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Discussion Starter #1
I am removing a 150 amp service panel and installing a new 200 amp service panel because I am constructing a new garage and need more circuit space. I have pulled my construction permit and my electrical permit from the city. I am comfortable with rewiring the panel and running the new circuits but I am not sure about how to deal with the meter can and the wires up and out the weather head.
When the power company pulls the meter will they cut the wires leading to my weather head?
Can I go with the conductor table in the NEC for carrying a 200 amp load and use that size conductor to go from my new panel up into the meter can and up and out the top of the weatherhead? Or does the power company have some other standard?
If I understand correctly the wires must be continuous from the panel up going thru the meter can and out the weaterhead - is that correct? So, I guess I just strip the insulation from the wire for connection in the meter can - is that correct?
How much length of wire do I need to leave hanging out of the weather head for the power company to hook me back up?
Thanks for your help.
 

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If you just needed more "circuit space" wouldn't it be easier and cheaper just to put in a subpanel off your main?

Every POCO has different requirements, check with them. In my case I had to leave 3' of wire beyond the weatherhead.

What size wire do you have now down to the meter pan?
 

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To answer the question.
1-Use the tables in the NEC for a 200 amp service.
2-The wires can not be, continuous because they need to hit both sides of the meter.

Inside the can, you will see incoming and outgoing, and neutral lugs.

3-I leave about 3' out of the weatherhead.

If you just need extra slots, add a subpanel.
If you are going to exceed the current 150 amps, then you need to upgrade.
 

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Discussion Starter #5
Thank you for the help. My 150 amp panel was full of tandem circuit breakers, so I did not see a good way around not going up to the 200 amp service panel. With more capability from my serivce panel I do plan to run service to a sub panel in the garage.
Thanks!
 

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Thank you for the help. My 150 amp panel was full of tandem circuit breakers, so I did not see a good way around not going up to the 200 amp service panel. With more capability from my serivce panel I do plan to run service to a sub panel in the garage.
Thanks!
You didn't say if you actually needed 200 amp service or just more spaces.
If 32 spaces would be enough then this is a lot easier than upgrading to 200 amps....
http://www.homedepot.com/Electrical-Breakers-Distribution-Load-Centers-Load-Centers-Main-Breaker/h_d1/N-5yc1vZbm30/R-100193092/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053
 

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"I am removing a 150 amp service panel and installing a new 200 amp service panel because I am constructing a new garage and need more circuit space."

If you only need more circuit space just replace the panel with a new 40 space panel or add a sub panel. Even if you don't think you have room in the panel for a breaker to feed the sub panel you could move some existing branch circuits to the new panel to make room. Going from 150A to 200A is not a significant upgrade. Trust me I have a 150A service and I won't change it unless I decide to go all electric and add a hot tub.

If you want to do all that extra work though you will have to set up a meet with poco or request a pigtail so you can do your work without breaking into poco's meter.
 

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Discussion Starter #8
Re: Do you really need 200 amps of service

Do you need 200 amps of service?
Very good question about whether or not I really need to increase to a 200 amp panel or just get another 150 amp panel with more spaces for more circuits.

I performed a "worst case" calculation that assumes each breaker would be loaded to 80% of its rating.
6 circuits X 15 amps X 80% X 120 volts = 8,640 VA
9 circuits X 20 amps X 80% X 120 volts = 17,280 VA
2 circuits X 30 amps X 80% X 240 volts = 11,520 VA


1 circuits X 40 amps X 80% X 240 volts = 7,680 VA
Total VA before addition = 45,120 VA
Divide 45,120 VA by 240 Volts and you get 188 amps which is above the existing panel rating of 150 amps even before the garage addition. So, I thought it would be better to go with a service panel upgrade.
 

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Your calculations do have some merit but I really doubt that you would ever have all your circuits loaded to 80% at the same time.:no:
Load calculations are not done that way and when done properly the calculations take into account that everything in the house will not be active at the same time.
What you've done above pretty much proves you don't need 200 amps..
 

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Very good question about whether or not I really need to increase to a 200 amp panel or just get another 150 amp panel with more spaces for more circuits.

I performed a "worst case" calculation that assumes each breaker would be loaded to 80% of its rating.
6 circuits X 15 amps X 80% X 120 volts = 8,640 VA
9 circuits X 20 amps X 80% X 120 volts = 17,280 VA
2 circuits X 30 amps X 80% X 240 volts = 11,520 VA


1 circuits X 40 amps X 80% X 240 volts = 7,680 VA
Total VA before addition = 45,120 VA
Divide 45,120 VA by 240 Volts and you get 188 amps which is above the existing panel rating of 150 amps even before the garage addition. So, I thought it would be better to go with a service panel upgrade.

I'm sure I'll get corrected on this but this is the way I size a dwelling service based on the NEC.

Step 1: Sq. ft of living area x 3VA
Step 2: Two 1,500VA small appliance, One 1,500VA Laundry
Step 3: Apply lighting demand Table 220.11, 1st 3KVA or less 100%, 3,001-120,000VA 35%
Step 4: Compare A/C VS Heat omit smaller
Step 5: 75% demand for (4) or more fixed appliances. Not for ranges, dryers, heating, or A/C
Step 6: Dryers 5KW minimum
Step 7: Demand for cooking equipment 80%. Use Table 220.19 if you have multiple cooking appliances
Step 8: Largest motor to be increased by 25% and add any other motors
Step 9: Size the service by dividing the total VA by line voltage.

Based on your calculation it looks like you have a 30A AC and 30A for either your range or water heater. Either way your peak demand is probably 100A-125A. I just re-read your post and saw that you also have a 40A circuit, even after plugging that in you are still within range for your 150A service.

My house had a 150A service when I moved in; I don't plan on changing it and this is what I do! I have a 50A electric oven, 40A AC and a 30A electric water heater.
 
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