Electrical service rating

I inspected a house today where the current owner insists that the service to the house is 60 amps.

The service entrance conductors were copper #2AWG (which can support 125 amps in Canada I believe). The main fuses were rated at 100 amps so they are the limiting factor. Isn’t this a 100 amp service?

Is it possible that the wires from the service drop to the house are only rated to supply 60 amps, but the house has been wired from the drop to the box with wire that can provide 100 amps if the drop wires are updated?

Joe,
AS Jerry said, based on what you see, it should be 100 AMP. The fuses are the limiter. You cannot have a 100amp service on 60 Amp wire, hydro would have stopped that. Why would the owner claim it is lower anyway?

I compiled the following table from the Alberta Electrical Code.

Feel free to use it subject to comformation to your local codes.

David,

The weakest link is the limiter and not necessarily the fuses as I’ve seen 60 Amps conductors feeding a 100 Amps panel.

What Hydro doesn’t see, we should.

Cheers,

Marcel,
As Joe said, the main fee wires were #2 so they carry over the 100Amp (125 amp) The main conduit was 1&1/4 inch so it is okay.
You cannot install 100 Amp fuses in a 60Amp service. Joe mentioned this was the main setup.

What you may see is a #6 wire run out of the main panel to a sub-panel with a 100 Amp breaker or fuse on it. This should be corrected.

I cannot figure out why the seller insists this setup is 60AMP. Usually it is the other way around. They will try to insist there are 2 60AMP fuses, so they will tell you this means it is a 120AMP service.

David: The owner really didn’t know his heiny from a hole in the ground when it came to the electrical system.

The rest of the electrical in the house was pretty messed up with open grounds, reversed polarity, abandoned live wires, non-working and missing GFCI’s and non-functional circuits, but I’m pretty happy with my assessment of the panel.

The evidence was pretty obvious with the #2 AWG conductors feeding 100 amp fuses that it was in fact 100 amp service to the property. With all of the other issues, I warned that “several of the circuits appear to have been installed by a person that is not a licensed electrician. Repair or replacement by a licensed electrician is recommended.”

I’d like to thank all for their input on this issue. It is really quite a wonderous thing that this much discussion can be elicited with one simple question.

David,

I agree, in this situation service should be 100Amps. I was making a general comment to the fuses being the limiter.

You mention above that the main conduit was 1 1/4 inch and that wasn’t mention before; for example, a smaller conduit would have been a weak link.

Don’t you love it when the Realtor insists that the service is 200 Amps (100 + 100)…

Cheers,

Marcel,
I get the the 60 + 60 means it is a 120AMP

Or one I got a lot of grief over was from a listing agent (after the buyer walked, I also showed her it was only 5’6" off the ground and advised it be raised or run underground)

The agent stated "it is 35+35 which makes it a 70AMP service,
that stupid inspector is not an electrician and obviously does not have a license as an electrician or he would know better.You people should hire a real inspector and sure it is one who knows what he is talking about "
A week later we all found out the vendor had been advised by Hydro that the service was too low and the entry was not safe. He had a quote from an electrician that pointed out it was a 35AMP service and needed to be upgraded at a quote of $3200.

Someone then told the listing agent I was the inspector and had advised of the low entry as well.   She apologized to the buyers agent and to me and mentioned she had not been told I was the inspector.   She ripped a huge strip off her vendor.