Hack but ....

[GoldDigger]

The concern is that someone could connect and run the generator without pulling your fuses.

A proper (safe and legal) interlock makes it physically impossible to have the generator output conductors and the service conductors ever connected to each other, ad not depend on intentional actions.

Your solution depends on operation and intervention by someone who knows the procedure.

My idea of a cheap lockout for generator use (just for powering a 240V well pump, with other loads being portable cord connected) is to feed the pump through a fused disconnect with a pull out block and also connect the generator inlet to the pump through an identical disconnect. I then removed one of the fuse blocks to a distant storage space (I am too much of a packrat to throw it away). The result is that the one available block will either connect POCO or connect the generator.

 

[kwired]

The concern is that someone could connect and run the generator without pulling your fuses.

A proper (safe and legal) interlock makes it physically impossible to have the generator output conductors and the service conductors ever connected to each other, ad not depend on intentional actions.

Your solution depends on operation and intervention by someone who knows the procedure.

Many listed interlock kits are easy to intentionally defeat, they do present enough interference that you must at least think about what you are doing though.

 

[kwired]

My idea of a cheap lockout for generator use (just for powering a 240V well pump, with other loads being portable cord connected) is to feed the pump through a fused disconnect with a pull out block and also connect the generator inlet to the pump through an identical disconnect. I then removed one of the fuse blocks to a distant storage space (I am too much of a packrat to throw it away). The result is that the one available block will either connect POCO or connect the generator.

I have used DPDT relay with 240 volt coil in the well supply circuit.

Well connects to common terminals, normal power to NC contacts, standby power to NO contacts along with the contactor coil. It automatically transfers to standby source whenever standby voltage is present.

Done this at a livestock facility - if they lose power they can manually open curtains for ventilation, they can manually supply feed if needed, water is critical, and only thing they really cared about needing power for should utility fail.

 

[gar]

190423-0832 EDT

LarryFine:

This thread started out by oldsparky52 describing what he does for himself, and he is apparently an electrician (electrical contractor). My comments have been directed to him, not my nextdoor neighbor. My neighbors are mostly clueless with respect to electrical things, and no way would I ever suggest they do what I do.

All my neighbors could afford to have, and should have, an automatic backup generator, but probably not more than 3% have one or any generator. One, a DTE person, has a portable and a manual transfer switch. He is the 3%.

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