Panel Capacity Questions

[TurboEuro88]

I've recently installed a new 60A subpanel into my detached garage and I am starting to look at closing the walls up to finish the project off. But as most things go for me, I start looking at "what else can I do while I have the walls open" and I had the thought of adding an electrical drop outside my house for a hot tub I'd like to get eventually.

Here's the rundown on my current electrical wiring:

Main 100A Panel Box:

• AC Condenser (30A)
• Furnace (30A)
• Utility Room (20A)
• Master Bedroom (20A)
• Bedroom 2 (20A)
• Bedroom 3 (20A)
• Bathroom (20A)
• Kitchen (20A)
• Outdoor Outlet (former Garage circuit) (20A)
• Garage SubPanel Feed (60A)

Garage 60A Sub Panel Box:

• Indoor Outlets 1 (20A)
• Indoor Outlets 2 (20A)
• Indoor Lights (15A)
• Outdoor Lights (15A)
• Air Compressor (20A)
• Garage Door/Misc Outlets (20A)

I have space left on both panels to add additional circuits if I need them, more on the subpanel than my main panel. All of my lighting in the house and garage is LED, and all my heat/hot water/stove/oven are gas-fed... thus my overall electrical load is relatively light outside of the air conditioning. That said I am considering doing electric heat in the garage since I don't have any realistic means of getting a gas line to the garage. I was considering a 240v heater, but overall haven't decided how I will heat the garage yet.

With all that being said, do I realistically have the service capacity to add a breaker for a hot tub hookup, and if so does it make more sense to feed it via the main panel or the subpanel? Open to any thoughts on the matter and can provide further clarification if any details aren't clear. Thanks!

 

[AntonLargiader]

What size tub? Looks like they can require 30, 40, 50 or 60A circuits.

Also, only one 20A kitchen circuit? Fridge, microwave, small appliance, everything on one circuit?

 

[Zeke]

Must be an old, old house.

 

[mike93lx]

My kitchen has 5 circuits feeding it.

No electric dryer?

A hot tub is probably OK, but it might be close. Drywall is cheap and easy to patch later. How likely are you to get a hot tub? The are expensive to buy, maintain and operate.

 

[TurboEuro88]

70's build, panel was updated to modern wiring probably 15 years ago. 100A is pretty common in my area unless it's new construction, and rarely otherwise even in gut renovations. Gas serves my furnace, hot water, drier, and stove/oven. Forgot that the fridge is on its own 20A circuit. Microwave and small appliances are the bulk of the Kitchen's load.

I am pretty comfortable with the up front and long term costs associated with hot tubs, but just thinking now would be an opportune time to set things up should I get one. As an alternative I am considering just running empty conduit so it's there if I need to run the wire, but didn't want to waste the materials/effort if my service isn't enough.

When you say "might be close" are you referring to the main panel or sub panel? Or just overall?

 

[mike93lx]

I would not run a hot tub off that sub.

Off the main, probably fine. Worst case, you need to upgrade the service, but in most cases, the POCO won't change your feeder anyway, so it's internal.

 

[Bert_]

A hot tub would run fine off that service even a big one. You have almost no electrical load. An amp meter would show less than 20 amps 90% of the time. Chances are it would even run off the garage sub without problems.

Hard to say though without knowing the actual loads. Saying lights 15 amp breaker, outlets 20 amp breaker really means next to nothing. Tell me something like I have 10 lights that pull 0.8 amps each and a 2hp air compressor.

 

[TurboEuro88]

A hot tub would run fine off that service even a big one. You have almost no electrical load. An amp meter would show less than 20 amps 90% of the time. Chances are it would even run off the garage sub without problems.

Hard to say though without knowing the actual loads. Saying lights 15 amp breaker, outlets 20 amp breaker really means next to nothing. Tell me something like I have 10 lights that pull 0.8 amps each and a 2hp air compressor.

Fair point. Like I mentioned, all my lighting is LED. For example all 10 fixtures in my garage total up to maybe 5A of draw. Don't have a compressor yet, but the one I plan to buy soon draws about 14A. Beyond that it's mostly electronics and small appliances throughout the rest of the house. I'll see about getting an amperage draw reading while my AC is on, which is about the most power I'll be using at any given time.

 

[bergheger3]

you will probably be ok to run a hottub off of the main panel. I wouldn't put it on the sub panel as most hot tubs require 50 or 60A breakers. It will come down to what the actual load is.

Electric heat will eat up a lot of amps, pay close attention to the actual load.

If you can give me actual numbers lamp wattage and how many, number of appliances and what they are, etc etc. I can run a load calc.

know that motors have inrush current of about 600% of the FLA of the motor, it only last about 1 cycle but if your A/C, hot tub, air compress all kick on at the same time you might have an issue upon startup.

 

[AntonLargiader]

I think I'd look at that inrush thing as the biggest load kicking on while the others are running. Compressor, fridge and hot tub running when the AC kicks on, or something like that. And of course take out the obvious non-problems like AC and shop heat running at the same time.

You practically never hear complaints of people tripping main breakers. Overload takes some time to trip; it doesn't happen the nanosecond that the load exceeds the rating.

 

[theoldwizard1]

I am not a sparky so double check. I think you can run a sub off of the main WITHOUT A BREAKER IF it is immediately adjacent to the main panel. Cheaper than replacing the whole main panel.

 

[SGKent]

we are in Nor Cal. The price of electricity has gone from 11 cents a KW to 33 cents a KW plus fees and taxes for the services that add an additional $25 - $45 a month to the bill. It is time of day pricing to offset CO2 creation with power plants due to the Carbon Taxes created by the Dems here. No one knows where all the extra money paid goes. We have only a 125 amp service but with the price of power I can't imagine anyone wanting more power unless they have deep pockets. We know people who for years have paid $200 a month for electricity this time of the year, and with time of day their bills were $650 - $700 last month. It's no wonder there are so many people going in debt again.

My point is I was thinking who wants a larger service with the cost of power here if that way of life spreads all over the USA.

 

[mike93lx]

we are in Nor Cal. The price of electricity has gone from 11 cents a KW to 33 cents a KW plus fees and taxes for the services that add an additional $25 - $45 a month to the bill. It is time of day pricing to offset CO2 creation with power plants due to the Carbon Taxes created by the Dems here. No one knows where all the extra money paid goes. We have only a 125 amp service but with the price of power I can't imagine anyone wanting more power unless they have deep pockets. We know people who for years have paid $200 a month for electricity this time of the year, and with time of day their bills were $650 - $700 last month. It's no wonder there are so many people going in debt again.

My point is I was thinking who wants a larger service with the cost of power here if that way of life spreads all over the USA.

Having larger service doesn't mean your bill goes up... Just means you have more headroom if it is needed. Not sure how your political opinion factors in with the OP's decision to get a hot tub though...

 

[wyliesdiesels]

I am not a sparky so double check. I think you can run a sub off of the main WITHOUT A BREAKER IF it is immediately adjacent to the main panel. Cheaper than replacing the whole main panel.

A subpanel does not need a main disconnect if its in the same building as the main.

we are in Nor Cal. The price of electricity has gone from 11 cents a KW to 33 cents a KW plus fees and taxes for the services that add an additional $25 - $45 a month to the bill. It is time of day pricing to offset CO2 creation with power plants due to the Carbon Taxes created by the Dems here. No one knows where all the extra money paid goes. We have only a 125 amp service but with the price of power I can't imagine anyone wanting more power unless they have deep pockets. We know people who for years have paid $200 a month for electricity this time of the year, and with time of day their bills were $650 - $700 last month. It's no wonder there are so many people going in debt again.

My point is I was thinking who wants a larger service with the cost of power here if that way of life spreads all over the USA.

Time of Use rates for residential customers have not been made mandatory.

Why are people switching? Thats their own fault.

 

[bergheger3]

Electricity usage is billed per KWH used. The size of your service has nothing to do with usage.

I'm fortunate enough to live in the midwest so KWH is cheap. I feel bad for the people on the coast.

 

[theoldwizard1]

I am not a sparky so double check. I think you can run a sub off of the main WITHOUT A BREAKER IF it is immediately adjacent to the main panel. Cheaper than replacing the whole main panel.

A subpanel does not need a main disconnect if its in the same building as the main.

But, can the sub panel feed be directly tapped off of the the main panel BEFORE the main breaker (I think I just answered my own question NO !)

 

[SGKent]

A subpanel does not need a main disconnect if its in the same building as the main.

Time of Use rates for residential customers have not been made mandatory.

Why are people switching? That's their own fault.

The rate here was 9 cents a KW hour.

It is now mandatory time of day unless you request a fixed rate (allowed one time request which is higher than combined time of day.):

11.66 cents between midnight and noon.
16.11 cents from noon to 5pm and 8pm to midnight, and weekends
28.25 cents from 5pm to 8pm (when the AC, TV are on and you will be in the garage working)

system fixed price additional $20.20 plus fees and taxes

Or one can agree to 16.49 cents KW plus the system fixed and fees up from 9 cents 24/7. PGE, SDGE, and SCE are much higher now due to time of day. If you don't have mandatory time of day you will.

 

[wyliesdiesels]

I will havw to check again, but last time i did a rate comparison, Pacific Graft and Extortion’s TOU was optional and the first tier rate was .21 cents for just under 500Kwhr

BTW, in reply to your last sentance, i will never have mandatory time of use rates because i dont have PG&E electric. I have MID- modesto irrigation district which is FAR lower than Profits Gone Elsewhere.

I started comparing many of the PoCos several years ago and discovered MID TID Merced ID and SMUD are far lower than Pacific Gasp And Extortions rates.

In the summer I pay .1449 and .1808.

In the winter, i pay .1201 and .1449

 

[MikeF2316]

I will havw to check again, but last time i did a rate comparison, Pacific Graft and Extortion’s TOU was optional and the first tier rate was .21 cents for just under 500Kwhr

BTW, in reply to your last sentance, i will never have mandatory time of day because i dont have PG&E electric. I have MID- modesto irrigation district which is FAR lower than Profits Gone Elsewhere.

I started comparing many of the PoCos several years ago and discovered MID TID Merced ID and SMUD are far lower than Pacific Gasp And Extortions rates.

In the summer I pay .1449 and .1808.

In the winter, i pay .1201 and .1449

I am impressed with how many things PG & E stand for.

 

[MattT]

Depending on property layout a 200A meter main might be a good option. Rhen feed the garage and hot tub direct from it and not worry about overloading anything.

Since the exiting main is only 15 years old it can probably be converted to a sub fairly easily.

 

[wyliesdiesels]

I am impressed with how many things PG & E stand for.

Pacific, Gasp & Extortion
Pacific, Graft & Extortion
Profits, Gone Elsewhere
Profit, Gouge & Execute
Penalize, Gaff, & Extort

I could go on and on...

sadly, theyre all true....

 

[TurboEuro88]

Depending on property layout a 200A meter main might be a good option. Rhen feed the garage and hot tub direct from it and not worry about overloading anything.

Since the exiting main is only 15 years old it can probably be converted to a sub fairly easily.

Likely wouldn't change much about the physical layout of my electrical system. Pretty comfortable with the garage, etc running as a sub of the main as it affords a shutoff on both ends of the feed line. Realistically though I have no idea how much my electrical provider would charge to upgrade my service to 200A. I can handle upgrading the downstream equipment

Haven't been able to get a clear understanding of my amperage loads yet. Been looking for my multimeter and I am beginning to suspect I left it at my parent's house. Oh well. It would seem most hot tubs require a 40-50A 240v breaker which realistically is pushing the limit of my current service. Fortunately this isn't a present need so I think I am going to see if I can at least install empty conduit from my main panel down into my crawl space while I have easy access to the wall under the panel box. I can always add the wire/breaker later on.

For those curious, I am only paying about $0.056/KWh here in NE Ohio, so my monthly costs wouldn't be all that bad to add a hot tub to my usage. Just a matter of whether my service can handle it with everything I already have.

 

[mike93lx]

Your utility won't change anything, more than likely. Normally the feeder from the street stays the same, it's the wire on your house, the meter pan and main panel that get swapped

 

[MattT]

Likely wouldn't change much about the physical layout of my electrical system. Pretty comfortable with the garage, etc running as a sub of the main as it affords a shutoff on both ends of the feed line. Realistically though I have no idea how much my electrical provider would charge to upgrade my service to 200A. I can handle upgrading the downstream equipment

By property layout I meant where your meter is relative to everything else. Is the AC condenser near it? Could the garage feed be easily moved to it? Could you feed the hot tub direct from it without digging half the yard up?

When I put my meter main in the light company didn't charge me anything for the disconnect and reconnect. And no code enforcement here so I avoided that cost and aggravation. You can figure on a few hundred in materials but it could end up costing a lot more than that depending on location.

It would seem most hot tubs require a 40-50A 240v breaker which realistically is pushing the limit of my current service.

IMO yes it's pushing it and would definitely be too much for the garage panel which you also want to run electric heat from.

 

[TurboEuro88]

This is all good to know. I am probably a year or two at least before a hot tub or any kind of service upgrade happens, honestly, but I'd rather go into it informed. Being that I have a 100A main shutoff in a box next to my meter outside, would the utility's responsibility be everything up to that shutoff? Curious to know where my responsibility starts on the upgrade.

 

[MattT]

Being that I have a 100A main shutoff in a box next to my meter outside, would the utility's responsibility be everything up to that shutoff? Curious to know where my responsibility starts on the upgrade.

On my overhead service there are splices in the run between the pole and the house. That is where the light companies wiring meets my wiring. Best to ask locally because some areas do things differently.

Also since you already have a 100A disconnect outside, your house panel may already be configured as a sub panel. If it is that'll make changing to a meter main easier if you decide to go that route.

 

[mike93lx]

On my overhead service there are splices in the run between the pole and the house. That is where the light companies wiring meets my wiring. Best to ask locally because some areas do things differently.

Also since you already have a 100A disconnect outside, your house panel may already be configured as a sub panel. If it is that'll make changing to a meter main easier if you decide to go that route.

Interesting. I've always understood it to be the POCO owns the wire to your house, you own everything from there except the meter. At least that is how it works around me.

 

[wyliesdiesels]

Some pocos will only run their drop wiring up to x amount of feet. Then its on the property owner to run it the rest of the way.

 

[MattT]

Interesting. I've always understood it to be the POCO owns the wire to your house, you own everything from there except the meter. At least that is how it works around me.

Maybe I didn't explain it properly. My side is only a couple feet out of the weatherhead not halfway to the pole. In the picture left of the splices is light company and everything to the right is mine. Other than the meter obviously.

 

[mike93lx]

Maybe I didn't explain it properly. My side is only a couple feet out of the weatherhead not halfway to the pole. In the picture left of the splices is light company and everything to the right is mine. Other than the meter obviously.

Yes, that is completely normal. Your description made it sound like to me that it was somewhere in the middle of the run

 

[TurboEuro88]

I had honestly forgotten about there being a splice just before the weatherhead... DUH!... but that does make wonder how that works if the Electric provider is the one responsible for installing the meter, yet I am responsible for the wiring. Has anyone gone through the process of upgrading service and can speak to the overall process of how that all works, especially if you're doing the wiring downstream of the meter yourself?

 

[MattT]

I had honestly forgotten about there being a splice just before the weatherhead... DUH!... but that does make wonder how that works if the Electric provider is the one responsible for installing the meter, yet I am responsible for the wiring. Has anyone gone through the process of upgrading service and can speak to the overall process of how that all works, especially if you're doing the wiring downstream of the meter yourself?

The basic process is the light company comes out and disconnects the service at the splices. Then you, or your electrician, performs the upgrade work. When it's all done the light company comes back out and reconnects to your new wiring and plugs their meter into your new meter socket. But if permits are involved or your light company are dicks it can be much more complicated.

 

[mike93lx]

The basic process is the light company comes out and disconnects the service at the splices. Then you, or your electrician, performs the upgrade work. When it's all done the light company comes back out and reconnects to your new wiring and plugs their meter into your new meter socket. But if permits are involved or your light company are dicks it can be much more complicated.

Yup, exactly my experience. Pull meter, disconnect feeder. Sparky does work, they come back out and connect. Not a big deal if your electrician is on his game and doesn't screw around

 

[TurboEuro88]

Good to know. Suppose it's possible to go a day or two without power to the home if the Electric Provider drags ***? Either way I'll definitely keep this in mind whenever I get around to renovating the utility area where the panel is.

 

[mike93lx]

Good to know. Suppose it's possible to go a day or two without power to the home if the Electric Provider drags ***? Either way I'll definitely keep this in mind whenever I get around to renovating the utility area where the panel is.

I think they should be able to disconnect in the am, reconnect in the pm. I wouldn't want to worry about all my food or running constantly on a generator just to give a POCO leeway

 

[MattT]

Either way I'll definitely keep this in mind whenever I get around to renovating the utility area where the panel is.

If you go to a meter main outside you might not have to do anything inside. Worst case would be pulling a new feed to the house panel and separating the grounds and neutrals to convert it to a sub panel.

I think they should be able to disconnect in the am, reconnect in the pm.

That should be possible. Depends on how co-operative the light company is and whether code enforcement is involved. When I did mine the first time they came out they only pulled the meter. Second time they just cut the wires at the weatherhead but didn't tape the ends or drop the wires. Rubber gloves and a fiberglass step ladder took care of that