How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Kevin Your Own Question
Kevin
Kevin, Licensed Electrician
Category: Electrical
Satisfied Customers: 3203
Experience:  30 years Licensed Electrical Contractor in Illinois, Adjunct College Electrical Instructor, Former Electrical Inspector, Diploma: Digital Electronics, FCC Technician License
71008832
Type Your Electrical Question Here...
Kevin is online now
A new question is answered every 9 seconds

I'm going to redo the service on my house. I have electrical

Customer Question

I'm going to redo the service on my house. I have electrical experience and work for my areas electric utility. Before I look in a code book (at home) I was just looking to see if using a 4/0 4/0 (hots) and a 2/0 (N) aluminum SEC was the proper awg size for a 100a service
Submitted: 1 year ago.
Category: Electrical
Expert:  Kevin replied 1 year ago.

Hello and welcome to Just Answer. My name is ***** ***** I will be happy to assist you with your electrical question.

1) Depends upon the distance from the meter can enclosure to the main panel. For a normal 100 amp service, the service entrance conductors only need to be sized as either 2 AWG Aluminum or 4 AWG Copper. Both of these conductor sizes are rated for 100 amp service.

2) 4/0 Aluminum is rated for 200 amps, but once again all depends upon the distance due to any potential voltage drop in the conductors due to a lengthy run.

3) If using 4/0 Aluminum as the service entrance conductors, the conductor size is fine, except the conductors will not fit onto the lugs of a 100 amp panel. Split bolt connectors or piercing connectors would be required to reduce the 4/0 Aluminum service entrance conductor size to fit onto the main breaker and neutral bus bar lugs.

Customer: replied 1 year ago.
The 4/0,2/0 would be from the weather head to the top of the new meter box. I would use #6 from the bottom of the meter box to the main breaker
Expert:  Kevin replied 1 year ago.

1) You can't use 6 AWG Aluminum as it is only rated for a maximum of 55 amps. 6 AWG Copper is also too small as it is rated for 75 amps. Both are too small as service entrance conductor sizes for a 100 amp service. 6 AWG conductors can easily over load and over heat.

National Electrical Code requires a minimum of 4 AWG Copper or 2 AWG Aluminum for the service entrance conductors. Any sizes smaller will result in a code violation as well a potential safety hazard.

See table shown below:

2) The lugs on the meter can LINE side may also be a tight fit or may not fit at all. Look at the meter can enclosure conductor size label rating to confirm if the 4/0 Aluminum will fit.

Hope this helps………If you have any additional questions, let me know and I’ll be glad to answer them for you.

Otherwise, don’t forget to rate me before you log Off.

The next time you have an electrical question, you can also request for me at: http://www.justanswer.com/home-improvement/expert-your-electrician ……….Thanks…………..Kevin!

Expert:  Kevin replied 1 year ago.

If you have any additional questions, let me know and I’ll be glad to answer them for you.

Otherwise, don’t forget to rate me before you log Off.

Thanks.............Kevin:)

Expert:  Kevin replied 1 year ago.

If you have any additional questions, let me know and I’ll be glad to answer them for you.

Otherwise, don’t forget to rate me before you log Off.

Thanks..............Kevin:)