Question for the Electricians

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ramcharger

ramcharger

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Yesterday was slow at work so I spent the day moving stuff and digging a little deeper into the garage electrical. It's not good, lol. Without getting into detail, I will say say that it's not to code. Anyway, got a few questions:

1. What would an electrician charge to replace a 100A sub panel with a 200A panel? Right now it's got a 100A subpanel on the outside with a seperate 60A feed for the AC (which is too big as the AC is rated @ 30A/230V) and a feed to the interior 100A breaker panel.

2. I'd like to run 100A service to the garage. 50A service would certainly do for my present needs, but I only want to do this once and have plenty of room for expansion. I was thinking 2 awg triplex due to the new NEC codes which would give me a 2 hots, an insulated nuetral and a uninsulated ground. The problem is, I can only find triplex 6 awg. I take it I'll have run individual cable like SE? Is there SE cable rated for direct burial? I know that even if I run PVC conduit it still has to be rated for direct burial.

I do know that I still have to add two ground rods at least 8' apart at the garage even with two hots, a nuetral and a ground from the sub panel at the house. BTW, I could do the subpanel at the house myself but I'd have to call the power company to shut the power off at the meter... Honestly, I'd rather leave that part to the professionals.

Thanks in advance!
 
I priced all the stuff to run 100A to mine using #4 with #6 N and G and PVC (OK in FL) and it was almost $600 in materials for a 70 ft run, not including a panel box...and that was using an existing pipe from the inside of the house to the outside.

I imagine an electrician would generally charge about the same for labor as the parts cost, unless the work is REAL easy or REAL difficult.

I found during the research that my existing pipe would only handle #6, which would limit me to 60A service, and running new would involve 4 more 90* bends.

I ended up running the pipe underground, but only pulling #10 for the 220 compressor ($125 for UG romex and $60 for 1 1/4 PVC), and I already had a 20A lighting and recep circuit.

Got my comp going and invested a little in doing it right when the time comes.

I'm NOT an electrician, but did work as an apprentice for a little over a year, and spent another 5 years in high end building maint.
 
Contractors in our area have been known to charge 4x the $$$ of materials....least the few I have spoken with.....
 
Hello ramcharger,
I have some questions first.
What is the size of the service from your utility company?
What is the reason for adding larger subpanel?

It is pointless to add larger subpanel if your utility service remains the same. It is equal to trying to run 2" fire hose from 1/2" garden hose.
Now if your power usage is still at the same level but you are runing out of space for additional circuitbreakers you can get subpanel of the same capacity but with the greater number of the spaces for circuitbreakers.
Second choice would be to install 1/2 space circuitbreakers which will give you double the number of circuits.
In any case be careful while you do this, the function of the circuitbreakers is to protect the wires.
In addition if you feed your larger sub panel from smaller main you wil in case of overload tripp the main instead local subpanel.
In addition some local codes do not allow multiple ground rods. In California the ground wire from subpanel is required to be connected to the ground rod at the main.
Ramcharger good luck with your endevoir
Zoran
 
sounds like the garage is detached from the main house. if so i'm pretty sure the garage panel will need it's own grounding and not be tied into the house ground.
you could get a couple electricians come out and give you a written estimates, everything should be written out that way and you'll know what local code expects. also see about working a deal where you do alot of the rough labor (trenching, ect) and cut the price
 
Isn't it cheaper and faster to run extension cords from the house?

LOL, just kidding.

Really, just kidding.

I had to remove Romex from a house that I sold because it was no longer to code even though it was fine when I bought the house! The extension cords that I had were OK but the Romex was not. CA --- go figure.
 
I know here that armored cable is no longer allowed outside of walls. Romex is now allowed in conduit. GFCI need to be tamper reistant, outdoor box's, the plastic ones, need to say weather resistant on them...
 
YY1 said:
I priced all the stuff to run 100A to mine using #4 with #6 N and G and PVC (OK in FL) and it was almost $600 in materials for a 70 ft run, not including a panel box...and that was using an existing pipe from the inside of the house to the outside.

I imagine an electrician would generally charge about the same for labor as the parts cost, unless the work is REAL easy or REAL difficult.

I found during the research that my existing pipe would only handle #6, which would limit me to 60A service, and running new would involve 4 more 90* bends.

I ended up running the pipe underground, but only pulling #10 for the 220 compressor ($125 for UG romex and $60 for 1 1/4 PVC), and I already had a 20A lighting and recep circuit.

Got my comp going and invested a little in doing it right when the time comes.

I'm NOT an electrician, but did work as an apprentice for a little over a year, and spent another 5 years in high end building maint.
Click to expand...

It's against code out here to run more than one feed to a detached outbuilding so I won't be going that route, but thanks for the info.

inkjunkie said:
Contractors in our area have been known to charge 4x the $$$ of materials....least the few I have spoken with.....
Click to expand...

Good info!

Dartzart said:
Hello ramcharger,
I have some questions first.
What is the size of the service from your utility company?

The existing sub panel right from the meter that splits out 100A to the home panel and 60A to the compressor is rated at 125A and has two 100A breakers and two 60A breakers.

What is the reason for adding larger subpanel?

To provide 100A for the home/air conditioning and 100A for the garage

It is pointless to add larger subpanel if your utility service remains the same. It is equal to trying to run 2" fire hose from 1/2" garden hose.

The meter is rated at 250A, so I assume I can safely go with a 200A sub. Maybe I should double check the wire gauge coming out of the meter?

Now if your power usage is still at the same level but you are runing out of space for additional circuitbreakers you can get subpanel of the same capacity but with the greater number of the spaces for circuitbreakers.
Second choice would be to install 1/2 space circuitbreakers which will give you double the number of circuits.
In any case be careful while you do this, the function of the circuitbreakers is to protect the wires.
In addition if you feed your larger sub panel from smaller main you wil in case of overload tripp the main instead local subpanel.

No issue with breakers other than the main. Just to make things clear, there's the one and only sub-panel that connects directly to the meter. That sub has 2 100A breakers that supply the house and two 60A breakers that supply the air conditioning (which are too big, I checked out the AC unit and it's rated at 30A).

In addition some local codes do not allow multiple ground rods. In California the ground wire from subpanel is required to be connected to the ground rod at the main.
Ramcharger good luck with your endevoir
Zoran
Click to expand...

From what I understand from the NEC codes, not only would I have to have a a seperate ground wire from the nuetral on my garage feed, but also ground with two ground rods at the garage that are bonded together and at least 8' apart. Thanks for the info Zoran! That was a very helpful first post.

kursplat said:
sounds like the garage is detached from the main house. if so i'm pretty sure the garage panel will need it's own grounding and not be tied into the house ground.
you could get a couple electricians come out and give you a written estimates, everything should be written out that way and you'll know what local code expects. also see about working a deal where you do alot of the rough labor (trenching, ect) and cut the price
Click to expand...

All I need is the subpanel and I'll do the rest. :)

DFX 340 Duster said:
Isn't it cheaper and faster to run extension cords from the house?

LOL, just kidding.

Really, just kidding.

I had to remove Romex from a house that I sold because it was no longer to code even though it was fine when I bought the house! The extension cords that I had were OK but the Romex was not. CA --- go figure.
Click to expand...

They do that because they figure that the extension cords won't be permanent. Goofy, I know.

inkjunkie said:
I know here that armored cable is no longer allowed outside of walls. Romex is now allowed in conduit. GFCI need to be tamper reistant, outdoor box's, the plastic ones, need to say weather resistant on them...
Click to expand...

From what I understand Romex is allowed in conduit, but not underground and there is a density requirement to allow the heat to dissapate. Thanks Ink, great info!
 
Sounds like you've done your homework.

2 feeds is OK here as long as they're seperate circuits, and not into the same sub-panel.

Since the comp is the only ting on that panel, I'm OK.

Definately a seperate neutral and ground from the main.

FL says do not bond subpanel grounds.....

There is a raging debate about grounding and ground rods on outbuildings, especially metal ones. Apparently the NEC can be interpreted a couple different ways.


...and Lowes was cheaper than Grainger for the wire /foot.
 
Just for everyone's information that may not know the rules, the NEC (National Electrical Code) is only for reference and can only be used if the authority having jurisdiction (your state or local district) has adopted it. Many states have adopted the NEC in it's entirely but many other cities and states have more stringent requirements. You need to know what your local codes are so you are in compliance.
 
if you want to go overhead, the wire you are looking for is "quad-plex". Around here they sell it at lowe's up to around a #1/0. Keep in mind that tri-plex and quad-plex are aluminum conductors, so size the wire accordingly. Bigger than #1/0, we have to go to electrical supply houses to get it cut to length, always in stock there!!!!!!!!:thumbrig: be careful
 
I swapped my home panel from 100a to 200a. I did not require the "hydro" company to change their lines to the mast. However, by code, I had to increase the diameter of the mast to support the req'd heavier cables through the meter. Since I switched from the Federal Stab-Lok welding circuit breakers to Cutler Hammers, it required new 200a panel and breakers. I have three sub-panels (soon to be 4, our code limit here) of 100a each, and yes, bonding bar between neutral and ground must be removed on sub-panels.

There is a cable which was developed here in Canada by the mining industry which is referred to as Tek cable. It is approved here for underground use without conduit. It is a heavy armor with a plastic sheathing. Pricey, but I used it inside for my sub-panels and will use it for any underground in the future.

Its not a difficult job if you're comfortable with it. We are allowed to take out the permit as long as "we" perform the work,

Step 1 - determine whether supply to mast is sufficent. Your electrical company should provide this info, and I believe change it at their expense if needed.

Step 2 - prebuild your mast mast to code specifications.. eg. diameter, sealing, and to ensure it is above minimum code height for your area

Step 3 - purchase panel, and all breakers required. Be aware that existing wiring may not offer excess lead length in the existing box to relocate breakers in new box

Step 4 - Obtain permit, and do like I did, have mast pre-inspected before installation.

Step 5 - tell inspector which day and confirm that inspection can be done later in the day. My brother was slapped with a $400 bill to have an inspector come after 4:30pm (we did his as well). You will require an inspection before the electrical co. can reconnect your power (very important)

Step 6 - Schedule power company for early AM disconnect.

Step 7 - Wake up early on the day, make a fresh pot of coffee, and hope that all the pre-planning allows you to have power that evening. :)

Grant
 
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