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Joined: May 2003
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We have a DC electrical service with, one bad leg. Looking to replace the conductors. My question is, as I have limited experiance with DC, what type of PPE would be required to cut, and reconnect this service live?
Or is that just a dumb question?
Mark Heller "Well - I oughta....." -Jackie Gleason
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I am sorry I can not answer your question surly someone here can, but I did want to say that it is not a dumb question. Pat yourself on the back for asking questions about safety. I only had to deal with a DC service once and the unknown made me very nervous. Bob
Bob Badger Construction & Maintenance Electrician Massachusetts
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I design a lot of DC power plants. What voltage and power levels are you talking about?
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100A -150A 240VDC Thanks!!!
Mark Heller "Well - I oughta....." -Jackie Gleason
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Why do you have to do this live? Is this so important an installation that you will risk getting blinded, burnt, killed? One thing I know about DC is that it has no neutral point, so that means you would be cutting it at full amperage. Would it be possible to attach a temporary bypass around the damaged section you wish to cut out? ~Peter
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Should not a lot different than an AC circuit of similar ratings.
Can you deenergize the source to work on it? Obviously, a DC voltmeter/indicator would be used to check for dead.
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It's a customer owned U/G service lateral prior to the disco, the utility won't drop the area, of course, or re-pull it. We are trying to get them to cut, and re-connect. But, "P" stands for premidona, in PG&E, (Our POCO, actually SF County Hetch Hechy, but they maintain it.)so they may cut, and not re-connect. (Or vise versa.)Leaving our customer without an elevator. ---------------------------------- I can kill it at Zero Amps, by killing the disco, as it already is, but the voltage in a Christy box, leaning in a hole is what I worry about. Reaching in an live 240/480VAC street box, doesn't bother me. I know the risk, and the protection level for it. With DC, I have always worked dead, and locked out.
[This message has been edited by e57 (edited 09-11-2004).]
Mark Heller "Well - I oughta....." -Jackie Gleason
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I agree, this is not a dumb question.
If the situation can not be made safe then it may be a job you don't want.
I know that is easier to say than do.
From someone who was burnt in an arc blast, I will say, living without scars and going home healthy is whats important.
We work a lot of hot situations in hospitals, but if the situation is to precarious, a "SHUTDOWN" will be scheduled for late night, early morning, holiday, etc... regardless of inconvenience or expense.
I'm sorry I don't have any real info on your original question.
Roger
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Hey Bjarney, Thanks!
00 gloves are rated for 500VAC/750VDC
Mark Heller "Well - I oughta....." -Jackie Gleason
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OK, I have to ask. What is the application for this DC service? And DC services in general.
Peter
Peter
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