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 Mike Your Own Question
Mike, Master Electrician
Category: Electrical
Satisfied Customers: 1425
Experience:  Licensed Master Electrician - OnQ Certified Data Voice Audio Video Installer
Type Your Electrical Question Here...
Mike is online now
A new question is answered every 9 seconds

Well, I am building a small cabin in the woods and have a

Customer Question

Well, hello! I am building a small cabin in the woods and have a shed approximately 100 feet from my cabin with a generator and solar panels. I also have a well controller in that shed that powers a deep pump with a 220V connection (plug right now). I want to install a main service panel (200 amps) in the shed and a 100 amp sub-panel in the cabin. What wire will I need to run to service that 100 amp sub-panel and should I wire that for 120V or 220V? Do I have either option? I would like the main service panel to simply plug into the 220V outlet on the generator and all other electrical service to be hard wired into the main panel. Am I mapping this out correctly?
JA: Sometimes electrical issues that that you think will be really complicated end up being easy to fix. The Electrician I'm going to connect you with knows all the tricks and shortcuts. Is there anything else important you think the Electrician should know?
Customer: I have a small solar panel and battery kit with a 12 amp, 1000 watt inverter that presently services a few lights in the cabin via a long extension cord. I would like to be able to have the solar power available when the generator is off and full power available when the generator is on. Thank you!
JA: OK. Got it. I'm sending you to a secure page on JustAnswer so you can place the $5 fully-refundable deposit now. While you're filling out that form, I'll tell the Electrician about your situation and then connect you two.
Submitted: 1 year ago.
Category: Electrical
Expert:  Steven Parent replied 1 year ago.

Hello and good day. A couple things;

1) What is the total output of the generator?

2) The 220V output plug on the generator, how many amps is it rated for?

3) Can you hard-wire off the output?

3) Is it a straight 220V 3-wire? 2 hots and a ground, or a 4-wire 2 hots, a neutral and a ground.

4) Your total demand load in the cabin will determine what you need to run for a service, but if you want to supply 100A at that distance, if you buried a cable you would want to go #2AWG copper or larger if aluminum.

5) You would need a transfer switch to switch between solar and genset for your power in the shed

Customer: replied 1 year ago.
Thanks, Steve. The generator puts out 8,000 running and 13,000 starting watts. I will need to verify the amperage of the 220V output. Cannot hard-wire off the output but for my well controller for now I wired the male plug onto it and I plug in. I will have to go take a look again and refresh my memory if it's a 3-wire or a 4-wire. I don't think it's likely I'll have a large demand load in the cabin at any given time which is why I purchased a 100A sub panel. We may have a wall heater and H20 instant hot running at the same time in theory, and other than that, lighting and basic outlets, two 20A circuits to the kitchen counter, etc. I will also re-measure the run but I think 100' of actual cable length is about right. Any other tips or questions before I make another run out there to confirm the other questions?
Customer: replied 1 year ago.
In theory we may be hooked up to the grid at some point so I'd like to plan on a full panel in the shed (or would move to a future house) so I've been wiring everything with anticipation that we might have straight up power some day. I assume the battery power from the small inverter will have no problem traveling through the buried cable to the cabin (just the opposite in fact, right)?
Expert:  Steven Parent replied 1 year ago.

You would just need to make a transfer system with the panel, genset, and the solar. So you could switch which power source you have supplying the panel and to prevent back feeding. If you think you might be hooked up to the grid at some point, you want to make sure your panel in the shed has a main breaker for whatever amp service you might end up getting. Or you will have to make the necessary changes later on, whichever.

Expert:  Steven Parent replied 1 year ago.

But first you want to see if you have a 120/240 output receptacle from your generator and what amperage

Customer: replied 1 year ago.
I will check that out and get back to you. Thank you, Steven!
Expert:  Steven Parent replied 1 year ago.

You're welcome

Related Electrical Questions