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The $1 transfer switch.

I have a question from a neighbor who asked me why this won't work. He has identified 2 circuits he wants to switch over to a generator. The plan is to break the cable to the circuit(s) where it exits the service panelboard and install a device box. Put in a single pole double throw switch with the common to the load side of the circuit, one switch leg to the panel O/C device and the other to the male socket that he would connect a generator cord to. (one for each circuit). The only issue I can see is the location of the bonding jumper. If the generator has a bonding jumper I suppose you should also be switching the neutral (DPDT switches) but other than that I am having a problem finding a problem. I have even had inspectors say that is not a problem (2 bonding jumpers, one in the separately derived source, since the load is downstream of the grounding point). What do you guys think?

Reply to
Gfretwell
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Install double pole switches and the arrangement is correct for either type of generator. The double pole switches are around thirty dollars apiece. The male inlet fitting is about twenty dollars apiece.

-- Tom

Reply to
Tom Horne

As long as your following the utilities requirements then the installation should be fine. What you describe to me sound a lot like a back feed. Since the neutrals are going to tied together this installation would be sending voltage and current back to the source, the utility transformer. I do not like solid neutrals on transfer switches and will not install them any more. I have seen just to many problems with them over the years.

I suggest he forget the switches and run extension cords. How often does this really happen? (My guess is that the electrical and generator folks are seeing a huge increase in business from what has happened.) Cheaper and less likely to harm the lineman doing his job. I have been that lineman, got nailed in a rural part of AZ from something very similar. I pressed charges and the guy ended up with jail time and a hefty fine. Please people do it right and safely. It only takes 20 milli-amps to kill in the right situation.

Reply to
Zathera

A follow up: I looked in my Soares book and the installation would be legal if: You use a 2 pole DT switch and install the bonding jumper in the generator OR You use Single Pole DT switch and remove the bonding jumper in the generator. The issue is objectionable currents in the grounding conductor to the generator. (there will be a slight rise in the voltage on the generator case) The utility line side would be OK in either case since the only conductor in question is the grounded one (at the service disconnect).

BTW I looked at the Honda EG5000 owners manual and it says that there is NOT a bonding jumper in the generator so it can't be a separately derived source, hence you must bond the neutral at the service. That leads me to believe the solidly connected neutral is correct.

Reply to
Gfretwell

Hey, where can I get these UL rated DPDT 240 volt 30 amp switches?

Reply to
John Gilmer

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Tom

Reply to
Tom Horne

Zathera,

Sorry for the belated comment. I would be interested in any references that you could supply to confirm your point. If you handled say a 5 kV distribution conductor without first testing it for voltage and then grounding it or using hot line techniques, then you were in violation of OSHA and the safety codes of any utilities that I have been associated with. I assume since there was a court case that it must be in the public domain.

Regards,

John Phillips

Reply to
John Phillips

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