SIP 130 wire-feed power supply - alternative approach

[cracker666]

The trim pot to replace is it the one which attached throught the welders front panel.
or the little trim pot located on the lower left of the pcb from inside?.
The links I have seen are mini pots, But
then I notice that on one mod the main Pot has been replaced and no not for the 10 turn one.

So Im confused I have a load of pots just need to bung one of then in, without going bang

 

[Sean]

i wouldnt bother unless the one on is faulty, your going to have to bite the bullet and start welding with it rather than dressing it up.

 

[cracker666]

The wire feed was a tad fast for 0.8mm on the close to zero setting so I believe that it needs to have another mod to scale down the speed

 

[Sean]

you did try setting the wire speed knob on the front to min then using the trim pot on the PCB to turn it right down to "creep mode"?

you cant see it in this photo but its a small one just under the blue to red crimp lucar

S

 

[cracker666]

M8 you are a star cheers,
Then im already.
Wire, Tips, Converter Hose, everything I needed has arrived and just needs putting together.
So out with the Gassless and in with the Gas.
Need a Trolley thing, maybe one of the first things to make.

 

[cracker666]

All ready to play

 

[cracker666]

I know 1K trimmer it should be changed to 100ohms but it work great now, so when Im bored Ill do it.

 

[cracker666]

I fitted the 2.2nf (2200pf) cap to the motor, got bored :-)

 

[jateu]

Late Entry

Hi All,

Just been looking around to see which mod would be best for my sip 130! I've seen the mod without PSU looks good, but it's this one using laptop PSU that has my attention ! I've been out and hooked up multimeter to see what volts get to motor they are as follows.

Min-Low Slow = 8.4v
Fast = 24.2v

Min-High Slow = 16.6v
Fast = 33.5v

Med-Low Slow = 10.4v
Fast = 26.1v

Med-High Slow = 20.4v
Fast = 37.1v

Max-Low Slow = 13.1v
Fast = 29.3v

Max-High Slow = 25.6v
Fast = 41.9v

So with the following above info what u would you recommend and how would you control the voltage from 8.4v to 41.9v

Many thanks

James

 

[cracker666]

My friend I measured it and decided to do the mod anyway, its fully reversable if your not happy with it.
Im welding from 1mm to 2mm and on power two ie low/medium and if you picture a clock wire speed is on 8 - 8.5 it sizzles great and full of control.
If you need any help pm me, I can take more pictures and even have a spare relay and psu.

 

[Mattycoops43]

Right, finally got hold of the bits for this today. I am 80% through but need a bit of advice. So far;

gas solenoid fitted (ac) and wired up using T connection on board, all working fine.
PSU powered up from mains switch, going on and off with power switch.
Relay mounted on the floor ready to connect up.

Basically I need a bit of clarification on wiring the relay. I am trying to follow the steps on page one of this thread, and I can follow it, but I need to check I am getting this right.

First, I am new to AC relays. The Gas solenoid uses 3 connections, this I understand, the relay only has 2 to switch it, am I right it is neg-live that energises it, or is it live to earth?

Second, the negative dc feed to the motor from the psu, it says to connect it to the current neg connection but doesn't that mean it is bridged across to the transformer neg? I thought the voltage to the motor would be isolated from the other circuits. In my head (usually wrong) the dc voltage at the relay should be the only thing going to the drive motor?

Other than that, I think I got it, can someone just clarify which connections in the original wiring need to be cut or isolated?

Thank you. So far, it has gone fine and everything worked first go, I don't want to mess it up now.

 

[rtbcomp]

Solenoid - live & neutral. The earth is a safety feature and should be connected to the chassis of the welder. It's worth mentioning that the welding "earth" (return) should NOT be connected to the case.

Looking at the circuit connecting the motor as described looks fine as long as you break the connection as shown in the diagram.

 

[Mattycoops43]

Right, I am needing a bit of help here. The issue is, I was all set to wire in the power supply, understood the theory and was following the instructions from page 1, the issue is, I don't think my welder is wired up the same way as the example.





I identified the white wire that goes from the welding transformer to CN5, it is joined with a pale blue wire which then goes into the torch and the trigger microswitch, it then returns as a dark blue wire and goes to CN1.

The wires to CN1 are

Black-goes to the big plate with two levers bolted to it (sorry, lack of terminology)

White-goes to motor +ve

red goes to welding transformer, and appears to go to the same place as the white wire from CN5

Blue is the return from the trigger.

I had the gas solenoid working fine, the power supply is powered up for the motor drive, nothing is wired in to the relay yet.

I have cut the CN5 pale blue wire before it goes to trigger and connected the positive feed from the PSU to it The neg from PSU is connected to the bolt with all the connections on that is linked to the motor Neg.

If I turn the welder on now, the drive motor just whirrs slowly, and the gas solenoid is not working, so I think I have cut the wire that activates everything AC when the trigger is pulled.

I have a wiring diagram for my welder, and it is very similar to the one in the directions, but the trigger bit is not the same.

The issue is I am not sure which wire is the input wire for the dc supply to CM1, I think I need to reconnect the trigger wire and cut a different one

Please help!

Matt

 

[Mattycoops43]

This is my welder

Note the thermostat is shown in a different position, but there is nothing on the wire from the welding transformer to CM5


Just realised, the white wire from CN5 and the red wire from CN1 to the transformer are the wires going to a thermostat inside the transformer????

Still don't know which wire to put the power to though.

 

[Mattycoops43]

aaaaah. Sorted it now.

The act of writing it all down on here, clarified it in my own mind, I looked back at what I had written and realised it had to be the black wire that was the power feed, so I have re jiggered it and it's all working. Not tried welding properly yet, so no feedback, but I just struck it up against a bit of metal and it sounded very regular, so I have high hopes.

 

[rtbcomp]

Glad you sorted it - my eyes were beginning to glaze over!

Let us know how it welds.

 

[Mattycoops43]

Glad you sorted it - my eyes were beginning to glaze over!

Let us know how it welds.

Sorry if I bored you.


Thanks for everyone's help on this, I just tried it out and its like a new machine, much better than I was expecting, I tried it on some 1mm steel and it looked like a tig weld, perfect! I seriously recommend doing this mod if you have a SIP machine and are fed up of crappy bird dropping welds.

 

[rtbcomp]

Not bored - I have a SIP TopMig 950 and have been watching these threads with interest!

 

[skotl]

...I just tried it out and its like a new machine, much better than I was expecting, I tried it on some 1mm steel and it looked like a tig weld, perfect! I seriously recommend doing this mod if you have a SIP machine and are fed up of crappy bird dropping welds.

Brilliant! Really glad to hear that. It's a scary mod to do when you're just looking at circuit diagrams but, as you said, it all comes together after you've had some time to think about it. You said it was when you were writing it down, and I had exactly the same experience except for me it was to redo the circuit diagram from scratch then I figured out how it works.
And I agree with you about it being like a new machine - night and day, huh?

Good work!

 

[cracker666]

Its been two years and the mods are working a treat, nothing else was needed apart from decent wire and gas.
It really has transformed this little mig for me anyway.
The mod has proven to be reliable enough for me to fit and forget and keep plugging.