Circuit 07 · 100A · Generators
Standby and portable generator wiring
The storm is not the problem. The four days afterwards are the problem.
Act 02 — The Detail
Monfett Electric wires standby and portable generators across western Massachusetts, including automatic and manual transfer switches, generator inlets, and the subpanel that decides which circuits stay live.
The transfer switch is the whole job
Whatever the generator, the part that matters is the switch that separates your house from the utility. Without one, power flows back down the line toward crews working on it, which is dangerous and illegal in every state. An automatic switch senses the outage and starts the generator on its own, usually inside a minute. A manual switch costs far less and asks you to walk outside and throw it.
Deciding what stays on
A whole house standby unit runs everything. Most people do not need everything. Well pump, furnace or boiler, refrigerator, freezer, a few lights and the outlets you charge phones at will get a family through four days comfortably, and that list fits a much smaller generator on a critical loads subpanel. We size the generator to the list, not the other way round, which is usually the difference between a comfortable number and an uncomfortable one.
What we do
- Automatic transfer switches for standby units
- Manual transfer switches and generator inlets for portable units
- Critical loads subpanels
- The electrical side of a standby install, coordinated with the gas fitter and the pad
- Permit, inspection and utility coordination
Autumn is the season to do this
Every year the first real storm arrives and the phone rings for a week from people who want a generator installed tomorrow. Lead times on equipment stretch, inspectors get busy, and tomorrow becomes November. The quiet months are when this work goes smoothly.
Act 03 — The Answers
It depends on what you want running, and the useful exercise is to write that list before shopping. A well pump, heating system, refrigerator, freezer, a few lights and some outlets will carry a household through an outage comfortably, and that list fits a much smaller unit on a critical loads subpanel. Running the whole house including central air and an electric range needs considerably more. We size the generator to the list rather than to the square footage.
A transfer switch is what separates your house from the utility while the generator is running. Without one, power can flow back down the line toward crews working to restore it. Backfeeding a house through a dryer outlet or a similar arrangement is dangerous and illegal, and it is the reason transfer switches are not optional. Automatic switches sense the outage and start the generator; manual switches cost much less and you operate them yourself.
Usually not the whole house, but more than people expect. Wired through a manual transfer switch to a critical loads subpanel, a decent portable unit will cover heat, water, refrigeration and lighting. What it will not cover is central air conditioning, an electric range and electric water heating all at once. Deciding what goes on that subpanel is the part of the job worth spending time on.