Wire Voltage Rating

[big_teee]

I ordered parts for my 6V6 amp build.
I ordered some red and black wire for B+ use.
The web site said the wire was 600v rated.
When I got the wire it has 300v all over the red and black wire.
I emailed them about the wire, and was told though it says 300v it is actually 600v wire.
something about the rating AWM.
Anyone know anything about this?
T

[Jazz P Bass]

What gage is the wire?

I had thought that wire was typically rated in current capacity, in Amps.

[tedmich]

I believe the insulation dictates the voltage rating, 300V rated has thinner/weaker insulation that 600V rated.

[jmaf]

It's 300VAC and 600 VDC.

AC is harder to insulate.

[big_teee]

I just don't want any arcing.
Wire size determines current capacity, and insulation determines voltage limits.
It is HTPVC-22-STR 22gauge, low current, but 425V DC or so.
The wire has a Mil-Spec code: M16878.
Maybe with the mil spec code we can figure out the voltage rating.
Thanks,
T

[jmaf]

Well The Google says it's a Teflon insulated silver wire for 1kV. The good stuff!

If it's indeed PTFE you can use it under salt water and it won't ever arc.

MIL-W-16878 Catalog Pages.pdf

[tedmich]

its not AC/DC its the insulation: PVC 20AWG 10/30 strand rated at 300V is 0.010-0.016" insulation, 600V is 0.032" insulation

There's over 30 types of M16878 wire!
MIL-W-16878 (M16878) Hook Up Wire from Allied Wire and Cable Distributor of MIL Spec Wire

[big_teee]

it is M16878 / 1-BGE-6-COLOR
Here is the wire I bought.
I just needed a few feet, and I ordered it with other parts.
https://tubedepot.com/products/22-ga...ature-pvc-wire
T
** It appears to be this one, and it says it is 600v
http://www.awcwire.com/productspec.a...=mil-w-16878/1

[g1]

Then the question remains, why is it labelled as 300V (or why are they only allowed to label it as such) ?

[g1]

I saw a different wire that was rated 1000V, 300V UL so there may be different ratings for different certifications.

[jmaf]

it is M16878 / 1-BGE-6-COLOR
Here is the wire I bought.
I just needed a few feet, and I ordered it with other parts.
https://tubedepot.com/products/22-ga...ature-pvc-wire
T
** It appears to be this one, and it says it is 600v
MIL-W-16878/1 Type B Wire - Buy Online from Allied Wire & Cable, Distributor of MIL Spec Wire

@big_teee I'm not a wireologist to answer why precisely they label these wires as such, but I've used that exact same wire from Tubedepot for 500 VDC tucked right by the chassis no problems, no arc'ing.

[Justin Thomas]

A while back, years ago, I ordered some Teflon-coated 20ga from my local supplier. It was Belden, and when I was reading the label on the spool, it said, in short, that:

In open air, it was 600V. The amount of air gap needed was pretty tiny. It also said it was rated for 300V if submerged, and it was suitable for use in gasoline/transmission fluid/etc. So I could use it in my transmission...

I drew the conclusion that it was a combination of the insulation AND the surrounding medium. That said, I've used it at up to 500V in my 4 builds and had no arcs, shorts, or other problems. I haven't built an amp with an oil-cooled envelope and a plate cap, yet, though... >:O

Justin

[trobbins]

Unless you can get a link to a proper specification for that exact wire then you will just have to live with the confidence that it should be fine for your application. The plate wiring in output stages is more onerous than B+, and in general any such wiring should be kept clear of other wiring.

It is probably marked 300V for the main application - that could be a military compliance - and so could be very different from a commercial rating. It has no covering, so should only be used within equipment where it is protected. Some insulation materials offer better resistance to mechanical stress or nicking or oil or low smoke or comply to different flame extension performance or ..... the list goes on.

Some standards require a minimum thickness of insulation, or a need for a sheath covering, such as for mains AC use, and so although the voltage rating is ok, the wire may not pass other compliance hurdles.

Modern insulation thicknesses can get fairly thin, so be careful not to nick the insulation.

[big_teee]

I'll try this wire next time.
Hook Up Wire, 20 AWG, 600V-PVC, Red - Remington Industries
This is where I buy my pickup magnet wire.
Their wire has 600v marked on it.
I've used their 28ga 300v hookup wire and liked it.
T

**BTW, I don't think much of TubeDepot's Customer Service.
They misrepresent the rating, by saying on the website that it is 600v, and it is clearly marked 300v.
They refused my offer to send it back for a refund.
I don't like the idea of running 450v on wire that says 300v.
Seems like a huge liability issue to me.
As stated the insulation is only .010" PVC, and IMO is too thin for HT type voltages.

[big_teee]

I received a phone call from Tubedepot support rep manager.
He said that the wire says 300v twice on the wire, then says 600v at the end of the text string.
I told him I wasn't going to use wire with .010" PVC insulation, with 300v all over it for High voltage application.
He agreed to give me a refund for the wire.
After Our phone call, I took the wire and a magnifying glass, and looked for 600v on text string.
I never found it.
So for my build, I'm going to order some of the Remington Industries 600v rated wire.
It has .030" insulation, which greatly increases my HV confidence zone!
I told the rep, that with him calling me back, and giving the refund, his rating just went from very low to high.
T