Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: daveyajd on March 17, 2012, 08:25:21 pm

Title: Using Doug's 22ga cloth wire for higher voltage connections
Post by: daveyajd on March 17, 2012, 08:25:21 pm

Can it handle it? I am trying to use this in any place I can as I rewire. I know I can use it for the signal connections but are there places I should use heavier gauge?

Title: Re: Using Doug's 22 ga cloth wire for higher voltage connections
Post by: Willabe on March 17, 2012, 09:08:34 pm

It's the current and the voltage rating of the wire and insulation that you need to know if you can use it for any given use.

Title: Re: Using Doug's 22ga cloth wire for higher voltage connections
Post by: stingray_65 on March 17, 2012, 09:37:09 pm

ok,

Let's get a few terms here straight because it is important to be on the same page on these subjects. These are Voltage Rating and Current Rating.

In the subject line you ask about voltage, the gauge of the wire has nothing to do with it's voltage rating. The insulation does.

In your original post you ask if there are places you should use a heavier gauge, this is a question that refers to current ratings. This is where the gauge of a wire matters.

SO, to answer the posted question if there are places you should use a heavier gauge in places, YES.

The areas are few, the mains. all of your mains everywhere should be 16ga or more.
Heaters, the preferred way is to wire the heater wires (6.3v) from the PT to either a lug strip or the lamp. from there, use 18ga to the power tubes. from the power tubes to the preamps you can safely use 20 or 22ga.
Rectifier heaters, (5v) should have a direct connection from the PT or if landed on a lug strip for what ever reason, should be wired with 16ga.

NOW as far as voltage ratings, I believe the cloth covered wire Doug sells is rated at 300V. I may be wrong, Doug will have to verify that himself. However, Many of us, including myself, have used it at much higher voltages with no ill effects.

Title: Re: Using Doug's 22ga cloth wire for higher voltage connections
Post by: daveyajd on March 17, 2012, 10:21:54 pm

Thank you Stingray. I understand the use of heavier gauge on the heaters. If I understand the rest of it then I can safely use it for component connections. (270v) If Doug will verify the insulation rating that would be great.

Title: Re: Using Doug's 22ga cloth wire for higher voltage connections
Post by: bigsbybender on March 18, 2012, 03:07:45 am

I've used this wire for plate supplies at ~525 volts, No issues after several years.

Insulation is fairly conservatively rated.  It is rated assuming that either 1. It's in a bundle of several wires and 2. There isn't a protective chassis.

j.

Title: Re: Using Doug's 22ga cloth wire for higher voltage connections
Post by: EL34 on March 18, 2012, 07:03:33 am

What does it say at the top of my wire page where you purchased the wire?

http://www.hoffmanamps.com/MyStore/catalog/parts18.htm (http://www.hoffmanamps.com/MyStore/catalog/parts18.htm)

Title: Re: Using Doug's 22ga cloth wire for higher voltage connections
Post by: Boots Deville on March 18, 2012, 07:53:15 am

To be fair to the OP, Doug, your comment at the top of the page references the PVC coated wire, and he's asking about the cloth jacket wire.

Title: Re: Using Doug's 22ga cloth wire for higher voltage connections
Post by: EL34 on March 19, 2012, 06:35:51 am

Ok, sorry, did not see the cloth word
I don't have a rating on the cloth wire

I would use it it every place it is used in old amps which is just about everywhere except heaters

I have seen cloth wire laying in a pool of goo inside old amps and still not short out to the chassis