Hagen Brothers farms,Goodrich ND | " For instance, a DC to AC inverter, often uses a stepped square wave. That wave ends up being fuller than a sine wave, so the peak voltage will be lower than 169.696969 and still have the equivalent power. VOMs that are not designed to display true RMS will show a lower voltage than 120 when you test an inverter, but the true power is being generated and capable of use. It is just fooling the voltmeter, because the non RMS meters just divide the measured peak by the 1.41414 constant which is only good for a true sine wave."
Ed, How does inverter power with it's lower peak voltage do operating 120V ac power tool battery chargers ?
I have one of those little lighter plug 100W,modified sine wave inverters that I considered using to power a tool battery charger. When I tested the inverter AC voltage with a cheap digital VOM,it indicated About 115V AC with the engine not running and 12.4 V input. The AC output dropped to an indicated 108VAC with the engine running and DC input at 14 V ??? I dont know if the inverter has some sort of voltage regulator that over compensated for the higher DC input voltage or what to have the AC output voltage indicate a drop on the cheap DVOM ?? Just wondering how a device with a transformer will react to an inverters not quite right power ? |
How does AC power relate to DC?
