaveO]

Welcome to the forums!

Another member, Jakeru, had a similar problem and describes it in detail here. It involves replacing diodes, so with your electrical background this may be right up your street.

http://www.everlastgenerators.com/fo...ighlight=super

Good luck with it!

[jakeru]

I have measured all power transistors and diodes and i cannot find any shorted component.

Hi Janne - if you didn't find any shorts in your diodes, then for better or worse, you have a different problem than what happened with my machine (a 2007 Everlast Super200P.) Also comparing pictures of my machine to your Rotenbach, it appears there are some substantial differences. For example, your "upper left" circuit board for is larger than mine (with a lot more going on with it - See attached picture for a top view of my machine, FYI.)


Question: in TIG or plasma mode, when you trigger the arc, is the gas solenoid working?

FWIW, there is also a yahoo group "Chinese_TIG_welders" for these welding machines, although last I looked I didn't notice any schematics or detailed circuit-level info:
http://groups.yahoo.com/group/Chinese_TIG_Welders/

I know you already found WeldingWeb, which does have a few others who might be helpful. (And as you may have noticed, probably many more others making their best effort to be unhelpful )

Please keep us posted if you make any progress getting your machine straightened out, and let me know if there is something else I can do on my end to assist. Best of luck!

[woody068]

Thanks for your input Jakeru and DaveO, all input appreciated.
Ill check that "Chineese welder forum"

I think i have a controller problem, will try to find the time to troubleshoot it soon, will ofcource post my progress,if any , here.
I have looked at the river-weld.com and found replacement pcb's but theyseem to be a bit different than mine, i think they would fit your machine Jakeru.
Looks like a separate controller pcb and a smaller Power pcb like the one you have.
Regard /Janne Strom

[everlastsupport]

The Green leds would only help with the diagnostic procedure from probably the Cherry (sp) factory.

Jake I think had some bad MOSFETs and upgraded them when he changed them if I recall. Not a bad idea if this turned out to be the case.. Also, shorted is only one bad state, OPEN is bad too (no power).

I would signup for the Yahoo Chinese welding forum (Henry runs it, we helped over there as well everlast2009), but look for a schematic close to yours. I will see what I have from the OLD OLD days when we sold a similar unit, but we move way past those boards years ago.

If you find a close schematic you can take to a local repair person too.

[performance]

I have some info I can send you if you will email me. Can you find a company name stamped on the circuits somewhere?

[woody068]

I have some info I can send you if you will email me. Can you find a company name stamped on the circuits somewhere?

Thank you very much.
i have sent you an email
Regards /Janne Strom

[DaveO]

I have measured all power transistors and diodes and i cannot find any shorted component.

Missed that detail- sorry for stirring things up.