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Kevin, Licensed Electrician
Category: Electrical
Satisfied Customers: 3197
Experience:  30 years Licensed Electrical Contractor in Illinois, Adjunct College Electrical Instructor, Former Electrical Inspector, Diploma: Digital Electronics, FCC Technician License
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Needing to put subpanel in my shed, 100 amp service with a

This answer was rated:

needing to put subpanel in my shed
JA: I'll do all I can to help. How long have you been dealing with this?
Customer: 100 amp service with a 120ft run is what im needing wireing info for. what size would work best for me in aluminum. 2/2/2?
JA: Do you plan on doing the work yourself?
Customer: yes
JA: Anything else we should know to help you best?
Customer: nope

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

1) What type of loads, how many circuits and voltage is required in the shed?

1) Are you looking to install a 100 amp feeder circuit to the shed or how many amps?

Customer: replied 3 months ago.
ill be using wood working tools and air compressor. possibly a 120 volt welder. not sure how many circuits ill be running but i have a 20 slot box which I highly doubt ill ever use all of. basically lights and receptables for normal use.
Customer: replied 3 months ago.
100 amp yes

OK, standby for a few minutes as I need to calculate the voltage drop.

1) The National Electrical Code recommends that the voltage drop be limited to a max of 3%. Using 2 AWG aluminum is the minimum size for a 100 amp sub-panel feeder circuit and results in a 2.7% VD on a 240 volt/100 amp feeder at a 120 foot run. Therefore, the 2 AWG aluminum is code compliant.

2) The feeder circuit needs to be a 4 wire circuit comprised of 2 hots, 1 neutral and 1 equipment grounding conductor. The ground wire can be sized as 6 AWG aluminum.

3) The shed will require a quantity of two 8 foot ground rods spaced a minimum of 6 feet apart. 8 AWG copper will be required for the grounding electrode conductor.

4) At the sub-panel, do not install the main bonding screw or main bonding jumper. The neutral must remain isolated from the panel metal enclosure.

1) The sub-panel will require a separate equipment ground bar to land all grounding conductors. Only white neutrals will land on the panel neutral bus bar. If greater than 6 circuits at the sub, a main breaker panel is required.

Any other questions?

1) One more 8 AWG ground wire from the ground rods to the sub-panel needs to be protected in 1/2" conduit. All 120 volt shed receptacles need to be GFCI protected.

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

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


Customer: replied 3 months ago.
Great info. Thanks. Highly recommend

No problem, glad to assist:)


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

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


Any other questions?

Customer: replied 2 months ago.
Thank you Kevin for your help. I'll be doing the electrical tomorrow so if anything comes up I'll let you know.

Just curious, why the negative rating? I provided you with all correct code answers to your questions or did I miss something here?

Kevin and other Electrical Specialists are ready to help you
Customer: replied 2 months ago.
No you did great. I'm not sure why it is giving negative feedback. I've went back to my email 3 times and clicked the 5 star option and it keeps telling me I'm sorry your not satisfied. I'll keep trying because I really do appreciate everything.

Thank you for the positive service rating............much appreciated!

If you have any other questions, just let me know.

Take care and have a great weekend.............Thanks again............Kevin:)

Customer: replied 2 months ago.
You too thanks

Thank you for the bonus.....that was not necessary, but is very much appreciated:)

Take care and Thanks again:

Happy Holidays...........Kevin:)