SHUFFLENSHOES
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I am new and need to replace the leaky capaciters on an airco welder I need info on this thanks
- Thread starter SHUFFLENSHOES
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Wedg1e
They call me Mr. Bodge-angles
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The capacitors will probably have their rating printed on them: there'll be two figures,one being the 'capacitance', probably in microFarads - written as uF - but could be nanoFarads (nF).
The second figure will be the maximum operating voltage, which is kind of irrelevant in a welding set as they never get near the capacitors' max voltage.
They're also usually of 'electrolytic' construction... so what you might find is someting like '1000uF 400VDC' which is fairly self-explanatory - a 1000microFarad electrolytic rated for 400Volts DC.
You may also find a date code which would look like 3492; i.e. Week 32 of 1992.
When you come to refit them, they're polarised (ie should only be installed with the wiring connected one specific way around), so make sure you identify which is the (+) and which is the (-) terminal before you rip the old ones out.
In general, if you can't get exactly the same capacitance or voltage rating, it doesn't matter if you go a bit higher, but try to avoid going lower. For example 1500uF or 600VDC would be OK, but 1000uF 200VDC could run the risk of the caps being blown by voltage spikes.
The second figure will be the maximum operating voltage, which is kind of irrelevant in a welding set as they never get near the capacitors' max voltage.
They're also usually of 'electrolytic' construction... so what you might find is someting like '1000uF 400VDC' which is fairly self-explanatory - a 1000microFarad electrolytic rated for 400Volts DC.
You may also find a date code which would look like 3492; i.e. Week 32 of 1992.
When you come to refit them, they're polarised (ie should only be installed with the wiring connected one specific way around), so make sure you identify which is the (+) and which is the (-) terminal before you rip the old ones out.
In general, if you can't get exactly the same capacitance or voltage rating, it doesn't matter if you go a bit higher, but try to avoid going lower. For example 1500uF or 600VDC would be OK, but 1000uF 200VDC could run the risk of the caps being blown by voltage spikes.
shenion
Tool Pack Rat
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If you mean the HF caps, they will not be marked with a value. I assume this is for a Heliwelder 200/300 like I have or something similar vintage. I bet there is a nasty brown stain down the front of the HF panel. That is likely a carcinogenic oil. Use gloves and clean with acetone. Will slowly remove it.
The only other caps in the old Airco TIGs is the power factor caps. These should be marked with a values.
They are not marked. They are 0.002uf @ 4000V. You need the same capacitance, as close as possible (i.e. 0.0022 will work); the voltage can be higher.
Miller made most of the Airco's, the caps are shown in the parts list with a part number Miller no longer stocks. The caps out of a Miller 330-AB/P or the older Syncrowaves will work. You can try the parts lists for those from Miller's online site. They are like $100 each from what I hear.
On one, I purchased eight 0.0005 (500pf) / 10KV ceramic disc caps. and mounted them in a electronics box with two screws on top as terminals (almost exact size as original.) Used four in each, paralleled together. I then filled them with epoxy. Works better than the original.
I have helped others do similar replacements. Mine has four 0.002uf/10kv caps wired paralleled in pairs then pairs in series for 0.002uf/20KV.
As the Airco used to use 2 caps in parallel, you need to make 0.004uf at anything greater than 4000V. Higher voltage apparently makes a difference. They dissipate considerable heat. That is why I used 8 ceramic caps (the caps were 3/4" in diameter and 1/4" thick.) They just fit inside the original boxes.
I got my caps off ebay. There is a seller in China that sells them. Seems to be the only readily available of HV caps.
Also, check the spark gaps, I bet they are not the 0.008-0.010". People never adjust them and it overheats the caps and the oil boils out.
My Airco beast is 37 years young and works great. The caps and the start circuit tapped resistor are the two things that go on these.
Here's the thread where i restored mine. More info on the "My welding pages" in my sig.
Oh, and welcome to the forums
The only other caps in the old Airco TIGs is the power factor caps. These should be marked with a values.
They are not marked. They are 0.002uf @ 4000V. You need the same capacitance, as close as possible (i.e. 0.0022 will work); the voltage can be higher.
Miller made most of the Airco's, the caps are shown in the parts list with a part number Miller no longer stocks. The caps out of a Miller 330-AB/P or the older Syncrowaves will work. You can try the parts lists for those from Miller's online site. They are like $100 each from what I hear.
On one, I purchased eight 0.0005 (500pf) / 10KV ceramic disc caps. and mounted them in a electronics box with two screws on top as terminals (almost exact size as original.) Used four in each, paralleled together. I then filled them with epoxy. Works better than the original.
I have helped others do similar replacements. Mine has four 0.002uf/10kv caps wired paralleled in pairs then pairs in series for 0.002uf/20KV.
As the Airco used to use 2 caps in parallel, you need to make 0.004uf at anything greater than 4000V. Higher voltage apparently makes a difference. They dissipate considerable heat. That is why I used 8 ceramic caps (the caps were 3/4" in diameter and 1/4" thick.) They just fit inside the original boxes.
I got my caps off ebay. There is a seller in China that sells them. Seems to be the only readily available of HV caps.
Also, check the spark gaps, I bet they are not the 0.008-0.010". People never adjust them and it overheats the caps and the oil boils out.
My Airco beast is 37 years young and works great. The caps and the start circuit tapped resistor are the two things that go on these.
Here's the thread where i restored mine. More info on the "My welding pages" in my sig.
Oh, and welcome to the forums
shenion
Tool Pack Rat
- Messages
- 7,586
- Location
- Stone Mountain, GA USA
The OP was very vague on the machine.
They did make some MIG welders, I have seen the DIP-Pack 200.
Odd he did not contact me first, I get a few emails or calls a month as I have a set of web pages dedicated to mine.
BTW, arc-products.com still services these old beasts. I got parts lists from them for mine. Not bad for a 37-year old welder
They did make some MIG welders, I have seen the DIP-Pack 200.
Odd he did not contact me first, I get a few emails or calls a month as I have a set of web pages dedicated to mine.
BTW, arc-products.com still services these old beasts. I got parts lists from them for mine. Not bad for a 37-year old welder
