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#217072 - 04/22/16 06:42 PM Table 39
brsele Offline

Registered: 07/29/08
Posts: 88
Loc: Northern Ontario
So Ontario is adopting the new code starting May 1st.
As I believe most of you have been working with the new code for a year now, I have a question with regards to the new table 39.

As per 8-104(6)(a), when would somebody put an 89A calculated load on a 100A service?

Or is somebody manufacturing main breakers now rated for 100%

Thanks... Bruce

2014 / 2011 NEC & Related Books and Study Guides
#217073 - 04/23/16 02:35 PM Re: Table 39 [Re: brsele]
twh Offline

Registered: 03/11/04
Posts: 895
Loc: Regina, Sask.
8-200(3) says calculated loads for residential services are not continuous.

#217074 - 04/23/16 06:03 PM Re: Table 39 [Re: brsele]
brsele Offline

Registered: 07/29/08
Posts: 88
Loc: Northern Ontario
Thanks TWH.
This question came to me as I've been asked to wire a new house being built with electric heat. A 100A service was specified.

This is the first time in my life I've been asked to supply a 100A service for a new house and electric baseboard heaters.

So I did a load calculation and came up with 85A.

I always thought that the max. calculated load for a 100A service was 80A and the max. for 200A was 160A.

I'm wondering if this is a case where I was originally taught wrong and never questioned it, or if something changed and I never noticed because everybody asks for a 200A service.


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