snarfattack wrote:
Even with the battery disconnected there is still going to be a draw from the converter to power 12v appliances/devices. If you completely turn off the converter, your 12v appliances/devices will run off the battery and you will have full generator power available for your high draw 120v appliances. Most of those high draw appliances only need the extra power during start-up, so PrivatePilots method of putting in a switch to turn off the converter would allow you to turn it off during the startup period, and then turn the converter back on.
If you wanted to get really fancy, you could add an extra relay to the A/C thermostat circuit that would cut power to the converter whenever it decided to turn the A/C on. With some cool electrical engineering you could make the relay only kick off for a minute to allow the A/C to finish starting up. Doing an automatic cut-out for the Microwave would require some EE skill as well.
Actually, it should not take an EE. You can purchase inexpensive current sensing switches at most any store that sells power tools. They are commonly plugged into a wall outlet and then the appliance, like a power saw or sander, is plugged into the device. When the saw cuts on, the device senses the current and provides 120 VAC to to another outlet on the device to turn ON a vacuum to pick up the sawdust.
If such a device were plugged into a microwave outlet and an extension cord run from the same device to a 20 amp Double Throw 120 VAC relay mounted in a box the relay would be moved from a normally closed state to open. If the converter was wired across the contact that is Normally Closed, it would cut off whatever was connected (converter) when the microwave was turned on. Same is true for an A/C except it would need additional wiring.
Why this method? Well, the current sensing circuit is ready made and available - nothing to build. DPDT or SPDT 120 VAC relays are readily available. All additional wiring can be done using conventional wiring boxes and materials.
OK - I'm an EE..... But I can think like a ROF.
