Electrical Wiring in the Home/NEMA L14-30R


Greetings and thank you for your help...I bought a house with a six circuit transfer switch already installed and now I am thinking about purchasing a generator...my plan is to install a PB-50 weather tight box on the outside of the house, punch through the basement wall next to the transfer switch and install another PB-50...then make up a two foot female to female 10/3 w/ ground jumper...my questions are: 1) does it matter which side of the L14-30R I connect the respective hot legs? Phase being my concern and 2) do you see any problems with this design? My intuition tells me that since its all down stream of the main panel that the phase is not an issue but I just need a little hand holding here.




From the description of what you want to do here it sounds like the 6 circuit transfer switch already has a 4 wire male twist locking plug built into it. Not all of them do.

The cable from the outside PB-50 should go directly into the 6 circuit transfer switch. Even if it already has a twist locking plug built into it just remove it, blank the hole, and connect the wires from the cable coming from the PB-50 outside to the same wires the the plug was connected to. White to white, green to green (or bare) black to black and red to red. This is faster, simpler, better, easier and cheaper than doing it the way you proposed.

As to "phasing" its really about having the loads "balanced" between the two "hot" legs in the panel. In other words you don't want your heavy users of power such as the refrig, sump pump, freezer, ac, etc all on the red leg or all on the black leg. Try to balance half on the red and the other half on the black. This way you won't over load either of the two "hot" legs coming from the generator. In other words 3 of the circuits in the transfer switch will be on the red leg and 3 will be on the black. Know which circuits in the panel are connected to the red or the black so you can distribute your loads accordingly. When you have utility power this is usually not an issue because you have plenty of power but when you have a small generator as you do with not that much power
this becomes an important consideration.

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Electrical Wiring in the Home

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Licensed Master Electrician (32 years) 6165B Contractor in Closter New Jersey with 40 years total experience in Residential - Commercial - Industrial work. Emergency Service - General trouble shooting and repair work - ONAN & GENERAC generator installation - Paddle fans - Kitchen & Bath exhaust fans - AC lines - Smoke detectors - Telephone lines - Cable TV lines - Computer network cabling - Exterior lighting - Recessed lighting - Security lighting - (200 - 150 - 100 amp service up grades) - Electric Heat - New circuits - New appliance hook ups - and more ! FREE ESTIMATES 201-358-1552 Fully Insured


Licensed contractor in Closter New Jersey.

"The Frank Williams School of Electrical Construction". My dear old boss is 100 ! and still going God Bless him. I started working for "Tenafly Electric" right out of high school at 19. He was tough but I learned more working for him in 8 and half years than most guys. We did mostly industrial work while doing some commercial and residential so I was fortunate to be exposed to all 3 areas of electrical construction. The guys I worked with were all good guys and I stay in touch with some of them still. Most of us went into our own buisness's which says something about the caliber of the guys I worked with. We had some interesting clients : Wella Corp. of shampoo fame, Farah Fawcett etc, I didn't buy shampoo for 10 years. It was a great place to work. Pan Am the former airline just before they went under, another great place to work, nice clean environment. C&C Metals, the largest button manufacturer in the US at that time, a not so clean environment but a very interesting place to work, lots of machine's cranking out buttons of all kinds but you had to be on your toes, it was a potentially dangerous place to be . All kinds of action going on around you.

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