How Big a Gen to Run a Converter? Some Info.
EDIT: some of my earlier posts in this thread have the wrong idea. As more info came in later, things got less confusing--sort of! :) --------------------- Another look at this topic. It is n...
Forum Discussion
With AC, volts*amps does not give watts. It gives volt-amps, which may or may not be the same as the watts. Volt-amps and watts are the same only when the power factor is 1. The problem we have with small generators and converters is that the converter companies give their specs in watts, the more favorable figure for them, while the generator manufacturers spec the volt-amps, the more favorable figure for them. With the typical 0.7 power factor of a converter, the VA is 43% higher than the watts.
When measuring voltage and current of a converter input, you must use RMS meters, especially with the current which is very non-sinusoidal. The kill-a-watt does give RMS readings. Besides the volts, amps, and watts, the kill-a-watt gives VA and pf readings directly.
When measuring voltage and current of a converter input, you must use RMS meters, especially with the current which is very non-sinusoidal. The kill-a-watt does give RMS readings. Besides the volts, amps, and watts, the kill-a-watt gives VA and pf readings directly.
ktmrfs wrote:This statement nails it for RV generator use. Power factor correction for motors is simple. For power supplies it's complicated and expensive. Like so many other things it's being driven into integrated circuits and will eventually become a standard feature that doesn't add much cost.
Granted many generator users are driving close to resistive loads, most power tools, even an AC has a PF close enough to 1 to not be an issue. But microwaves and converters are terrible.
