> From: Paul Goyette <paul@whooppee.com> > > Arild will probably jump in on this, but if I remember correctly, the > big issue is when you're trying to run "inductive loads" on the wrong > flavor of electricity. Mostly, this means "things with motors", and > includes your laundry machines, air conditioning compressors, and the > refrigerator/freezer compressors. Most electronics simply convert > incoming juice to DC anyway, and will tolerate wrong-Hz with little or > no ill effect. Paul has it pretty close to correct. Inductive loads and iron cored transformer devices tend to resonate at one frequency only. Inductive motors and laminated iron core transformer stuff designed for 60Hz tend to run hot on 50Hz due to eddy current and motors lose about 17% on 50HZ compared to 60HZ. Switch mode power supply equipment does not mind because it chops up the incoming line frequency before converting it at high frequency to whatever power is required. As a general guide anything with heavy iron cores may be frequency dependent but switch mode power supply equipment tend to be independent. Motors run slow if shore power is at a lower frequency so they tend to need higher starting current which results in heat generation and premature failure. Resistive loads do not care. This includes coffee makers, toasters, counter top cooking appliances and of course all light bulbs Several charger manufactures now make universal input products that functions over a range pf 90V to 265V at any frequency. Best approach would be to install such chargers to charge the battery from available dock power then use the existing inverter to deliver 120V @ 60hZ. Totally disconnect shore power from the inverter unless you know the voltage and frequency is compatible. With a large enough battery bank and enough inverter capacity you could use one A/C to cool down a staterooom overnight. Arild