How to tell wire size without it being labelled?

[Jim Johnstone]

Hey Sparky's,

I have just bought a house with a detached garage, that is connected to my main panel with what looks to be #2 aluminum wire, but the sheath has no markings. How can I confirm this?

Thanks,
Jim

 

[Grumpy365]

Hey Sparky's,

I have just bought a house with a detached garage, that is connected to my main panel with what looks to be #2 aluminum wire, but the sheath has no markings. How can I confirm this?

Thanks,
Jim

If there is no markings, don't use it. ( scrap it).

There are too many variable in wire ratings ( design temp, insulation type, rated location, etc.)

Sorry dude.

 

[Jim Johnstone]

The only downside to that, is it's already buried under a paved driveway, already hooked up to the breaker panel in the house, and fuse box in the garage, and has been for 20 years. I can only see 4 or 5 inches of sheath in the fuse box and unfortunetly no markings on those few inches.

It's on a 40 amp breaker now, and I'm just looking to confirm size before I up it to a 60 amp.

Would an electrician be able to ID it visually?

 

[Grinder Bill]

Google is your friend

http://en.wikipedia.org/wiki/American_wire_gauge

 

[nehog]

Cut off the power (all of it).

Measure the diameter of the wire if single solid conductor... There are many charts to tell you the AWG of the wire. If it is stranded, you can measure the size of one strand, then count the number of strands to determine the true AWG (again, using a table...)

We do this all the time with AWM that we suspect is mis-marked or is not properly marked.

 

[Aceman]

If there is no markings, don't use it. ( scrap it).

There are too many variable in wire ratings ( design temp, insulation type, rated location, etc.)

Sorry dude.

Good grief!

Why in the world would anyone want to scrap wire that's in use just because they can't read the insulation type??



Do you know how many times I've come across old wiring I can't read markings on? A lot. It's been working fine for years, but you think I should start telling customers I need to replace it because the markings have since been worn off?

 

[Jim Johnstone]

Cut off the power (all of it).

Measure the diameter of the wire if single solid conductor... There are many charts to tell you the AWG of the wire. If it is stranded, you can measure the size of one strand, then count the number of strands to determine the true AWG (again, using a table...)

We do this all the time with AWM that we suspect is mis-marked or is not properly marked.

Awesome, thanks. It's stranded aluminum, I am upgrading the old screw type fuses to a breaker panel anyway, so I will be pulling it all apart within the next few weeks. I'll measure it up then.

Cheers,
Jim

 

[Grumpy365]

Good grief!

Why in the world would anyone want to scrap wire that's in use just because they can't read the insulation type??



Do you know how many times I've come across old wiring I can't read markings on? A lot. It's been working fine for years, but you think I should start telling customers I need to replace it because the markings have since been worn off?

Because I misinterpreted the first post and thought he had random Al (atomic #13) wire he wanted to use.
(I apparently **** at reading comprehension today)

If he had random unmarked Al wire laying around, Not knowing if it is direct burial, temp rating, etc. I would scrap it.

If it was already installed, I'd use it and never think twice about it.

 

[johno]

If you disconnect the wire from the terminal in the box, you need to recoat that wire before you reinstall in terminal. It prevents oxidation and high resistance, pretty important.

Can't remember the name of the stuff, I'm sure someone here will tho.

 

[Alchymist]

If you disconnect the wire from the terminal in the box, you need to recoat that wire before you reinstall in terminal. It prevents oxidation and high resistance, pretty important.

Can't remember the name of the stuff, I'm sure someone here will tho.

http://www.amazon.com/dp/B0019KHHRE/?tag=atomicindus08-20
Might be cheaper other places.

 

[Jim Johnstone]

If you disconnect the wire from the terminal in the box, you need to recoat that wire before you reinstall in terminal. It prevents oxidation and high resistance, pretty important.

Can't remember the name of the stuff, I'm sure someone here will tho.

Good advice, I had already had a look at Home Depot for anti Ox stuff, lots of options out there.