Alternety
Like an engineer
In my ongoing project (called a house) I want to add a backup generator. I prewired for this. One subpanel has all the backed up circuits. I am going to used an inverter based Honda generator. It is not designed to be used as an automatic backup generator.
I have available a controller that understands the Honda and sees internal faults (e.g., oil pressure) and does the proper starting and stopping protocols. The problem is a transfer switch. I find only two types. Manual and automatic. The only automatic units I have found want to be the processor that runs the generator. But they don not know the internal details of the chosen generator.
So, what I need is an automatic transfer switch that will take commangd from the generator controller. The controller will sense power loss, wait to be sure it is not just a short term transient problem, start the generator, and when it is up to speed, transfer the suppanel. On grid restore it must transfer power back to the grid and cool down the generator.
OK. Got that. I need a transfer device. My thinking is a 3PDY contactor. A contactor is designed to minimize arcing and handle a bunch of current. I have spent a bunch google hours trying to find a device. There are more annoying terms used for these contractors than I am familiar with. The sites that sell them also tend to assume that if you don't know the manufacturer and part number; you really don't need to buy one from them. My guess is that what I am looking for is a reversing contactor (to get the 3PDT) but I am not sure. The current rating must be for the types of loads expected in a residential subpanel. Not resistive. To minimize cost I have been trying to find a surplus contactor.
Can anyone give me a hand in identifying what device(s) I should be looking for. Manufacturer and part number would be most appreciated. A surplus source. even more. I need 240VAC, 60 or 100A. There seems to be a real price premium to get 100A.
An additional question; what are the regulatory constraints of doing this?
I have available a controller that understands the Honda and sees internal faults (e.g., oil pressure) and does the proper starting and stopping protocols. The problem is a transfer switch. I find only two types. Manual and automatic. The only automatic units I have found want to be the processor that runs the generator. But they don not know the internal details of the chosen generator.
So, what I need is an automatic transfer switch that will take commangd from the generator controller. The controller will sense power loss, wait to be sure it is not just a short term transient problem, start the generator, and when it is up to speed, transfer the suppanel. On grid restore it must transfer power back to the grid and cool down the generator.
OK. Got that. I need a transfer device. My thinking is a 3PDY contactor. A contactor is designed to minimize arcing and handle a bunch of current. I have spent a bunch google hours trying to find a device. There are more annoying terms used for these contractors than I am familiar with. The sites that sell them also tend to assume that if you don't know the manufacturer and part number; you really don't need to buy one from them. My guess is that what I am looking for is a reversing contactor (to get the 3PDT) but I am not sure. The current rating must be for the types of loads expected in a residential subpanel. Not resistive. To minimize cost I have been trying to find a surplus contactor.
Can anyone give me a hand in identifying what device(s) I should be looking for. Manufacturer and part number would be most appreciated. A surplus source. even more. I need 240VAC, 60 or 100A. There seems to be a real price premium to get 100A.
An additional question; what are the regulatory constraints of doing this?