old sip ideal 150

[ian mcdonald]

hi chaps hope you can help me the contactor has stopped contacting but everything else working fine i replaced it but just the same ,checking and following wires it seems to work from the same section of the circuit as the gas switch which is working fine i just cannot work out how one half ie gas swich works and other half wont ,cheers for any help, ian i looked through old forums and mine is the one with a 12 pin plug and the the contactor and gas swich are on 48 volt side

 

[ian mcdonald]

forgot to add if anyone knows some one up here tyne and wear who fixes them if i cannot cope i would be gratefull cheers ian

 

[mike 109444]

Welcome Ian
The coil that should operate the contacts of the "contactor" feeds through a thermal cut out (item 13 on diagram) If the welder is cool/cold and it still does not operate then the cut out could be duff (open circuit) contactor or the wires going to and from the coil (red line on diagram) could have a break, the coil could be open circuit, poor/bad connection on 12 pin plug or socket.
A few things for you to try / check

 

[ian mcdonald]

cheers for quick replycould you give me a clue where that is or what it looks like as i do think it sounds like the right type of solution i could attach a pic of my welder if you think it will make things easyer to describe cheers, ian ,sorry for any spellins just back from pub

 

[mike 109444]

The thermal cut out may be mounted to the contactor (not sure).
You will need to trace the wires from the contactor back to the aux transformer (the one with the choc block connectors on it, top left) It should be possible to then figure the wire going from Aux to contactor then through cut out and onto the 12 pin connector.
ps don't use my colours from the diagram as the correct colours !

 

[ian mcdonald]

mine looks just like the picture but has a different contactor its been changed some time in past so when it stopped working i replaced it with a new one of same type didnt fix it though, i will try what you suggest in following wires and let you no how i get on ,fingers crossed as i could realy do with it working cheers for your help ,ian

 

[ian mcdonald]

does that mean i am looking for somewhere between pin 3 and the aux block ,sorry if i sound thick, cheers ian

 

[mike 109444]

does that mean i am looking for somewhere between pin 3 and the aux block ,sorry if i sound thick, cheers ian

Yes.
With the welder UNPLUGED cut the tie wrapes that hold the cables togeather between the contactor and the aux transformer. Then if the aux transformer is marked by the choc block (the lable just above the bottom choc block?) as to the voltages (my pic is not clear enough for me to tell) You are looking for the 48v connection, As you say the gas valve is working then there should be 2 wires going into that connection (diagram shows it splitting away from the choc block, red and green on my diagram but they would use the choc bloc).
If you identify the ONE of the TWO wire that goes from this choc bloc connection to the contactor that is the red line in diagram.
Loosen the screw that holds theses TWO wires and pull out the ONE going to the contactor. Now if you meter each end of this wire (one end at choc bloc and other end at contactor. Meter should be set on a low Ohms setting ie 100 or 200 ish depending on your meter. You should see a dead short (00.0 ish on a digital meter) as you are metering a length of cable. If correct you can keep the meter connect on the choc block end of cable and now meter the other side of the coil built into the contactor, should be same size and maybe same colour cable. Again meter still set on low setting, you should see on meter a low reading of 5 to 80 ish ohms as this will be the coil in the contactor which will have SOME resistance. If correct then move the meter lead from the choc bloc wire to the pin 3 of the 12 pin plug and keep other meter lead on the other side connection of the contactor, should see dead short again.
Sorry if this all looks a bit long winded but this would take 5 mins to do but 30 mins to write up!!
Not sure of your level of electrical-electronic-mechanical knowledge.
Let us know the results.
Still not sure where the cut out is, it may be built into the contactor? or in the wire going from contactor to 12 pin plug

 

[ian mcdonald]

i hav had another go and done all that evey thing conected as it should be found the thermal cut out it is in red wire that gos from choc block to 13 pin plug and it just tucks into the transformer tested it and it has cotinuity cut one of wires going to it and gas valve and wire feed stopped working reconected and there fine the prob as i see it is that the connecor and the gas valve are energised by the same section and evan wired to same part of choc block so why one should work and not the other baffles me i wonder if there is a way of testing if there is 48 volts incase the gas valve can operate on less than 48 volts but the connector wont ,bt the way if i push in the connector in manualy and pull trigger everything works fine i just need the contactor to jump in thanks for any help ,ian , as i slowly go barmy looking at this saying both things are wired togeather but only one will work

 

[mike 109444]

If you look at the aux transformer it maybe marked up with 48V and along side it 0V ( there maybe another 0V further along with a 24V. This is not the one you need as it's the one for the 24V.
If you set your meter to AC volts and meter between the 48V and it's 0V then you should see between 45 to 55vAC. If ok then UNPLUG WELDER FROM MAINS
Now disconnect one of the wires on the coil of the contactor either at X oy Y on pic. Now set meter to Ohms on a low range say 100 or 200. Then put one meter lead on one side of contactor coil X and one lead on other side of the coil Y ( not the wire you just disconnected!) You should get a reading of between 5 or less to 80 Ohms The value of the coil maybe marked on the side of the contactor. I think this is where the fault is and recon you will get an open circuit reading ie now't on meter. If you get a good reading the There is a remote chance that the gas valve coil is failing and drawing the current that should be shared between the two coils. To check reconnect the wire removed in above test and disconnect the wire going from the choc block to the gas valve. Now power welder on and see if the contactor operates (gas valve won't because you have disconnected it!).
Let us know the results of above test
Note the circuit on the pcb is what completes the circuit for the two coils

 

[ian mcdonald]

hi chaps its sorted and heres the story ran tests as mike sugested weird results decided my meter must be playing up invested in new one same results and here is what they were bridgeing 24v to the zero got 12.5 (by the way this zero wasent marked as such no bloody zero marked at all but it was the same loop in aux ) bridgeing 48v to the zero got 3v decided it must be aux problem talked to nice guys at yor************ (e bay shop)verry informative they also own co.called tecark.com who made me a suitable aux transformer in 2 days cost me 118.00 inc postage ,put it all togeather and still nothing proper scratch the head time rechecked the new contactor that i had fitted to start with and proper circuit ie. continuous decided to conect it direct to 48v and 0 still nothing, bought another one from technical ark ltd £25 inc postage fitted it and bingo all fine i thought i would write in full so you could see what i got up to had me propper dun in thanks for your help and diagrams and no i do not have anything to do with them i live in newcastle they are in york i am just a pleased customer though i will say they have a fantastic supply of bits for old welders if you are looking for parts and they make there own pcbs for older welders i know this because i thought that was the next thing i would have to buy( bloody contactor )cheers i hope some of my research will be of use to your members

 

[skotl]

Glad to hear you got it fixed, Ian. Do you think the aux transformer was a red herring, then? Shame to blow a ton on it if it was

It's also good to hear of a company that can provide custom made spares, especially given the price that SIP charges.

One point I'd make is that I typed in "tecark.com" and it's some property developer in Spain! It wasn't hard to find the real company but you may want to edit that part of your post out.

Cheers
Scott

 

[ian mcdonald]

mig

hi chaps another update the transformer was dodgy as well after i had taken it off i connected it up direct on bench not attached to anything it sat for 5 min then totaly melted and blew fuse the co that supplied the bits was called york welding same people different co and very helpfull on phone the guy looked up wireing diagram when i was on phone and talked me through stuff then emailed it hope this is of some help to your members they seem to be able to make or get stuff for most old welders just to say again no connection with them i am just a pleased customer

 

[ian mcdonald]

i did try to put in e bay shop but the anti spam software blanked it out dunno if you no how to get round that as i am sure other members would find it helpfull