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#1
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Off Topic (slightly), Need Special Capacitor
Hi All,
I apologize if this is off topic, but I figured that someone may be able to supply the capacitor I'm looking for: A few years ago, I bought a complete set of RBM-4 Navy radio equipment. The set consists of a Dynamotor type power supply, a MF receiver, and an HF receiver. Up until now, each component has been working flawlessly. Each of these were made by Westinghouse in 1943. The problem occured in the Dynamotor power supply (the purpose of this power supply is to convert 12VDC to 205VDC @ 150 mA using two DC motors). While listening to the HF receiver, I noticed an increase in noise, and then suddenly, BAM! Upon opening the cabinet I found that the top of a capacitor exploded. This is an oil filled capacitor, and oil was gushing out of it rapidly. Below are the markings on this capacitor: Sprague Chlorinal 4uF 1000 VAC I can't find a replacement 4 microfarad, 1000VAC capacitor anywhere, does anyone have one, or know of a supplier? After cleaning up the oil, I found that it was damaged due to a worn out brush on one of the DC motors. I guess that excessive sparking produced some voltage spikes that killed the cap. That would also explain the noise problem (bad brush). There are six, oil filled capacitors in this Dynamotor. (2) of the Sprague 4uF Chlorinal types, (2) 10 uF GE Pyranol type, and (2) 1 uF Westinghouse "bathtub" type capacitors. All test good except for the one that exploded (internal resistance of 12K Ohm). I noticed that each of these has some oil residue around the terminals, should I replace them all, even though they test good? Another thing I noticed was the smell of the oil, it is very pungent (like a chlorine smell). Maybe some type of special military oil? PCB's? If anyone has some suggestions, I'd sure appreciate them. All of this equipment is in mint condition, and I'd like to get the Dynamotor up and running again (can't listen to the receivers without it!). Best of Regards, Ryan |
#2
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Behold, David R Brooks signaled from keyed 4-1000A filament:
A caution he a lot of old "oil" filled capacitors were filled with PCB - polychlorinated biphenyl. The name "Chlorinal" on your capacitor suggests this. PCB is highly toxic, and a known carcinogen. It is banned from current use. TAKE CARE! Bah - studies have shown canola oil to be just as dangerous to you as PCB's ;-) -- Gregg *Perhaps it's useful, even if it can't be SPICE'd* Visit the GeeK Zone - http://geek.scorpiorising.ca |
#3
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I recently was looking for caps in my area and called a surplus store in
Hillsboro, OR. called Wacky Willy's. I live in Durham, OR. which is why I was calling them. I asked if they had the caps I was looking for, 40 and 80 mfd at 350v and 400v. No go on the ones I was looking for but he started to name off a few high voltage ones he did have and I remember him saying something about 1000v caps. I don't remember what mfd value he mentioned though. You might try using qwestdex.com to get the number and give them a call and ask. Doubt they will ship but if they have them I can probably go get them and ship them to you. Later, Bryan "Ryan Inman" wrote in message om... Hi All, I apologize if this is off topic, but I figured that someone may be able to supply the capacitor I'm looking for: A few years ago, I bought a complete set of RBM-4 Navy radio equipment. The set consists of a Dynamotor type power supply, a MF receiver, and an HF receiver. Up until now, each component has been working flawlessly. Each of these were made by Westinghouse in 1943. The problem occured in the Dynamotor power supply (the purpose of this power supply is to convert 12VDC to 205VDC @ 150 mA using two DC motors). While listening to the HF receiver, I noticed an increase in noise, and then suddenly, BAM! Upon opening the cabinet I found that the top of a capacitor exploded. This is an oil filled capacitor, and oil was gushing out of it rapidly. Below are the markings on this capacitor: Sprague Chlorinal 4uF 1000 VAC I can't find a replacement 4 microfarad, 1000VAC capacitor anywhere, does anyone have one, or know of a supplier? After cleaning up the oil, I found that it was damaged due to a worn out brush on one of the DC motors. I guess that excessive sparking produced some voltage spikes that killed the cap. That would also explain the noise problem (bad brush). There are six, oil filled capacitors in this Dynamotor. (2) of the Sprague 4uF Chlorinal types, (2) 10 uF GE Pyranol type, and (2) 1 uF Westinghouse "bathtub" type capacitors. All test good except for the one that exploded (internal resistance of 12K Ohm). I noticed that each of these has some oil residue around the terminals, should I replace them all, even though they test good? Another thing I noticed was the smell of the oil, it is very pungent (like a chlorine smell). Maybe some type of special military oil? PCB's? If anyone has some suggestions, I'd sure appreciate them. All of this equipment is in mint condition, and I'd like to get the Dynamotor up and running again (can't listen to the receivers without it!). Best of Regards, Ryan |
#4
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"Fabio Berutti" wrote in message ...
Have a look he http://www.plasticcapacitors.com/product_index.html As a chemical engineer I recommend You to wear rubber gloves when handling the exploded, PCB-containing old capacitor and to dispose of it properly (it should be sent to a special dump for highly toxic substances). Remember that carcinogenics do not have a "minimum risk threshold" (unless You set to absolutely 0). Nowadays oil-filled capacitors use EPA-approved oils. Ciao Fabio I am very familar with PCB's, I worked at a transformer plant for years, and we used "Elemex" PCB containing oil to fill the transformer casing. Many workers (including myself) were up to their armpits in oil, working on coils, etc. None of us ever got sick or anything. As far as I know, there were never any reported cases of cancer or other disease from exposure to chlorinated hydrocarbons. The company has since reopened, and they are using a non-PCB containing oil. All of the left over contaminated oil is stored in three large tanks near company property. PCB's and other chemicals seeped into the water supply within the plant, and the plant water supply has been turned off until the contamination can be cleaned up. There is no indoor water running (restroom, water fountains, sinks, etc) due to the contamination. Just about everything in the plant was contaminated with the oil, especially the floor in the Vapor Phase department. All employees must use the outdoor restroom facilities. To this day, the contamination isn't cleaned up. Inside the plant, you can still smell the oil residue. If PCB's were truly dangerous, I'm sure that one of us would've gotten sick or something. All of my fellow employee's that worked with me in large assembly are still alive and well, along with the employee's who worked in the vapor phase department. I highly doubt that PCB oil is dangerous (unless burned). And I think it's a damn shame that all of those transformers we built are being destroyed and replaced because they contain PCB oil (and all of them are in perfect working order, I can't say the same for the new transformers). I won't mention the company's name because they would probably try to sue me if they read this (they build junk now). Best Regards, Ryan |
#5
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Wacky Willies is a great place! Theres another store in NW,about 23rd
and Vaughn. Lots of goodies! "Bryan McGivney" wrote in message ... I recently was looking for caps in my area and called a surplus store in Hillsboro, OR. called Wacky Willy's. I live in Durham, OR. which is why I was calling them. I asked if they had the caps I was looking for, 40 and 80 mfd at 350v and 400v. No go on the ones I was looking for but he started to name off a few high voltage ones he did have and I remember him saying something about 1000v caps. I don't remember what mfd value he mentioned though. You might try using qwestdex.com to get the number and give them a call and ask. Doubt they will ship but if they have them I can probably go get them and ship them to you. Later, Bryan "Ryan Inman" wrote in message om... Hi All, I apologize if this is off topic, but I figured that someone may be able to supply the capacitor I'm looking for: A few years ago, I bought a complete set of RBM-4 Navy radio equipment. The set consists of a Dynamotor type power supply, a MF receiver, and an HF receiver. Up until now, each component has been working flawlessly. Each of these were made by Westinghouse in 1943. The problem occured in the Dynamotor power supply (the purpose of this power supply is to convert 12VDC to 205VDC @ 150 mA using two DC motors). While listening to the HF receiver, I noticed an increase in noise, and then suddenly, BAM! Upon opening the cabinet I found that the top of a capacitor exploded. This is an oil filled capacitor, and oil was gushing out of it rapidly. Below are the markings on this capacitor: Sprague Chlorinal 4uF 1000 VAC I can't find a replacement 4 microfarad, 1000VAC capacitor anywhere, does anyone have one, or know of a supplier? After cleaning up the oil, I found that it was damaged due to a worn out brush on one of the DC motors. I guess that excessive sparking produced some voltage spikes that killed the cap. That would also explain the noise problem (bad brush). There are six, oil filled capacitors in this Dynamotor. (2) of the Sprague 4uF Chlorinal types, (2) 10 uF GE Pyranol type, and (2) 1 uF Westinghouse "bathtub" type capacitors. All test good except for the one that exploded (internal resistance of 12K Ohm). I noticed that each of these has some oil residue around the terminals, should I replace them all, even though they test good? Another thing I noticed was the smell of the oil, it is very pungent (like a chlorine smell). Maybe some type of special military oil? PCB's? If anyone has some suggestions, I'd sure appreciate them. All of this equipment is in mint condition, and I'd like to get the Dynamotor up and running again (can't listen to the receivers without it!). Best of Regards, Ryan |
#6
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"Gregg" wrote in message
... Bah - studies have shown canola oil to be just as dangerous to you as PCB's ;-) - Seconded - most banned chlorinated hydrocarbons are EPA scare-mongering. Kinda like nuclear power. Tim -- In the immortal words of Ned Flanders: "No foot longs!" Website @ http://webpages.charter.net/dawill/tmoranwms |
#8
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Hi all -
I have a bunch of oil caps rated from 1kv to 6kv - , 1. to 8Mf - they're fairly common in old lab HV power supplies & mil. gear, which is available for next-to-nothing... The only problem is finding the space for those things - a 6K 2Mf cap is about the size of half a carton of cigs.... -dim "Bob Hedberg" wrote in message ... Hi I have a Pyramid 4mf 1000vdc cap you can have, but it's not going to be high enough if you need 1kvAC. You could connect three 12Uf 630v caps in series for 4uf / and at least 1kva. You could use Solen metalized pp caps, which should be accurate enough not to need equalizing resistors, though I don't know for sure. Maybe someone here has experimented with this. Electrolytics in series usually should have dropping resistors to equalize the voltage, but film caps may not need them. Three should give you 1890vdc protection, which gives at least 450 vdc margin over the max vdc you should see with 1kvac. (I'm figuring 1414vdc max). The only 12uf caps I see (and the cheapest) are 12Uf/630vdc Angela (Solens) caps at $4.75 each at Angela.com. They're made by the same folks who make Solens. They're non-polarized, and so should handle your application. If there is some inherent danger of connecting series caps for this application, please let us know. Bob Hedberg (Ryan Inman) wrote: Hi All, I apologize if this is off topic, but I figured that someone may be able to supply the capacitor I'm looking for: A few years ago, I bought a complete set of RBM-4 Navy radio equipment. The set consists of a Dynamotor type power supply, a MF receiver, and an HF receiver. Up until now, each component has been working flawlessly. Each of these were made by Westinghouse in 1943. The problem occured in the Dynamotor power supply (the purpose of this power supply is to convert 12VDC to 205VDC @ 150 mA using two DC motors). While listening to the HF receiver, I noticed an increase in noise, and then suddenly, BAM! Upon opening the cabinet I found that the top of a capacitor exploded. This is an oil filled capacitor, and oil was gushing out of it rapidly. Below are the markings on this capacitor: Sprague Chlorinal 4uF 1000 VAC I can't find a replacement 4 microfarad, 1000VAC capacitor anywhere, does anyone have one, or know of a supplier? After cleaning up the oil, I found that it was damaged due to a worn out brush on one of the DC motors. I guess that excessive sparking produced some voltage spikes that killed the cap. That would also explain the noise problem (bad brush). There are six, oil filled capacitors in this Dynamotor. (2) of the Sprague 4uF Chlorinal types, (2) 10 uF GE Pyranol type, and (2) 1 uF Westinghouse "bathtub" type capacitors. All test good except for the one that exploded (internal resistance of 12K Ohm). I noticed that each of these has some oil residue around the terminals, should I replace them all, even though they test good? Another thing I noticed was the smell of the oil, it is very pungent (like a chlorine smell). Maybe some type of special military oil? PCB's? If anyone has some suggestions, I'd sure appreciate them. All of this equipment is in mint condition, and I'd like to get the Dynamotor up and running again (can't listen to the receivers without it!). Best of Regards, Ryan Bob H. Just grab that plate in one hand, the chassis in the other, and FEEL the power of tube audio!!! (not literally, of course, just kidding. DON'T DO THAT!) |
#9
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Shiva,
The caps don't have to be inside the same chassis: they can be located outboard. I recall seeing an outboard cap box once for a Hafler amp that was as big as the amp. I believe there are some techncal safeguards that would need to be taken before you hook a huge capacitance to your power supply to prevent a problem from the huge turn on current inrush, but someone else would have to help with that. Wylie Williams "Shiva" wrote in message ... Hi all - I have a bunch of oil caps rated from 1kv to 6kv - , 1. to 8Mf - they're fairly common in old lab HV power supplies & mil. gear, which is available for next-to-nothing... The only problem is finding the space for those things - a 6K 2Mf cap is about the size of half a carton of cigs.... -dim "Bob Hedberg" wrote in message ... Hi I have a Pyramid 4mf 1000vdc cap you can have, but it's not going to be high enough if you need 1kvAC. You could connect three 12Uf 630v caps in series for 4uf / and at least 1kva. You could use Solen metalized pp caps, which should be accurate enough not to need equalizing resistors, though I don't know for sure. Maybe someone here has experimented with this. Electrolytics in series usually should have dropping resistors to equalize the voltage, but film caps may not need them. Three should give you 1890vdc protection, which gives at least 450 vdc margin over the max vdc you should see with 1kvac. (I'm figuring 1414vdc max). The only 12uf caps I see (and the cheapest) are 12Uf/630vdc Angela (Solens) caps at $4.75 each at Angela.com. They're made by the same folks who make Solens. They're non-polarized, and so should handle your application. If there is some inherent danger of connecting series caps for this application, please let us know. Bob Hedberg (Ryan Inman) wrote: Hi All, I apologize if this is off topic, but I figured that someone may be able to supply the capacitor I'm looking for: A few years ago, I bought a complete set of RBM-4 Navy radio equipment. The set consists of a Dynamotor type power supply, a MF receiver, and an HF receiver. Up until now, each component has been working flawlessly. Each of these were made by Westinghouse in 1943. The problem occured in the Dynamotor power supply (the purpose of this power supply is to convert 12VDC to 205VDC @ 150 mA using two DC motors). While listening to the HF receiver, I noticed an increase in noise, and then suddenly, BAM! Upon opening the cabinet I found that the top of a capacitor exploded. This is an oil filled capacitor, and oil was gushing out of it rapidly. Below are the markings on this capacitor: Sprague Chlorinal 4uF 1000 VAC I can't find a replacement 4 microfarad, 1000VAC capacitor anywhere, does anyone have one, or know of a supplier? After cleaning up the oil, I found that it was damaged due to a worn out brush on one of the DC motors. I guess that excessive sparking produced some voltage spikes that killed the cap. That would also explain the noise problem (bad brush). There are six, oil filled capacitors in this Dynamotor. (2) of the Sprague 4uF Chlorinal types, (2) 10 uF GE Pyranol type, and (2) 1 uF Westinghouse "bathtub" type capacitors. All test good except for the one that exploded (internal resistance of 12K Ohm). I noticed that each of these has some oil residue around the terminals, should I replace them all, even though they test good? Another thing I noticed was the smell of the oil, it is very pungent (like a chlorine smell). Maybe some type of special military oil? PCB's? If anyone has some suggestions, I'd sure appreciate them. All of this equipment is in mint condition, and I'd like to get the Dynamotor up and running again (can't listen to the receivers without it!). Best of Regards, Ryan Bob H. Just grab that plate in one hand, the chassis in the other, and FEEL the power of tube audio!!! (not literally, of course, just kidding. DON'T DO THAT!) |
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