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GrahamGKD
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My understanding is that it is the capacitance that is the operative part of the capacitor (specified in farads or micro farads) and that the voltage is the insulation voltage it is designed / tested for. If you replace with a capacitor of the same general type which has the same capacitance but a higher voltage I don't see that it should make any difference (a bit like if you were to replace a pipe with one of the same inside diameter but designed to work under a higher pressure). I'm not sure what type of capacitors are used in welding equipment but note that some types of capacitor are designed to work with polarity - i.e. they have positive and negative terminals.
If you were to replace a capacitor with one rated for a lower voltage you might be in trouble (the pipe analogy holds true)!!
Graham.
If you were to replace a capacitor with one rated for a lower voltage you might be in trouble (the pipe analogy holds true)!!
Graham.
Richie_asg1
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Yes you can use one rated higher, but Capacitance should be close to that specified.
Voltage rating is - as said above is just down to the materials used in construction, so it's the insulation that wil break down if the voltage exceeds that stated.
There are different materials used in manufacture, and some are better suited for damp environments.
Electrolytic capacitors must be installed the correct way around - or they will explode.
They are normally used for current smoothing operations, and generally, the higher the capacitance - the smoother the ripple will be from a rectified sine wave.
So to reduce "buzz" from a dirty DC supply, you can double-up with capacitors or instal a larger one.
The reason why manufacturers use smaller ones is purely cost and size issues.
Capacitors will also reduce arcing from motors, so virtually anything will help this as long as they are rated higher than the supply.
The problems you get with larger capacitors is that they act as little storage cells, so you will get a run-on with motors.
A bit more complicated solution to this (new) problem, is to use a trigger switch onto a relay which will cut the supply instantly, but you should also then arrange for the capacitor charge to go into a meaty resistor instead, and use electric braking on the motor as well - by shorting out the poles through a similar resistor.
Voltage rating is - as said above is just down to the materials used in construction, so it's the insulation that wil break down if the voltage exceeds that stated.
There are different materials used in manufacture, and some are better suited for damp environments.
Electrolytic capacitors must be installed the correct way around - or they will explode.
They are normally used for current smoothing operations, and generally, the higher the capacitance - the smoother the ripple will be from a rectified sine wave.
So to reduce "buzz" from a dirty DC supply, you can double-up with capacitors or instal a larger one.
The reason why manufacturers use smaller ones is purely cost and size issues.
Capacitors will also reduce arcing from motors, so virtually anything will help this as long as they are rated higher than the supply.
The problems you get with larger capacitors is that they act as little storage cells, so you will get a run-on with motors.
A bit more complicated solution to this (new) problem, is to use a trigger switch onto a relay which will cut the supply instantly, but you should also then arrange for the capacitor charge to go into a meaty resistor instead, and use electric braking on the motor as well - by shorting out the poles through a similar resistor.
I was wondering if it would hold more voltage for better welds. On a arc welder ... specs say its a 240v capacitor and i saw some 650v on ebay kinda cheap.
Mirco waves 2200v capacitors that hold electricity... Is it like the welder when shut off will still spark for a second?
maybe it would loss power trying to fill up a bigger capacitor?
Mirco waves 2200v capacitors that hold electricity... Is it like the welder when shut off will still spark for a second?
maybe it would loss power trying to fill up a bigger capacitor?
shenion
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There is a lot more than just voltage. For high-power devices, the current rating and temperature specs are more critical. It really depends on how it is used.
Oil-filled, metal can caps can handle considerable current/power. While regular film caps will likely just brun out.
For example, a motor un capacitor is designed to run continuously while a start capacitor is only designed to run a few seconds.
Is this an input side cap (power factor correction) or output filter?
Oil-filled, metal can caps can handle considerable current/power. While regular film caps will likely just brun out.
For example, a motor un capacitor is designed to run continuously while a start capacitor is only designed to run a few seconds.
Is this an input side cap (power factor correction) or output filter?
Not sure... kinda new at this... i'm more of a mechanic then a electrician.
heres specs of welder...
http://www.clarkeusa.com/manuals/we/WE6519.pdf
heres specs of welder...
http://www.clarkeusa.com/manuals/we/WE6519.pdf
Just kind of bugs me it stats it welds 6011 2.4 /3/32 rods....
It welds them but you have to hover rod alittle over 1/8 and theres not much penetration.
5/64 rods work perfect tho. welding a 1/8 plate it will hot red the plate about a inch wide.
still better than my 70amp lincon ... this is a clark131 output 130amps .... more like 90 amps.
6011 3/32 rods says 85amps to run them. barely
My friend runs them at 105amps I think he said.
o well I don't weld much its just for small hobbies.
It welds them but you have to hover rod alittle over 1/8 and theres not much penetration.
5/64 rods work perfect tho. welding a 1/8 plate it will hot red the plate about a inch wide.
still better than my 70amp lincon ... this is a clark131 output 130amps .... more like 90 amps.
6011 3/32 rods says 85amps to run them. barely
My friend runs them at 105amps I think he said.o well I don't weld much its just for small hobbies.
Richie_asg1
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I bought a 15A stick welder by SIP. Works fine up to 4mm.
I think that cap is more for supression rather than power handling.
One thing I did find annoying, was using 2,5mm rods, and doing continous welding (on a Landrover) - it would cut-out with overheating problems.
What I needed - was a Turbo.
What I made - was cheap
I stripped a Microwave oven - and nicked the fan from it, and mounted it on the rear of the welder inside to give forced cooling of the coils.
Next up was a simple temperature switch for about £1.20, that was NO, closing at 60 degrees. This I bonded onto the other side of the welding coils with JB weld - which is a steel loaded epoxy.
I wired it in series with the main power switch - taking the supply from the unswitched side. This means the fan will still run on after I switch it off untill it cools.
Now I can weld without it tripping out on me. - and it just cost me £1.20
I think that cap is more for supression rather than power handling.
One thing I did find annoying, was using 2,5mm rods, and doing continous welding (on a Landrover) - it would cut-out with overheating problems.
What I needed - was a Turbo.
What I made - was cheap
I stripped a Microwave oven - and nicked the fan from it, and mounted it on the rear of the welder inside to give forced cooling of the coils.
Next up was a simple temperature switch for about £1.20, that was NO, closing at 60 degrees. This I bonded onto the other side of the welding coils with JB weld - which is a steel loaded epoxy.
I wired it in series with the main power switch - taking the supply from the unswitched side. This means the fan will still run on after I switch it off untill it cools.
Now I can weld without it tripping out on me. - and it just cost me £1.20
Yes that is right and this one is only 20Mf.
Have seen a lot of AC machines with caps of various capacitance ratings
Cheers
Found some 3/32 rods that weld very good
powerweld rods the 3/32 runs at 75A..... Others ran at 85 and 90A
Got a 5 pound box for 9.99
I Changed welder rod holder to a 400A when buying welder and not sure if its my imagination but I thought the 200A holder made welder alittle stronger.
Could using a smaller clamp help on a not so strong welder.... would it take more amps because 400A holder it a big chunk of metal?
powerweld rods the 3/32 runs at 75A..... Others ran at 85 and 90A
Got a 5 pound box for 9.99
I Changed welder rod holder to a 400A when buying welder and not sure if its my imagination but I thought the 200A holder made welder alittle stronger.
Could using a smaller clamp help on a not so strong welder.... would it take more amps because 400A holder it a big chunk of metal?
