I am looking at the lower circuit board of a CT312 multifunction welder. The is a component that looks like an adjustable spark gap. Can someone identify this and explain the function. The welder is only giving very low power out. It was bought from New and worked fine until put away 18 months back, any suggestions please?
- Thread starter filbert
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Hello and welcome to the Forum !
According to this earlier thread, the CT312 does indeed contain a spark gap:
The function of that component is to create a high voltage, high frequency, low current power source to ionise the air and enable the initiation of an arc.
According to this earlier thread, the CT312 does indeed contain a spark gap:
Jasic CT 312 DC Plasma not Arching
Hiya Last time I had been on the forum, I received brilliant help with a capacitor replacement and I hope the wise-men can help me again! Been working with this welder since then, only replacing the on-off switch once! My plasma cutter does not arc! I have not used the plasma function for...
www.mig-welding.co.uk
skotl
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What Eddie says.
Which function isn't working (or is it all of them)? The spark gap is only used on the plasma side and, being literally just two bits of metal and some air, won't be a reason for failure.
Have you had the boards out and hunted around for any soot on the components or boards?
If one of the IGBTs ("transistors", kinda) have failed then it's unlikely you'll spot it without removing them from the board and testing each of them.
Which function isn't working (or is it all of them)? The spark gap is only used on the plasma side and, being literally just two bits of metal and some air, won't be a reason for failure.
Have you had the boards out and hunted around for any soot on the components or boards?
If one of the IGBTs ("transistors", kinda) have failed then it's unlikely you'll spot it without removing them from the board and testing each of them.
Test those big resistors with your multimeter on ohms.
You can Google the colour codes to establish their value.
Common for these to go open circuit. .
Wouldn't hurt to go over with a soldering iron at their joints.
Some times you can see what looks like a good joint has the solder not wanting to stick to the lead of resistor. .
Remove resistor and scratch leads surface with the back of a parcel knife.
Should see the solder take when you re-solder in.
You can Google the colour codes to establish their value.
Common for these to go open circuit. .
Wouldn't hurt to go over with a soldering iron at their joints.
Some times you can see what looks like a good joint has the solder not wanting to stick to the lead of resistor. .
Remove resistor and scratch leads surface with the back of a parcel knife.
Should see the solder take when you re-solder in.
