Adding an electrical generator breaker to main service panel inside concrete home

P

Papote

Joined
5 Jun 2018
Messages
1
Reaction score
0
Country
United States
I have the service panel pictured below and I'm trying to add a Generator Interlock breaker to feed my house via a generator. I'd like to have a manual transfer switch inside the fuse box where I can set whether to allow electricity from my main utility or from my generator. I already have a L14-30 power inlet box for connecting my generator. Since this fuse box is inside a concrete wall, I plan to later install one of those breaker home surge protectors. The cables from the mains go to a roof breaker box for my AC inverter mini splits on the roof (That's how the technicians installed it).

I'd like to have some recommendations and how I can go about it. If it is possible to change the innards of the panel to accommodate more breakers, without having to completely remove it since it is in the concrete wall or some other suggestion. I'm no expert, but now some basics.


Service Panel



L14-30 power inlet box



I know I probably don't have much room in this fuse box and will probably need to have it replaced. I need some recommendations on how to go about this while trying to save the current breakers that work fine.

BTW, the cables that are coming from the main leads are from 2 AC inverter mini split units that were installed. I'd also would like to add those to a breaker. They do already have one on the roof.

Generator interlock breaker example



Main breaker (Outside next to electrical meter)

AC Roof Breaker panel
 
Welcome to diynot.com. This is mainly a UK site (the .com domain may have fooled you) so you may not get a lot of help. But one thing is for sure- if you're not an expert (as you've admitted) then you probably want to stay away from DIY-ing something so potentially dangerous.

I'm not sure how solar panels are set up in the USA for feeding back into the grid (or even if you do that) - over here if they are set to backfeed they are also set to shut down if grid power is lost. If you apply generator power at the wrong part of the circuit then the panels may or may not energise and potentially give you overvoltage problems (and/or energise the distribution network, which is a Bad Thing)

The main issue over here on generator setups is ensuring that your generator cannot possibly under any circumstances ever end up feeding back onto the distribution network.

Find yourself an electrician- in this country you'd need a commercial or military-trained sparks, most domestic contractors wouldn't have the expertise.

The other option (which I've used myself on the rare occasions we have power cuts over here) is to make sure that the stuff I want to power during a power cut (heating control, cable modem, fridge, freezer) are connected by plug and socket not hardwired in, and that I have enough extension cables to hand to power them and some light and anything else I want for a few hours. Messy but safe and cheap.
 
This video details an Automatic generator changeover switch
(noting that this is not CE and being uncertified Chinese has its own risk) and also details the very real issue of generators powering the lines back away from the house putting the lives of any operators at risk who are working ion the lines.

For real use, I would want one of these: https://www.gencontrol.co.uk/ats--mains-gen--1-ph.50a.html
 
Last edited:
While I'm not a electrician nor do I know anything about US electrics configurations...
Looking at that service panel, you have 2 thick wires coming from the left up then down into the bank of breakers that then supply several sets of thinner wires going elsewhere.

However, there is also a pair of thinner unfused wires in the same terminals. Whats this for, where do they go and surely its not good practise to run a thinner cable from such a potentially unfused higher current supply than that cable can take?
 
I am not an expert in amercian wiring but what I would look to do is install a new main panel that can accomodate your additions (including the interlocked generator breaker) and then convert the old panel into a subpanel. It looks like it may already be most of the way there with an external main breaker and with isolated neutral bars.
 
You must log in or register to reply here.
Back
Top