Guess the gauge?

[Peter Wigle]

I'm trying to identify the service size. The wire gauge identification has been painted-over but I am holding a sample length of 3 AWG conductor almost right next to the service conductors.

The main breaker was 100 amp but I think the service conductors look too thin. Is it possible to make that determination by comparing the diameter of the actual conductors to that of a sample whose gauge is known?

[Jerry Peck]

Sometimes sorta possible, however ...

Unless that sample is way out of perspective length to diameter, that drip loop is either real low (less than 10 feet minimum above where you are standing) or you are real tall and can reach almost 10 feet from where you are standing.

I suspect you are not THAT tall.

Meaning that leaves the service drop way too low.

In which case the size of it does not matter, it needs to be changed anyway. :)

[Peter Wigle]

Thought you might mention that one, Jerry. I'm standing on a flat roof (second storeyporch) and that lack of clearance is also in the report.

[Jerry Peck]

Thought you might mention that one, Jerry. I'm standing on a flat roof (second storeyporch) and that lack of clearance is also in the report.

If you are on a flat roof, not subject to normal pedestrian traffic (i.e., not a deck surface, but a porch roof itself), then the clearance only needs to be 8 feet.

Was it 8 feet high above the roof?

If not, it all needs to be replaced anyway.

If yes, and you are actually basically almost touching the service entrances conductors, they do look smaller. It "could be" a 4 AWG, which is rated for 100 amps, it "could be" a 6 AWG which is too small (they don't make a 5 AWG, so it is either a 4 or a 6).

I wish you had held it in alignment with the other conductor so there was an accurate comparison.

If the height is too low, your problem is solved: Replace service entrance conductors and mast to provide proper clearance over roof, make sure the service entrance conductors are properly sized, recommend installing larger service entrance conductors to allow for future upgrade of electrical service and panels.

[Peter Wigle]

The loop is less than 8' (close to 7-1/2'). The sample I'm holding is less than two inches closer to the camera than the service conductors are. It still affects perspective, but those conductors were a lot thinner than my sample.

Thanks for your info.

[Jerry Peck]

The loop is less than 8' (close to 7-1/2').

That means they might be able to tighten up a bit on the drip loop, still leaving a drip loop and still make 8 feet - maybe.


The sample I'm holding is less than two inches closer to the camera than the service conductors are. It still affects perspective,

That 2 inches affects perspective A LOT.

With that 2" away, I'd have to say *it might* be 4 AWG ... *might be* ... and if it is then it is rated for 100 amps.

Right it up as I said before, and if the electrician successfully shortens the drip loop, YOU STILL told them to verify the size of the service entrance is large enough and YOU STILL told them you recommend installing larger service entrance conductors for future upgrades of the service or panel.

[Fred Warner]

Jerry, I agree. Not only the service conductors but also the service drop conductors. This means, as you say, the splices and the bottoms of the drip loops have to maintain a vertical height of not less than 8 feet.
Some electricians around here believe the point of attachment needs to be 8 feet or higher and they readily allow the drip loops to encroach the limits set by code and power company regulations. :)

[John Kogel]

If you are on a flat roof, not subject to normal pedestrian traffic (i.e., not a deck surface, but a porch roof itself), then the clearance only needs to be 8 feet.I reluctantly must point out :) that in Canada that min measurement is 2.5 Meters, or 8.2 feet. No I cannot cut and paste the code, I do not have the CD and I am not an electrician.

[Jerry Peck]

I reluctantly must point out :) that in Canada that min measurement is 2.5 Meters, or 8.2 feet.


Then they lose several critical inches of available height.

I pointed out the service entrance conductors as they were lower than the overhead service drop conductors, Fred pointed out the overhead service drop conductors TOO, and with that minimum height now being slightly higher, the overhead service drop conductor will also come into play.

From the apparent height above the bottom of the drip loop, there MIGHT be enough length to raise the bottom of the drip loop by about 9 inches, which is about what you are talking about from 7-1/2 feet to 8.2 feet.

However, what is also now going to come into play is the height of the anchor point for the overhead service drop conductors, that may also have to be raised.

All of which leads to a greater likelihood that the service may have to be reconfigured to attain a greater height above that flat roof.

[John Kogel]

Then they lose several critical inches of available height.

I pointed out the service entrance conductors as they were lower than the overhead service drop conductors, Fred pointed out the overhead service drop conductors TOO, and with that minimum height now being slightly higher, the overhead service drop conductor will also come into play.

From the apparent height above the bottom of the drip loop, there MIGHT be enough length to raise the bottom of the drip loop by about 9 inches, which is about what you are talking about from 7-1/2 feet to 8.2 feet.
All of which leads to a greater likelihood that the service may have to be reconfigured to attain a greater height above that flat roof.
The local authorities have the power to approve a lower height (did it for me once) but I would not suggest trying that.
The danger is from zealots with snowshovels up on their flat roofs, flat roofs should be banned.:rolleyes:

[Jerry Peck]

The local authorities have the power to approve a lower height (did it for me once) so I would suggest trying that.

Why on earth would you *suggest trying that*?

Do you want them to have a greater opportunity to kill themselves?

NEVER *suggest* trying to get around a life safety code requirement.


The danger is from zealots with snowshovels up on their flat roofs, a practice which itself should be banned.:rolleyes:

And YOU *want* to *suggest* trying to allow them getting killed easier? :eek:

I can see it now:

Judge: Mr. Kogel, as the testimony states, you recommended they try to get a variance for the lower conductors, knowing the dangers, is that correct?

Mr. Kogel: (silence ... you certainly do not want to say "Yes your Honor.")

[Fred Warner]

Not only snow shovelers but children in the hot summer months who lay on the roof to get a suntan and carelessly drape their towels and clothing over the drop conductors.

[John Kogel]

Why on earth would you *suggest trying that*?

Do you want them to have a greater opportunity to kill themselves?

NEVER *suggest* trying to get around a life safety code requirement.



And YOU *want* to *suggest* trying to allow them getting killed easier? :eek:

I can see it now:

Judge: Mr. Kogel, as the testimony states, you recommended they try to get a variance for the lower conductors, knowing the dangers, is that correct?

Mr. Kogel: (silence ... you certainly do not want to say "Yes your Honor.")If the authority approves it, I'm safe. If he dissapproves it, they have to add a mast, I'm safe.

It may have been approved when it was built.
It's not uncommon to see wires a few inches low.

But you are right, I would not suggest it. :)

[John Dirks Jr]

First, to me it looks like the sample in your hand is closer to the camera. If it is, it will look bigger in the picture.

Second, what about the thickness of the insulation on the conductor? It can vary from era and manufacturer.

It's a shot in the dark to judge the conductor this way.

[John Steinke]

Good heavens! Looks like it's time for a services 'primer.'

First, check your local utility's standards. That mast, weatherhead, and the wires are almost certainly sized for the older 60 amp service. If the meter is sitting on a round can, it is also rated 60 amps.

I suspect a 'service change' was done without a permit. When you upgrade a service, you replace all that stuff - not just change the breaker box.

I would also be surprised to find a ground rod. Yes, one is needed.

[Mark Bilyeu]

Good heavens! Looks like it's time for a services 'primer.'

First, check your local utility's standards. That mast, weatherhead, and the wires are almost certainly sized for the older 60 amp service. If the meter is sitting on a round can, it is also rated 60 amps.

I suspect a 'service change' was done without a permit. When you upgrade a service, you replace all that stuff - not just change the breaker box.

I would also be surprised to find a ground rod. Yes, one is needed.

Actually two are needed.

[Byron Lentz]

My guess is #4, which is what is usually used for a 100 amp service. The next time, you might want to check at where the wire enters the braker, you may get a better look at it then.

[Bill Kriegh]

One of the problems with guessing about the size of an old service like this is that the type of insulation on the wire can make the difference in the rating. Types TW and THW are common for old service wire. If the wire size is #4 and the type is TW it is OK for a 60 AMP service while if type THW it would be OK for a 100 AMP. So, in this case a #4 wire at the meter won't necessarily tell you whether you have a 60 AMP or 100 AMP service.

A round meter housing the same diameter as the meter is going to be a 60 AMP but anything larger gets you into guessing again.

Given the age of the materials and the size of the wire versus the Insulinks in the picture I'd GUESS the wire is #4. But not knowing the insulation type this doesn't help a bit.

[Jerry Peck]

If the authority approves it, I'm safe.


Quite to the contrary.

Just because the authority approves it does not make it safe, and because *you* recommend they contact the authorities to approve it means *you* felt it was safe, so you are still on the defendants list and quite possibly the first or second name on that list.


It may have been approved when it was built.
It's not uncommon to see wires a few inches low.

Right, because they were built wrong, which is what keeps you in business. :D

[Paul Johnston]

It is very disturbing that these things get past the POCO and electrical inspectors that sign off on the work and then it is discovered years later. The local municipality should have to pay the cost of repairs because you pay them a fee. I know that is not the real world (should be) just thinking out loud.

[brian schmitt]

Actually two are needed.
mark,
got a code section?

[John Kogel]

I'm trying to identify the service size. The wire gauge identification has been painted-over but I am holding a sample length of 3 AWG conductor almost right next to the service conductors.

The main breaker was 100 amp but I think the service conductors look too thin. Is it possible to make that determination by comparing the diameter of the actual conductors to that of a sample whose gauge is known?
Here we go agin, :) the poster is in Ontario, Canada. For 100 amp service, a #3 Cu conductor (or a #2 Al) is required.

Peter, if you can see the cut end to determine if it is Copper, then you can compare a sample like you show in the pic. Just be aware that the insulation can be different thicknesses as pointed out above, and the main thing, it could be Al.

Below is a pic of Copper #3, 100 Amp service. Notice the wires are the same diameter as some of those trees.:)

[Bill Kriegh]

For 100 amp service, a #3 Cu conductor (or a #2 Al) is required.

Yeah, but when this service was built wasn't #4 American = to like a #3 Canuck? (sorry, couldn't resist)

[John Kogel]

For 100 amp service, a #3 Cu conductor (or a #2 Al) is required.

Yeah, but when this service was built wasn't #4 American = to like a #3 Canuck? (sorry, couldn't resist)Funny thing is, we use the American Wire Guage, AWG. But like our football fields, we like BIGger.