PDA

View Full Version : Caps.



George Hodge
07-29-2009, 09:06 PM
Where can a person find capacitors for a Linde 225 wire feed welder?I need 5,Sprague 9800mfd,50volt,DC,screw terminal caps.The old ones were not screwed down tight and arced.Probably need to replace them all at once.Any ideas are appreciated. Oh,they're 4 1/2" high,2"in dia. Thanks,George

macona
07-30-2009, 03:59 AM
There is no exact replacement for the caps in that machine. With the age of that machine you will want to replace all of them though. It was probably not loose caps. Most likely one shorted out and the heat from it arced out the screw connection. (I used to be a service tech for Airgas)

For the 225s that I have replace the caps on I looked though the catalog from Newark and found something close. The main things you are looking for are Voltage (Equal or greater) Capacitance. (Equal as you can get, err on the high side) and Spacing between studs and diameter. All the new caps are smaller for the given capacitance thanks to newer tech. So the ones I ended up getting were about 1-1/2" shorter. No big deal.

If you tell me what the screw spacing is and diameter I will look through the catalog and try to figure out which ones I got.

George Hodge
07-30-2009, 08:07 PM
Macona, the threaded holes are 7/8in.apart,the diameter is 2in.and they're 5 5/8 tall. I'll probably need all 5 of them. If you have a source,I'd really appreciate it!
Thanks,George

macona
08-09-2009, 02:24 AM
Sorry it took so long but here they are:

http://www.newark.com/cornell-dubilier/cgr103u050v4c/aluminum-electrolytic-capacitor/dp/69K1780

They are shorter like I mentioned. They hang fine by the copper buss bars though. Newark seems to have the best price.

-Jerry

macona
08-09-2009, 02:28 AM
These guys have them for #15 each:

http://www.tedss.com/CGR103U050V4C/

George Hodge
08-09-2009, 02:01 PM
Thanks Macona.
Monday I'll give them a call! George

George Hodge
08-12-2009, 08:51 PM
Macona,ordered them today! Should be here this week!
Thanks,George

uncrichie
08-15-2009, 06:32 PM
Something else that should be looked at when replacing capacitors is the environmental temperature. There are several temp ranges for electrolytic caps. Also the current rating of the original cap should be followed. Neglecting either of the above will result in shorter lifespan or immediate failure upon use. Unfortunately price comes into play. Usually the cheaper caps have the inferior ratings but not always. Just something to remember when replacing large electrolytics. Uncrichie.

George Hodge
08-15-2009, 09:02 PM
Thanks Uncritchie, today's Saturday and they haven't come yet.I think the only difference will be these new capacitors will be 1" shorter and 10,000 mfd.instead of 9800mfd.
George

uncrichie
08-16-2009, 11:28 AM
Your welcome George. If you google "Ripple Current Capacity" for capacitors you'll get more info. The secret is to finding what the original capacitor ripple current capacity is/was. The ripple capacity is less critical in the 10,000 ufd than in say 100 ufd range but its still important. I think you'll be OK in what you purchased. I just threw this info out there for others who might want more info on capacitors. Obviously the critical parameters are capacitance and voltage but current carrying capability is also important.

George Hodge
08-17-2009, 09:16 PM
Macona&Uncrichie, They came in today and work fine!!! I appreciate having a source like this forum,priceless!
Thank you both! George

uncrichie
08-25-2009, 08:11 PM
Thanks for letting us know the end result. Glad to here it worked out. Uncrichie.