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Question On Panel Calcs For A New Service

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Old 01-26-2018, 04:15 PM   #1
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Question On Panel Calcs For A New Service

Here is what is going on:

A large house was converted to 3 Condos back in 2004. 3 new panels, 3 new meters. One of the panels has two sub-panels.

So the largest main panel for one of the condos has all the common area circuits on it. We installed a 4th main service so that we could separate out the common circuits (total of 50 amps) from the condo circuits (1 - 50amp breaker that goes to the sub-panel)

So what you now have are: 3 - Main panels with each with a 50amp service disconnect breaker, and, 1 New main panel which has a 125amp service disconnect breaker. So, simply adding everything up, you have a potential max load of 275amps.

The new panel has the 125amp disconnect, 100amp breaker to the sub panel (remember it used to be 50amps, don't worry, we installed the correct gauge wiring to handle 100amps to the sub). And a 220vac 50amp DPDT breaker for an outlet in the garage.

To take care of all this, and, the real potential of Condo owners wanting to increase loads on their panels (ie: max them out or replace them), we install a gutter box, 2.5inch gal conduit and 300kcmil THHN cabling to handle the new loads and possible future loads. NO problem.

Here is the problem. The POCO will not install a new meter for the new service. The rep came out and had a major cow. He said, the feeders from the transformer are only 100amps. Which for right now is fine, because we have not yet increased the load---no meter to the new panel. But, the real question is: How come the POCO did not replace the lines back in 2004 when the new panels and meters went in, and, the load increased from 50amps (old panel) to 175amps (3 new panels)?

Now the POCO wants calcs on the new panel. Frankly, it's a 125amp panel, 125amp disconnect. The only things really added to the new panel is the 50amp breaker for the garage, and, a 100amp breaker for the sub. The other panels are all existing, permits pulled, inspections and so forth back in 2004. If you are looking for Max Load, it's 150amps tops, but that is limited by the 125amp disconnect.

Frankly, I don't see a need to go through all the circuits and appliances for the existing subpanel --we didn't add anything, there is no additional load at the sub. The 70amp main disconnect on the old panel never tripped and it was supplying the existing sub. We simply upped the amps to the sub with new wiring and a 100amp breaker.

So, anyone here see problem with this?? What did I miss ?

BTW, when we do put in a new main service, I go through all the calcs on circuits on that panel. We use an excel sheet for this that has macros that calculate it all out.
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Old 01-26-2018, 09:01 PM   #2
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Re: Question On Panel Calcs For A New Service

POCO blew it when they didn't upgrade the feeder in 2004.

Almost had that happen here on one, but the electrician caught it and made them upgrade.


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Old 01-26-2018, 09:28 PM   #3
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Re: Question On Panel Calcs For A New Service

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Old 01-28-2018, 06:13 AM   #4
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Re: Question On Panel Calcs For A New Service

POCO is an in an Uber Regulated industry (monopoly Utility) in a what most consider a really large mental facility sans fences known as the State of California.

Said POCO wants to make $, it will max every opportunity to extract money from their customers for equipment required by regulation if not actual need......

Put the main in the garage and feed the legacy panels off it?

Fight back and remove 2 of 3 three POCO meters, install owner owned meters(4, three codos, one commons?) to resell power at cost, ELIMINATING forever the monthly meter charges for 2 services.... Only about 11.00$ a month/ meter?

Add solar panels for a "free" upgrade?

As an aside, at 25 cents a KiloWatt, anyone with a large heated pool should look at a natural gas powered co-generation plant...

Double aside: Isn't all the E-star baloney & LED lighting etc... cutting actual "normal" KiloWatt usages across all residences? Sans Mini-mansions....
I might be an Idiot, but I know things that You don't: Please wait till after you get my know-how to insult me....

Last edited by Fouthgeneration; 01-28-2018 at 06:21 AM.
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