100 amp to 200 amp Main Panel

[olds]

What's involved in upgrading a 100 amp panel to 200 amps?

 

[Steltek]

Firstly, it is possible the electrical utility may have to make upgrades to the transformer and/or the wiring from the transformer to the service drop, so consult with them before you start this project. You may also need permits and inspections depending upon where you live, so you need to research this.

Then, you'll have to buy and install a 200A distribution panel with a 200A main breaker.

You'll also have to have the meter pulled and the power disconnected at the transformer so you can replace the existing service entrance wiring from the service drop to the meter, and from the meter to the panel (the existing wiring will almost certainly not be large enough to safely carry 200 amps, so you'll probably need to buy enough 2-2-2 SE-U copper cable - I wouldn't touch either aluminum wire or copper coated aluminum wire -- to run from the service drop down to the meter and also from the meter to the new 200A panel). If it is feasible to install a new meter base and service entrance this might be easier as it would allow you to install the 200A panel, then run the 200A service entrance wiring through the new meter base and all the way up to the service drop (which would allow the utility to just switch the meter and service drop over, minimizing down time. You would then be able to dismantle and remove the old service drop, old meter base, and old service entrance wiring at your leisure).

If you do not want to transfer the circuits from the old 100A panel, you can install a breaker in the new 200A panel and use #4 wire (the size required to support 100A) to feed the existing 100A panel (depending upon what you are actually pulling in the existing 100A panel, it might not even require a 100A breaker to feed it). If you instead decide to tear out the old panel completely and just replace it, make sure to buy circuit breakers for the new panel which exactly match the amperage of the breakers in the old panel and place the new panel close enough so you can just transfer the circuits over to the new panel.

BTW, if you have this done and someone suggests installing and bonding another 100 amp panel (which is possible, my sister's house is set up like this with two separate 100A panels), don't do it. Having two 100A panels is not equivalent to a single 200A panel -- if you are going to all the expense and trouble to do this, do it right and don't compromise.

 

[Greenman]

What's involved in upgrading a 100 amp panel to 200 amps?

I'd first question why you need the upgrade.
Labor wise it's not a big deal. Around here the main issue is dealing with PG&E and getting them to come out to swing the service. I've heard of cases where they actually did it when they said they would, but I've never actually witnessed it.

 

[olds]

Thanks for the replies.

I am in Ohio now, no PG&E.

Looking at homes to buy, it's about a 50/50 mix of 100 and 200 amp service.
I'd be running an additional load as I'd be adding 3, 240 volt circuits.
Hot tub, air compressor and welder. I also run a table and chop saw on 120 volts. There also could he a heater running and shop lights.
I like head room.

 

[Red Squirrel]

Yeah as others said the hydro drop from the pole will probably need to be upgraded. Ex: the wire itself, as well as the meter, and maybe even the meter pan. If you have underground feed this won't be easy. But it could be all that is already rated at 200a if it's new enough.

Before you do this though I would ask yourself if you really need that much power, as the upgrade may potentially end up costing you in the long run via a bigger bill. ex: delivery fee or other fees may increase. I'm not positive on that part though, but look into that first.

If you simply want a panel with more spaces you can still put a 200 amp as long as you have a 100 amp fused cut off before the panel. You can also replace your panel with a FPE off ebay and have unlimited amps. (don't do this )

Oh and you can have more than 100a worth of circuits on a 100a panel. You probably won't be running everything all at once. But if you feel you might, then yeah maybe it's worth the upgrade. Ex: A/C, hot tub are loads that could easily be running at same time, then add the oven in the mix, and maybe you have a load of laundry going so dryer and washer too. So yeah you'll want to figure out how many of these big loads you think of using at once and decide if it's worth it.

 

[Greenman]

Thanks for the replies.

I am in Ohio now, no PG&E.

Looking at homes to buy, it's about a 50/50 mix of 100 and 200 amp service.
I'd be running an additional load as I'd be adding 3, 240 volt circuits.
Hot tub, air compressor and welder. I also run a table and chop saw on 120 volts. There also could he a heater running and shop lights.
I like head room.

It's pretty simple to evaluate your actual needs. I've run into a lot of projects where the client thinks they need to upgrade the service, when they will never come close to maxing out what they have.

 

[Paperdoc]

I agree with everything above. I'll just add two points.

1. IF your plan is to remove the old 100 A panel and replace it completely with the new 200 A one, give careful thought to whether the existing branch circuit cables that come into (well, from, really) are long enough to reach the new panel. You may be able to handle that issue simply by having all the old cables enter the new panel near the top where they can reach, and arranging the new circuits you will add to come in at other locations. Worst case for a FEW cables, you might need to replace part of a run or add a junction box.

2. Regarding the service entrance system on the outside of your house, in my area the utility is responsible for the service cable from the pole to your house; YOU are responsible for all of the conduit mast and the cables it contains, the meter base, etc. The wires INSIDE those conduits, of course, need to be heavier for 200 A. BUT that may ALSO mean that the conduit mast / pipe itself must be replaced to allow for that larger wire size.