Delete

[WSea]

They did state that if they upgraded the main panel they would have to get permits and have the electrical company come and cut stuff off at the road.

Should be able to pull meter

Sponsored

 

[Cosmacelf]

Should be able to pull meter

I don’t think so. I believe the entire combo meter panel must be replaced, which does mean cutting off power at road.

 

[WSea]

I don’t think so. I believe the entire combo meter panel must be replaced, which does mean cutting off power at road.

You’re right. Didn’t catch it was combo. Never understood why people choose those

 

[WSea]

Do these 250amp combo panels exist??? I can't find anything other than 200amp and 400amp.​

200, 320 or 400. 320s are pricey. Better to go with 2 200s. First you should get the load center properly sized

 

[ebellinder2]

Nice plan. To restate what has been stated so far the electrical code is designed to prevent overheating and fires. It is very important to recognize following the electrical code is a BARE MINIMUM I always exceed when possible wire size and circuit capacities

That said a new multi circuit panel is an excellent plan. You will be investing some significant dollars but you’re were very close to an electrical fire with what you had in place a day ago with the hot improperly added buss connection. Glad it has been temporarily rectified

So yes I also agree you should be able to handle an EV wall connector with a 48 amp load. The reason we all were so concerned was one for your personal safety and two when you add an EV you add something most systems have never dealt with that being a continuous 48amp load for 3-6 hours possibly daily which if not properly sized and installed can cause significant circuit heating and a resulting fire

Nice job following thru!!

Just for the record I have had my commercial electrical license for 38 years and anyone that skirts the NEC is playing with fire -literally

Good luck with your new very qualified electrician and your EV’s!!

 

[WSea]

Thanks all I'm very grateful for the advice! I'm admittedly unsure about a few things...

1. So if I have 4/0 wire going underground to my main breaker from the road, then unless I have that 4/0 replaced, I can only go with 250-amps. If I want 400amps, I'd need to have the 4/0 wire replaced with 400-kcmil Copper Wire or 600-kcmil Aluminum Wire?

2. There's no such thing as a 250-amp main combo breaker box? If so, does that mean I'd have to use a 200-amp box and lose the extra 50-amps available or purchase an expensive 400-amp box that can handle 250-amp but not be able to utilize 400-amps unless a new 600-kcmil wire is pulled?

3. How would (2) 200amp tandem boxes work? Wouldn't I need two wires coming from the road, or do I have to daisy chain them? Isn't that what was overloading that busbar to begin with?


If this helps, these are the house details.

5500sqft
(2) wall mount inverter heaters
radiant floors
indirect hot water tank connected to the boiler
gas stove
double electric ovens
hot tub
electric dryer

Size your load center.
ResidentialLoadCalculations.xls (live.com)

 

[Cosmacelf]

Thanks all I'm very grateful for the advice! I'm admittedly unsure about a few things...

1. So if I have 4/0 wire going underground to my main breaker from the road, then unless I have that 4/0 replaced, I can only go with 250-amps. If I want 400amps, I'd need to have the 4/0 wire replaced with 400-kcmil Copper Wire or 600-kcmil Aluminum Wire?

You want to avoid this if at all possible (and I think it is possible, see below). It is costly and it isn't sure that your conduit would support thicker wires.

2. There's no such thing as a 250-amp main combo breaker box?

But they do make 225A combo boxes. Click here to see the Eaton catalog pages (they make a 225A combo 20/40). And that should work fine for you.

Let's look at your big electrical consumers:

(2) wall mount inverter heaters - How many amps each are these? Let be conservative and say 40A each. So both would pull 60A together (breakers are always sized bigger than the load)
double electric ovens - 40A, pulls 30A
hot tub - 50A, pulls 40A
electric dryer - 30A, pulls 25A

So total you have 155A of load plus other incidentals if everything were turned on full blast. Which never happens. I would be comfortable with a 225A panel myself and adding the 60A charger (pulls 48A). And I don't think those inverter heaters are that big (let me know).

 

[Cosmacelf]

And by the way, two 200A panels doesn't work. At some point in the chain, you need a breaker that protects the total load of the wires coming from the meter. In practice, that means a 225A breaker is needed somewhere along the way, so see my above post.

 

[Cosmacelf]

This is the inverter heaters…

Awesome. So they draw a max. of 12A each. That's how you do a proper load calc, by the way, you look at the appliance's sticker to see the true maximum amperage draw. Anyways, now your household load calc has this:

(2) wall mount inverter heaters - 12A each, for 24A total.
double electric ovens - 40A, pulls 30A
hot tub - 50A, pulls 40A
electric dryer - 30A, pulls 25A

So that's 119A of major appliances, plus 48A new EV charger = 167A. That leaves you 116A of 120V power for all your 120V electrical stuff assuming a 225A panel. That really should be plenty. And when doing a load calc spreadsheet, everything gets de-rated since not everything is on at the same time (including the 240V appliances).

 

[ebellinder2]

So the inverters only pull 12 amps and they would not normally run 100% of the time together. Your electrician can quickly run a calculation using the many online worksheets that assign lighting and outlet amperage loads based on house sq footage and then you
add any special large loads such as inverters , dryer, hot tub and EV. I would be surprised if you will need more than a 200 amp service. A 400 amp service is pretty costly as many utility’s will charge you for new service cables to the house and possibly a new transformer as well. Out here that can easily be in excess of $10k

again I would be surprised if you will need more than 200 amp service. I have a 200 amp service in my 2300 sq ft home and the only time it works hard is when my EV’s are charging. Both car and truck will pull 90 amps continuous when they are both charging together but even then plenty of capacity left to run 4ton AC and other loads. I would start with the load calculation and see what you’ll really need before you spend a lot of money needlessly

just cleaning up the wiring on your home as discussed the last few days and modernizing with a newer load center ( breaker panel) may be all that is required

 

[ebellinder2]

Well you do have some unusual loads. If you can keep doing what you are doing and grab the nameplate data for your new electrician and then let him/her run the numbers we will soon be able to tell if your current electrical service is sufficient or if an upgrade to a 400 service is warranted. Just gather data on every circuit you have and the electrician will do the rest.

Sponsored