Synchrowave 300- No Output- Hi Freq Only??

[slufkin]

Hi all, I am new to the forum. From Upstate NY.
I just got a Synchrowave 300 (freeby) for my son who wants to learn how to TIG weld. He is 17 and very interested in Machining and welding/fabricating (somewhat rare nowadays). I am a Machinist/Engineer and know very little about welding.
Don't have the serial number with me today, but I know I downloaded the book for serial numbers after JG064819, so its after that but before the next book... Sorry for that lack of info.
Heres where I am at:
Set it up for 230V input
Replaced the missing High Frequency rheostat
Repaired the broken wires on the foot pedal
Cleaned contactors and adjusted air gaps to .008"

Fired it up last night:
starts up fine-Fan runs, light comes on, has 115V power at the outlet
Foot pedal will initiate a very small arc IF you have the HF set to Constant.
Otherwise it will open the gas solenoid, but no arc whatsoever

Seems like I have high frequency only. Any ideas what would keep it from switching to a normal output amperage?

Don't be afraid to mention the obvious- as I said, I am not a welder and may well be missing something obvious.

Thank You for your time, I appreciate its value.

[raferguson]

Have you tried stick welding with it yet?

Have you checked that the cables are good? If there is a lack of continuity you might get HF but not welding current.

Have you tried more than one polarity? (In case the main switch is flaky).

[slufkin]

I do not have a stinger for stick welding. I never got the knack for it and sold off my old Buzzbox years ago. I could borrow one and give it a try though.
I will try to polarity switch, although I am pretty sure we tried it both ways last night.
Check cables with an ohm meter?
I'm sure the ground wire is good, but not positive about the torch conductor. I will check into it tonight.

Thanks for the help.

[cruizer]

Yep, see if it stick welds, as that tells us lots of stuff. Or with the HF off, and you have a volt meter handy, see what the output is at the output terminals. Generally with this machine. I find that Preflow is on wayyyyy too long, thus no output.

[slufkin]

Is there an adjustment for pre-flow?

[cruizer]

Apparently its an option, if its there, it'll be to the left of the on/off switch.
Does gas flow when you hit the pedal, and does it shut off when you release the pedal?

[slufkin]

I don't have gas hooked up, but I can hear the solenoid snap open when you step on the pedal and close when you let off.
I played with the post flow and that seems to work correctly.

I do not have the pre flow option.

[cruizer]

ok, then your going to have to either meter the output studs, or stick weld with it.

[slufkin]

I metered the output studs with the HF Turned off, and show zero volts output.
I tried it on ac&dc, str&rev polarity, and high&low range.
Tried it with current control switched to panel as well as remote.
I can hear the gas solenoid open & close and I can hear & feel one of the contactors open & close.
The contactor is not controlling gas as it closed as soon as you let off the pedal and the gas solenoid closes after the post flow timer times out.
That's about all I can tell you right now.
Any clues on where to look next?
I have cleaned & gapped the HF to .008".

[cruizer]

Tough one, PC1 is not turning on the scrs to fire, likely PC1 is the culprit.

[slufkin]

Tough one, PC1 is not turning on the scrs to fire, likely PC1 is the culprit.

Any way I can test it separately?
how do I identify it?

[slufkin]

Fixed....maybe.

I pulled the PC board out and cleaned the terminals. Cleaned all the connections to the relay that was firing when I hit the pedal, and low & behold, it seems to work.
I have to get chiller and gas hooked up then I will test it more.

Thanks for the help.

[cruizer]

Well, thats good news, now get yourself some preferably "MG chemicals" silicone grease, (dielectric grease) and stuff some into all those molex connections on the board, to prevent the corrosion from happening again.

[slufkin]

Good idea. Thanks.
This machine and three twin sisters sat outside under tarps for a few years..... No wonder it was nasty.
Anyone in the Upstate NY area looking for one, I can get you in contact with the guy who rescued these from the scrap yard. He probably wont give them all away, but pretty close.
I'll keep you all posted on my progress.

[slufkin]

Seems to work now

Got the chiller and Argon hooked up and after a little tinkering, it seems to be working. Now I just need to learn how to TIG weld...... Shouldn't take more than a night right?.?.?

I am not 100% sure the High Frequency is working, I have not tried to weld aluminum yet, just steel, but I did have the Hi Freq start on and it seems like I still need to scratch start it or at least come very close to scratching to start the arc.

How can I (someone who knows very little) confirm that the Hi Freq is working?