Wire ratings - AC or DC?

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Gaz
Posts: 1146
Joined: Tue Aug 25, 2009 6:27 am

Wire ratings - AC or DC?

Post by Gaz »

Does anyone know if wire ratings are for AC or DC (i.e. 600v wire)? I have some 600v wire and a 650vdc B+, and wondering if I should use it or not to connect the plates...
Jana
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Joined: Sun Sep 07, 2008 10:40 pm
Location: Minnesota

Re: Wire ratings - AC or DC?

Post by Jana »

If it was me (keep in mind I have been known to drive cars into the river), I would probably use the wire if it was my own build. But, I would want to give those wires some breathing room too. I wouldn't bunch them with other wires, especially ground or low voltage potential wires, nor would I lay them right on the chassis. I would want to have them off the chassis 1/4 inch or more. How long are they? You could add a layer of shrink tube over those wires to add more insulation. If it is a build for someone else, I would try to source some properly rated wire.
Gaz
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Joined: Tue Aug 25, 2009 6:27 am

Re: Wire ratings - AC or DC?

Post by Gaz »

Yeah, Jana, I was having the same line of thinking of you, but since the amp is for a friend (who does not live nearby), I think I'm just gonna be patient and order some 1000v stuff. That idea about the heat shrink is really smart though.
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Phil_S
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Location: Baltimore, MD

Re: Wire ratings - AC or DC?

Post by Phil_S »

I'd argue that heat shrink is not a solution. If the wire is carrying 650V and melts under the heat shrink, what's going to happen? I don't want to learn the answer the hard way. See if Steve at Apex Jr. has some 1000V wire. Generally, he'll sell small quantities at reasonable prices. You should make a phone call, not send email.
Zippy
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Joined: Tue Apr 25, 2006 11:18 pm

Re: Wire ratings - AC or DC?

Post by Zippy »

Gaz wrote:Does anyone know if wire ratings are for AC or DC (i.e. 600v wire)? I have some 600v wire and a 650vdc B+, and wondering if I should use it or not to connect the plates...
The classic test is DC but what matters is the insulation break down with respect to peak potential.

I, too, would advocate for wire with the proper rating for the application.
Jana
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Joined: Sun Sep 07, 2008 10:40 pm
Location: Minnesota

Re: Wire ratings - AC or DC?

Post by Jana »

As I said, if the build was for someone else, I would use the proper wire. That being said, with the proper spacing between other wires/ground/etc., bare wire would work.

But, to argue your point about the heat shrink, it's not the voltage that is going to heat the wire and melt the insulation, it is the current. If the wire is rated at 1000 volts but is still too small a gauge for the current, it is going to melt.
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