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Discussion Starter · #1 ·
So the typical Reliance transfer switch panel (i.e. http://www.reliancecontrols.com/ProductDetail.aspx?51410C) has 15 or 20 amp circuit breakers that feed double throw switches. But now that AFCI protection is required on pretty much every residential circuit -- and there's no exception to allow for non-AFCI when building loads are on generator power -- the only way these circuits meet Code is if the first device is AFCI protected, right? Even if there's an AFCI breaker in the main panel protecting the load 99% of the time?

I wonder how this will affect sales, or whether inspectors will even flag something like this?

I have one of these ready to install in my home, but now I'm considering just bringing it back and getting a 60A double throw switch that feeds a sub-panel with AFCI breakers...
 

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So the typical Reliance transfer switch panel (i.e. http://www.reliancecontrols.com/ProductDetail.aspx?51410C) has 15 or 20 amp circuit breakers that feed double throw switches. But now that AFCI protection is required on pretty much every residential circuit -- and there's no exception to allow for non-AFCI when building loads are on generator power -- the only way these circuits meet Code is if the first device is AFCI protected, right? Even if there's an AFCI breaker in the main panel protecting the load 99% of the time?

I wonder how this will affect sales, or whether inspectors will even flag something like this?

I have one of these ready to install in my home, but now I'm considering just bringing it back and getting a 60A double throw switch that feeds a sub-panel with AFCI breakers...
I guess Reliance can either produce afci T switches, or buy an ex. from CMP-2

~CS~
 

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Discussion Starter · #7 ·
Just an interlock kit on the main breaker. Backfeed the whole house.
I thought about that, and the flexibility it would afford, but am worried about the next potential homeowner being an idiot and either removing the plate and paralleling to utility, or overloading the generator. Or both.

But maybe that's just paranoia on my part. I was thinking an MTS and sub-panel would be pretty idiot-proof. Or maybe just not worry so much about the whole AFCI while on generator deal.

I do tend to overthink things.
 

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I thought about that, and the flexibility it would afford, but am worried about the next potential homeowner being an idiot and either removing the plate and paralleling to utility, or overloading the generator. Or both.

But maybe that's just paranoia on my part. I was thinking an MTS and sub-panel would be pretty idiot-proof. Or maybe just not worry so much about the whole AFCI while on generator deal.

I do tend to overthink things.
.....or using a Generac portable generator which all models now have a bonded neutral
 

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Discussion Starter · #10 ·
My main panel is a 225A Eaton CH, and my portable generator is a 10kW Duromax that will have a 50A, 240V cord connected to a 50A exterior inlet.

The sub-panel I was thinking of that would accept CH AFCI’s was this:

http://www.homedepot.com/p/Eaton-12...-CH12L125R/100158480?N=5yc1vZbm2wZ384Z1z0x9jl

And for an upstream double throw switch I was thinking of this:

http://www.homedepot.com/p/Eaton-10...ty-Switch-DT223URH-N/100151733#specifications

The #8 AWG neutrals would all be tied together in the switch, as would be the equipment grounds (separately).

I was also thinking about getting some small wattmeters for the subpanel buses to make sure the legs stay balanced.

It's been awhile since I brushed up on Article 702, so let me know if I'm missing something.

 

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The watt meters are pretty much useless unless you are standing right there. Fire up the microwave and there goes your balance

Just balance the load the best you can when you transfer the circuits
 

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It doesn't matter what the load calc is, you can manipulate the load with a manual transfer switch and be compliant. Whether your customer can figure that out is for you to decide. Solve the bonded neutral issue with one of the xpanels. Most of the portables out there are bonded neutral and you will run into ones now that have a whole generator GFCI function that flat out won't work unless you lift the bond or use a neutral switched transfer switch. Generac has a label for their XP's which is fine as long as it doesn't end up at a construction site.
 

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Discussion Starter · #16 ·
You need to use an interlock and feed the whole house.

It's the best way to do it.
I don't disagree, but my panel is main lug only, with the 200A service disconnect breaker outside. I'm not even sure I can mount a 200A breaker in this MLO panel. But I am leaning toward putting in a sub-panel with interlocks now. Probably more expensive than the double throw switch combo but will save wall space.

I also found a wiring schematic of my generator, and it appears that the neutral and ground are not bonded, so that's good.
 

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I don't disagree, but my panel is main lug only, with the 200A service disconnect breaker outside. I'm not even sure I can mount a 200A breaker in this MLO panel. But I am leaning toward putting in a sub-panel with interlocks now. Probably more expensive than the double throw switch combo but will save wall space.

I also found a wiring schematic of my generator, and it appears that the neutral and ground are not bonded, so that's good.
So pop in a main breaker panel. Since you are an electrician it only costs you the price of the panel and a day. Then you can pop your double pole 50A breaker where it needs to go for the interlock, and be golden. You can buy a 40 circ panel and an interlock for less than a reliance 6 circuit transfer switch. No brainer, imo.
 
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