DELARANEWS

Tech

An Automatic Transfer Switch

Mike, W8MDC I completed my electrical project over the weekend, using the other transfer switch I bought. I now have a dedicated GFCI protected outlet for a second (backup) sump pump, running off the transfer switch, which is fed by both the main circuit breaker panel and a 110 volt inlet. The inlet is connected to an inverter and battery bank. This will allow me to replace an old 12 volt sump pump, which ran forever because it didn't have enough umph to push the water up 10 feet and outside. I can put in a full sized pump, running off this power protected circuit. One odd thing however... The transfer switch I used (just like the once pictured here) expects the presence of the generator power to throw the switch. In my case, the inverter will always be on. I wanted it to switch only when the main power went out. So I connected the inverter to "shore power input", and the main power to the generator input. That means the internal relay is always engaged with main power on instead of only when the 'generator' power is on. One more thing I had to keep in mind. You can't feed a GFCI outlet by using an inverter's (or generator's) GFCI outlet as the source. The downsteam GFCI outlet will trip. You have to use an inverter or generator with a 'floating neutral' (not neutral bonded to ground). It is also why you want a proper DPDT transfer switch to switch both the hot and the neutrals. PS: The pictured transfer switch is still available to a good home. It is new/unused. If no takers, I'll try to re-sell on ebay.
DELARANews

Tech

An Automatic Transfer Switch

Mike, W8MDC I completed my electrical project over the weekend, using the other transfer switch I bought. I now have a dedicated GFCI protected outlet for a second (backup) sump pump, running off the transfer switch, which is fed by both the main circuit breaker panel and a 110 volt inlet. The inlet is connected to an inverter and battery bank. This will allow me to replace an old 12 volt sump pump, which ran forever because it didn't have enough umph to push the water up 10 feet and outside. I can put in a full sized pump, running off this power protected circuit. One odd thing however... The transfer switch I used (just like the once pictured here) expects the presence of the generator power to throw the switch. In my case, the inverter will always be on. I wanted it to switch only when the main power went out. So I connected the inverter to "shore power input", and the main power to the generator input. That means the internal relay is always engaged with main power on instead of only when the 'generator' power is on. One more thing I had to keep in mind. You can't feed a GFCI outlet by using an inverter's (or generator's) GFCI outlet as the source. The downsteam GFCI outlet will trip. You have to use an inverter or generator with a 'floating neutral' (not neutral bonded to ground). It is also why you want a proper DPDT transfer switch to switch both the hot and the neutrals. PS: The pictured transfer switch is still available to a good home. It is new/unused. If no takers, I'll try to re-sell on ebay.