View Full Version : Manual transfer switches for standby generators

11-09-2004, 05:03 PM
I have some questions about these power switching devices for all of the electrical types out there. Firstly, is it possible to build one to spec from service parts to save some money?
Secondly, if I were to buy one of the ready-made switches (http://www.nooutage.com/single-circuit-switches.htm) that are on the market, which one should I get? I mean, I know what requirements I need to meet for the genset (6.3kw running/9.1kw surge, 120/240v, 30a), but I'm unsure what requirements I need to meet for the utility line. Is the 200a main breaker a clue?

[ 11-09-2004, 05:06 PM: Message edited by: Ged ]

Jim H
11-09-2004, 06:34 PM
I'd bet your power company might have some input on what rating you would need for an off the shelf switch.

11-09-2004, 06:45 PM
Thanks, that's probably the best thing to do. I'll give them a call. Also, I'll probably give a call to city code enforcement to find out if I need a permit to install that kind of thing.

Billy Bones
11-09-2004, 07:20 PM
The unit I use is made by square D and cost about a hundred bucks or so. It is a simple 3pos 3 blade switch rated at 100A and has 2 lines in and one line out. Service enters either through line 1 (pole) or line 2 (gen) and leaves the box to go to the main panel. Switch both poles and the neutral but NOT the ground.

[ 11-09-2004, 07:22 PM: Message edited by: Billy Bones ]

11-09-2004, 07:59 PM
Thanks, Billy B. I do need to take a look at Square D's products. Popular Mechanics chose one of their switches for their [URL=http://popularmechanics.com/home_improvement/home_improvement/1998/3/install_backup_generator/print.phtml]article[/ URL] on how to install a backup generator.

[ 11-09-2004, 08:02 PM: Message edited by: Ged ]