Convoluted service upgrade

[James L]

I have a service upgrade on a job I took over behind another electrician. He roughed in a basement, then I finished it. He planned a service upgrade from 200 to 300 and added a 100 amp MLO panel across the basement, next to existing 200 amp MLO panel

First picture shows what it looks like now on the outside. Notice a 2-2-2-4 SER stubbed out under the existing 200 amp disconnect.

Second picture shows my first plan:
Orange = 400 amp meter can
Blue = new 100 amp main breaker disconnect
Green = gutter out of meter can, nippled up into each disconnect, with SER also through gutter.

Now they want to add backup generator.
Problem is wall space and possible logistical issues

Third picture shows (in yellow) 300 amp ATS and disconnect. Also in yellow is powwr from meter to ATS. Then in white is power from ATS to that gutter and into disconnects. Gutter would no longer attach to meter can.

But if you notice, the only wall space is on a cantilever. I think I would need to hang the generator equipment low, so as to come in and out of the back of the ATS.

Wondering if it would be better to just hang strut down off the house only low enough to mount equipment, or take the strut all the way to the ground so I can attach pipe to it.

Also curious about how someone would get gas line across all those pipes/phone/catv

I don't know exactly where generator will sit, but more than likely close to all that stuff.

Just looking for thoughts.
Maybe someone sees something from a different angle that might help.

 

[hillbilly1]

Gas line would be easy enough, just a strut rack to bring it out. Instead of coming out of the back of the ATS, why not LB into the bottom? Then the ATS would not have to hang below the cantilever. I’m assuming the ATS is service rated?

 

[hillbilly1]

Looked at it again, you are using disconnect and a non service rated transferswitch, still would be the same, but a service rated tswitch would take up less space.

 

[LarryFine]

Did you say 2-2-2-4 SER, as in a 100 amp service? That ain't right.

I'd have to see the bigger picture to suggest genny placement.

Here's what I would do:

1. Be grateful the inside panel is already unbonded.

2. Replace meter base with dual-lug 400a base.

3. Decide whether 100a or 200a panel be on genny.

4. Get appropriately-sied service-rated ATS.

5. Mount ATS on one side of meter, disconnect on other side, nipple to each.

6. Let sub-contracted plumber worry about gas line.

 

[James L]

..... a service rated tswitch would take up less space.

I don't have the equipment yet.
I drew two cabinets only because I don't know availability. Service rated would be better, for sure

 

[James L]

Did you say 2-2-2-4 SER, as in a 100 amp service? That ain't right.

I'd have to see the bigger picture to suggest genny placement.

Here's what I would do:

1. Be grateful the inside panel is already unbonded.

2. Replace meter base with dual-lug 400a base.

That was my first plan before genny

3. Decide whether 100a or 200a panel be on genny.

Both panels are in finished walls, and both panels have loads that need to be on genny. The 100a was added for the basement, including his office.

4. Get appropriately-sied service-rated ATS.

Hopedully

5. Mount ATS on one side of meter, disconnect on other side, nipple to each.

The 200a disconnect is fixed because SER comes into the back of it.

I don't think here's no room to mount anything to the left of the meter once it goes to 320a can. Maybe ditch some of that communication junk if it's not in use

But crossing over the service riser...you mean go down into the ground and back up?

6. Let sub-contracted plumber worry about gas line.

I just don't want to create an impossible scenario for him

 

[James L]

....why not LB into the bottom? Then the ATS would not have to hang below the cantilever.

I don't know. Maybe height? The ground slopes to the back some.

Maybe I thought it would look cleaner with pipes coming into the back. But that whole side of the house is going to look horrible. A couple of LBs

I had a hard time conceptualizing the generator setup and equipment location because I already had a plan for the upgrade.

I don't do change well sometimes

Thanks for that input

 

[kwired]

Is there enough load there to justify more than 200 amp service?

Or did they add some on demand electric water heater or a lot of electric heat?

Most basement remodel/finishes I ever done seldom add much significant load to what is existing.

 

[James L]

Is there enough load there to justify more than 200 amp service?

Or did they add some on demand electric water heater or a lot of electric heat?

Most basement remodel/finishes I ever done seldom add much significant load to what is existing.

He's going to add a hot tub. The circuit got ran from the 100a sub.

I thought about a manual transfer switch to keep the generator an equipment smaller. Then he could manually turn stuff off before startup.

I've never used a manual TS
Does someone make one for outdoor use?
That would suck having to go out in a blizzard

 

[electrofelon]

So how are you handling generator/non generator loads? Seems logical to put say the non-generator loads on that 100 amp and the generator loads on the 200 amp, but you say there are generator loads in each can stuff be shuffled around?

 

[James L]

So how are you handling generator/non generator loads? Seems logical to put say the non-generator loads on that 100 amp and the generator loads on the 200 amp, but you say there are generator loads in each can stuff be shuffled around?

There are generator loads in each panel.

If I had done the basement rough-in, I would have shuffled things around. As it is, the basement is 99% complete and both panels in a finished wall.

 

[kwired]

He's going to add a hot tub. The circuit got ran from the 100a sub.

I thought about a manual transfer switch to keep the generator an equipment smaller. Then he could manually turn stuff off before startup.

I've never used a manual TS
Does someone make one for outdoor use?
That would suck having to go out in a blizzard

Any other significant load on the 100 amp sub? I think most only have maybe 4-5kw heaters. Pump(s) would draw higher load only when using the spa, but typically only run on a low speed when heating and no users. So even though they may have a 50 amp supply circuit they probably only have around 30 amp demand maybe a little higher if using it.

I wouldn't make anyone upgrade 200 amp service for a hot tub load unless they were really pushing the 200 amp service already.

Use a relay and load shedding features if the ATS has it to isolate the hot tub when on standby power? Many those would still let it run as long as overall demand is low enough.

 

[electrofelon]

There are generator loads in each panel.

If I had done the basement rough-in, I would have shuffled things around. As it is, the basement is 99% complete and both panels in a finished wall.

Wake up James, you didn't answer my question! Is the generator large enough to run everything? Or are you doing load shedding?

 

[LarryFine]

There are generator loads in each panel.

I would move them between panels to create only one genny panel, or you're going to have to supply the entire house, and use two ATSs to do it.

If I had done the basement rough-in, I would have shuffled things around. As it is, the basement is 99% complete and both panels in a finished wall.

Are they next to each other? If so (and maybe even if not) you should be able to nipple (or pipe) between them.

How is the new panel being supplied now?

 

[James L]

Any other significant load on the 100 amp sub? I think most only have maybe 4-5kw heaters. Pump(s) would draw higher load only when using the spa, but typically only run on a low speed when heating and no users. So even though they may have a 50 amp supply circuit they probably only have around 30 amp demand maybe a little higher if using it.

I wouldn't make anyone upgrade 200 amp service for a hot tub load unless they were really pushing the 200 amp service already.

Use a relay and load shedding features if the ATS has it to isolate the hot tub when on standby power? Many those would still let it run as long as overall demand is low enough.

Ope, I forgot the basement also has a steam shower, 10-12kw

I've never used a load shedding device.
Is that something which can be controlled wirelessly? Panels are across the finished basement and in finished walls.

Adding a control circuit is not an option.
That's why I considered a manual TS, so he can turn off those frivolous loads before transferring

 

[James L]

Wake up James, you didn't answer my question! Is the generator large enough to run everything? Or are you doing load shedding?

I've only had one cup of coffee so far

Generator isn't selected yet.
I'm in the pricing/planning stage.

I've never done load shedding, so I don't know how it connects. Wireless control?

I was considering manual TS so he can shed his own loads

 

[kwired]

Ope, I forgot the basement also has a steam shower, 10-12kw

I've never used a load shedding device.
Is that something which can be controlled wirelessly? Panels are across the finished basement and in finished walls.

Adding a control circuit is not an option.
That's why I considered a manual TS, so he can turn off those frivolous loads before transferring

Load shedding is just a contact and is either built into the ATS or is an add on module. They mostly set up to be easy to use with 24V HVAC control wiring - just run a 18-2 from say the AC unit so that it interrupts the control signal to the contactor. Might need a relay and low volt control supply to control other loads if desired, I don't think they are intended to interrupt other than class 2 control circuits as a general rule.

Many do monitor generator load and will allow items to run if overall load is low enough to allow it, and I think they have priority order on which ones will shed first when that might be a factor

 

[James L]

I would move them between panels to create only one genny panel, or you're going to have to supply the entire house, and use two ATSs to do it.


Are they next to each other? If so (and maybe even if not) you should be able to nipple (or pipe) between them.

How is the new panel being supplied now?

New panel has a new SER ran, and it's sticking out the wall under tge 200a main

 

[James L]

Load shedding is just a contact and is either built into the ATS or is an add on module. They mostly set up to be easy to use with 24V HVAC control wiring - just run a 18-2 from say the AC unit so that it interrupts the control signal to the contactor. Might need a relay and low volt control supply to control other loads if desired, I don't think they are intended to interrupt other than class 2 control circuits as a general rule.

Right.
That's what I was thinking.
But I can't add any wiring.

GC finished tge whole basement out without a generator plan in place.

It's going to be whole house

 

[electrofelon]

Ope, I forgot the basement also has a steam shower, 10-12kw

I've never used a load shedding device.
Is that something which can be controlled wirelessly? Panels are across the finished basement and in finished walls.

Adding a control circuit is not an option.
That's why I considered a manual TS, so he can turn off those frivolous loads before transferring

Generac makes these relay modules that simply detect the less than perfect frequency and shut the load off. They might be good to use in a couple spots and then you could just use like a 15 KW-is Genny. Generac smart management module I believe it's called if you want to check it out.