200a ATS vs 150a service

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LarryFine said:
Am I also correct that load shedding is necessary? In my pic, I see the following circuits that it applies to:

Heat
A/C
Water heater
Range

Am I correct that load shedding is only required for loads that would cause overloading? For example, if the A/C, heat and, range are disabled, the water heater may remain connected without load calculations?
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Shouldn't 24 kW be able to handle the whole load? You aren't likely to run Heat and A/C at the same time.
 
gadfly56 said:
Shouldn't 24 kW be able to handle the whole load? You aren't likely to run Heat and A/C at the same time.
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Agreed in general; I'm hoping to not have to do a load calc for the permit. A dryer won't restart, but a water heater will, and there are two 60a breakers, even though only one is labeled heat.

The pic is a bit blurry, but the 2-poles are: Dryer 30; Water heater 30; Heat 60 (or 50); Unlabeled 60; Range 50 (or 60!). There is also a Homeline breaker. If I get the job, I will check everything.

The customer told me (and it's obvious) is is not the original service; I'm guessing it was an illegal upgrade. Too bad it wasn't done correctly the first time. That might have saved me some time.


I would like a couple of opinions on price. I'm at an even $2K right now, not including the permit and attending inspection(s), removing the existing transfer switch, or any wall patching to be done.

I will need to supply the new service cabling, generator feeder and control wiring, re-route the grounding electrodes to the ATS, separating grounds and neutrals, and of course, the rest of the labor.
 
In asking for price opinions, I should add that I am allowing a full two days in all.

I added charges for permit and inspection, and for removing the old T/S and wall patching.
 
LarryFine said:
Agreed in general; I'm hoping to not have to do a load calc for the permit. A dryer won't restart, but a water heater will, and there are two 60a breakers, even though only one is labeled heat.

The pic is a bit blurry, but the 2-poles are: Dryer 30; Water heater 30; Heat 60 (or 50); Unlabeled 60; Range 50 (or 60!). There is also a Homeline breaker. If I get the job, I will check everything.

The customer told me (and it's obvious) is is not the original service; I'm guessing it was an illegal upgrade. Too bad it wasn't done correctly the first time. That might have saved me some time.


I would like a couple of opinions on price. I'm at an even $2K right now, not including the permit and attending inspection(s), removing the existing transfer switch, or any wall patching to be done.

I will need to supply the new service cabling, generator feeder and control wiring, re-route the grounding electrodes to the ATS, separating grounds and neutrals, and of course, the rest of the labor.
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If you do need to load shed, most higher end ATS's have relay packages that allow you to stage the fall-over for large loads, so you're not trying to start the A/C compressor, range, and well pump at the exact same time. I think they even have a re-try feature that will give a particular load a few go's before staying locked out. They are available in some cases as field kits.
 
gadfly56 said:
If you do need to load shed, most higher end ATS's have relay packages that allow you to stage the fall-over for large loads, so you're not trying to start the A/C compressor, range, and well pump at the exact same time. I think they even have a re-try feature that will give a particular load a few go's before staying locked out. They are available in some cases as field kits.
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Yes, this ATS does include modules. I merely mean I will probably have to do some LV wiring for the HVAC.
 
LarryFine said:
I would like a couple of opinions on price. I'm at an even $2K right now, not including the permit and attending inspection(s), removing the existing transfer switch, or any wall patching to be done.
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my theory is that if customer will agree to $2,000, he'd probably agree to $2,250

and vice versa
 
LarryFine said:
In asking for price opinions, I should add that I am allowing a full two days in all.

I added charges for permit and inspection, and for removing the old T/S and wall patching.
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I have done a bunch of those over the years, but none very recently where I remember how much time it took. What are you thinking like $500 in materials? I would probably figure more than 2 days. Always seems like it takes nearly half a day to seperate N-G in a packed messy panel.....Going to need a new riser, wx head, meter makeup, maybe a meter while you are at it......I often find the existing electrodes are garbage or not compliant. A decent amount of time. Id throw on at least an extra half day. Do you have to mess with moving/setting the genny or is that in place already?
 
electrofelon said:
What are you thinking like $500 in materials? I would probably figure more than 2 days. Always seems like it takes nearly half a day to seperate N-G in a packed messy panel.....Going to need a new riser, wx head, meter makeup, maybe a meter while you are at it......I often find the existing electrodes are garbage or not compliant. A decent amount of time. Id throw on at least an extra half day. Do you have to mess with moving/setting the genny or is that in place already?
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I figured materials at about half of that, and about two hours at the panel. I'll straighten it out while there is no feeder cable in it. I'm a quick worker when I don't have to walk around.

The meter base is already 200a, and the POCO is responsible for the meter and everything on the line side here. The genny will be delivered and set roughly in place by the shippers.

I should be able to get the power back on on in one day, but I will suggest the customer arrange a place to stay overnight just in case I don't. The second day should be the generator.
 
Well, I got the job!

Quick question: The 22kw generator comes with a 100a breaker. As a feeder, is #2 aluminum SER large enough?
 
LarryFine said:
Well, I got the job!

Quick question: The 22kw generator comes with a 100a breaker. As a feeder, is #2 aluminum SER large enough?
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Most inspectors here will allow that if it is for a dwelling. I've heard the argument that the genny is not supplying the entire load and you have to use the ampacity tables, which would call for a #1 Al.
My stance is, the genny is supplying all the load that is connected to it. You won't pull more than 100A and if #2 is good enough for a dwelling 100A service it should be enough for a 100A genny.
 
If my understanding is correct the wire in question is the feed from the gen to the service rated ATS. The protection of that wire is found within the gen, at that 100A breaker, therefore size would be determined by protection not maximum system load as it would the mbp, as no current is within that wire unless gen is operating. Wire between utility - ATS - main panel would be sized using the normal process. ATS sized by service rating as full load goes thru between utility and main panel.
Load shedding is not for protection of the circuits or the transfer but to prevent overloading of the gen, and incidental shut down, or worse, of your backup power. Generac makes a load shed that doesn't require any low voltage connections to the transfer, it connects in line to the circuit in question and continuously monitors utility frequency to be ready to shed loads when gen starts and is operating, it is programmable to allow total shed of load or monitored shedding that would allow normal operation if other loads in combination dont cause overload. They now offer shedding units of up to 50A or (100A if you desire to shed loads to a subpanel). PSP Products also makes load shedding that functions similarly, but can be customized to shed multiple circuits in one enclosure. In your case this would fit in the space vacated by the old transfer.
 
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