Quote:
Originally Posted by TheStebes
Thanks for the reply.
This image helped clear things up: http://www.marxrv.com/12volt/inv3.gif
Basically, I'll keep appliances like the microwave/ac unit on separate breakers which are only tied to the AC input from the generator. . . .
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Quote:
Originally Posted by putterspitt
To the OP; I dont know how you will be able to separate the different circuits within the same breaker box to keep from crossing power sources. I suggest you run a single breaker box, with a single inlet, and be able to plug your various power sources into that inlet ONE at a time. From there, only use the appliances that you know the particular power source will handle.
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The drawing linked to was for 120 volts single-phase. It was drawn as a special box with a split main leg. By using a common 240-volt panel for a 120-volt system, breakers on one 120-volt hot leg could be wired to the shore/genny input, and feed the charger/transfer switch input of the inverter/charger plus heavy loads like the air conditioner. The other set of breakers would be the critical loads side fed from the inverter output. The inverter output would feed back through one large breaker on that leg as the sub-master. The two legs would not be tied together, except through the inverter when on live shore/genny power.
A more common set up I've seen in commercial buildings and also in RVs is to have two breaker panels - one street panel plus an 'emergency' panel for protected loads. Using the split 240-volt arrangement instead of another panel means you should have optional connector buss bars installed in the panel as shown in the drawing in the link. One bar is bonded to the enclosure for the safety grounds, another one isolated from ground ties together the street-fed neutrals, and a third isolated from the other two for the inverter-fed neutrals. The grounds can be tied together, but the neutrals should not be bonded to ground except at the sources: the campground/house entry point, inside the genny, and in the internal inverter transfer switch. Get an RV-model inverter with a 3-pole internal transfer switch for hot, neutral, and ground; not a residential model with two-pole transfer that only switches hot and neutral.
Of course, the KISS method of having the breaker box fed from a plug that is moved to different outlets fed by street, genny, or inverter avoids most problems, outside of remembering not to run air conditioning or other heavy loads off of the inverter. But you lose the automatic power failure transfer feature for critical loads such as medical equipment, refrigeration, etc. It may be OK if the AC quits if the genny runs out of fuel, but your companion(s) may get testy if the TV also quits during a favorite show while you are out wrestling with the tanks. The same would hold true of a power failure while sleeping with a "hose to the nose."