[decomo]

Hi experts:
For my general understanding, I would like to understand what electricians refer to when discussing options for upgrading a 200 amp panel to a 400 amp panel and the wide range of price differences of the 400 amp panel. My situation is I have an older 200 amp panel that feeds 100 amp to a subpanel for a granny unit and I want to upgrade to 400 amp - the feed is above ground/overhead.

Assuming the space requirements by the panel(s) is not important, is there a difference in:
(option 1) getting one 400 amp panel with all the breaker spaces (e.g., 40) and
(option 2) getting one 400 amp panel with eight (8) spaces for higher amperage lines (e.g., 40, 50, 100 and 200 amps) and a 200 amp panel with 40 spaces to feed the remaining lines?

With option 1, the quotes I get range from $4500 to $7000. With option 2, the quote I get is about $4000. It seems the price of the 400 amp panel varies greatly between the two options - $2400 vs. $800). It also seems to me the prices of the individual breakers are the same between the two options.

Thanks.

 

[rjniles]

Most 400 amp residential services are actually 320 amps. Provisioned as 2 200 amp panels.

 

[decomo]

Can you please elaborate on how that work? Do they feed 400 Amp into the first 200 amp panel and then daisy chain 200 amp from the first to the second panel? or do they run two separate feeds one for each panel?

 

[AllanJ]

I do not know why the styles of 400 amp panels vary so much in price.

But with option 2 you might be able to have installed just the 400 amp panel with the 8 spaces and connect the existing 200 amp panel to one set of spaces. The success of this arrangement would depend on an empty space for the new 400 amp panel within reach (typically five feet) of where the new 400 amp service conductors enter the house.

 

[rjniles]

Can you please elaborate on how that work? Do they feed 400 Amp into the first 200 amp panel and then daisy chain 200 amp from the first to the second panel? or do they run two separate feeds one for each panel?

The service has separate feed from the meter to each 200 amp panel, The 200 amp panels are sized (number of breaker slots) based on the job requirements.

 

[jbfan]

What's the reason to go with a 400 amp service?

Are you having issues, adding on to the house?

Can the transformer that supplies your house handle the increased load?

 

[firebob]

I think you should talk to your power company first and get a list of meter bases they will let you use. It might be on there web site. Different power company's have different standards when it comes to meter boxes.

It would also be a great time to think if you ever want a generator or solar and plan for it now.


Where I'm at there is a $25 a month fee for a 320 amp meter base.
Where I'm at the power company will not change the wiring or the transformer till you start using X amount of power or have issues. They use different load charts.

 

[decomo]

JBfan: I am adding a heatpump HVAC which requires 30 Amp for the air handling unit + heater and 50 amp for the condenser. I also have a double wall oven which requires 40 amp, a cooktop at 50 amp, a heat pump water heater at 30 amp, and a dryer at 30 amp - on top of a 100 amp subpanel, plus multiple 20 amps for bathrooms and kitchen and many 15 amps for the rest - and may be some extra room for future charging stations. Currently my panel is maxed out on spaces. The current transformer is at 25 kVA serving three households, and the power company will upgrade it to I believe 50 kVA to accommodate the panel upgrade.

Allan J: Yes, I have wall space. Thanks.
Firebob: Yes for future usage. Thanks.
RJNiles: Thank you.

 

[firebob]

Ok so genset down the line.

I would not get a 400 amp panel unless you have to.

If you want 1 panel on the genset and 1 panel off the genset then a split lug 320 meter base might be the best option. This would give you dual 200 amp panels and would be the cheapest. When adding the genset you would just rewire the feed to the panel.

If you want both panels on the genset then you would go off the meter base with huge wire to the transfer switch and then run to both panels.

I have a 400 amp meter base that had room for 4 breakers on the side. 200 amps to my solar system (not able to back feed), 100 panel for the main floor, and 100 amp panel for the basement. The power from the solar system runs 100 amps to the main floor and 100 amps to the basement. The 2 solar system panels have genset backup.

Don't forget to look at the "earth" neutral separating that will be needed after the first disconnect. Depending on with way you go depends on if and when this will come into play.


A 400 amp service is rated at 320 amps at 80%.
A 200 amp service is rated at 180 amps at 80%.
A 20 amp breaker is rated at 18 amps at 80%.
A 15 amp breaker is rated at 12 amps at 80%

 

[firebob]

My post above has bad math and will not let me edit it...
I have spent to much time in a hospital bed and know it was wrong right after I hit submit, but was not able to fix it due to therapy.

A 400 amp service is rated at 320 amps at 80%.
A 200 amp service is rated at 160 amps at 80%.
A 20 amp breaker is rated at 16 amps at 80%.
A 15 amp breaker is rated at 12 amps at 80%.

 

[brric]

Those ratings are for continuous loads of 3 hours or more. A circuit may be loaded to full ampacity for non-continuous loads.

 

[u2slow]

So many ways to do 400A. Best to work closely with the PoCo on these. (The rules keep changing here.)

Its sucks the cheap way (duplex 200A meter base) doesn't let you do a 100/300A split, for example.

On my brother's shop, its a 400A outdoor meter base (w/CT's) going inside to a 400A transfer switch (future backup gen), and splitter. 225A for use in the shop, and 150A goes off to the house. Nowadays I can't do this outdoor 400A meterbase - PoCo wants an electrical room.

My favourite 400A was a SqD QO/QOB main-lug panel I custom ordered for a seniors home. 30 standard spaces, and the 'main' location was converted to TWO large-frame breaker spaces for branch circuits (kitchen & elevator) Nevermind a $4000 job quote - it was a $4000 panel. :biggrin2:

 

[decomo]

Sorry, I don't understand what a genset is, but i am definitely intrigued. Please explain. Does it require any accommodation/configuration by the electric company? Thanks.

 

[u2slow]

Sorry, I don't understand what a genset is, but i am definitely intrigued. Please explain. Does it require any accommodation/configuration by the electric company? Thanks.

Genset = Generator Set = a backup generator.

Normally all you need is an appropriate transfer switch in your service install. The actual generator can come later.

 

[seharper]

You find yourself on a snipe hunt. You figured "100A service, 100A panel... 200A service, 200A panel... 400A service, 400A panel"... nope. That's where this goes wrong.

400A equipment is commercial tier, and insanely expensive. If you expect/insist on it, you'll be the crazy rich customer the electricians gossip about at the supply house (“he *paid* for that!??").

The way folk set up 400A services is by splitting at the meter to two 200A main panels. These are common, run-of-the-mill $150-200 panels. Neutral and ground are bonded in both.

Loads are divvied up between the panels in some sensible way. If you want to do something clever like that 8-space thru-lug panel, that becomes ONE of the 2 panels (but that thing is intended to thru-lug on to a 40 space panel, don't forget to use the thru lugs! LOL! If you want to put a gen interlock into a panel, you do it in ONE of the panels.

That makes things pretty straightforward.

The 200A panel you already have can be one of the two panels don't let them sell you a total re-do that you do not need.

A genset is an obsolete technology for powering critical loads in your house. It comes with a Van Halen box set on 8-track, a VHS rewinder, and a 6-circuit transfer switch.

If you want some sort of ride-thru-outage capability, ask the installers to layout the system in a way that is not incompatible with a Tesla PowerWall or similar tech at some point in the future. Again you would certainly put this on only one of the two 200A panels, so lay out circuits accordingly. You could certainly fit a PowerWall and a small generator to top it up, for the kind of coin you are talking.

 

[decomo]

Thanks SeHarper. Now we are talking. I looked at those insanely expensive 400 amps panel and wondered why. You are saying I keep my current 200 amp panel and add another 200 amp panel by splitting at the meter. Is this something that requires any work by the power company (assuming the transformer is not an issue). This sounds like the route I want to use since I can still keep the current 200 amp panel and possible move the higher load breakers to the new panel. Is the drop from the power pole to my meter the same for this configuration or some update may be necessary?

 

[seharper]

Yes, you will certainly need a new meter pan and everything between the meter and the weatherhead. But that's not so insanely priced!

 

[jbfan]

Last one I did was a 320 amp meter base with 2 sets of lugs on the load side. One set of lugs fed 1 200 amp disconnect and panel, and the other set of lugs fed the second panel.

Back then the power company supplied the meter pan and lugs.

 

[Let it Snow]

The biggest difference in panel cost is Bolt-On vs Stab-In.
Did you get any specs on that?

 

[decomo]

Let it Snow: I don't know enough to ask for quotes or spec on those specific about bolts-on vs stab-in.

JBfan and SEHarper: About the configuration with a meter base and side panels, is this rough high level image below what you were alluding to?

Also, is this generally the type of meter base?