[Elecraft] KPA1500 240v (was: Another really good reason to come to the Visailia DX convention this weekend...)

[Josh Fiden]

That may not be true for the KPA1500. It's pretty common now, especially 
in higher power switchers, to include power factor correction (PFC). 
Instead of only charging bulk caps at AC peaks when rectifiers are 
forward biased, the rectified incoming line hits a boost converter which 
smooths out the cap charging rate.

For example, the Meanwell RSP-3000 48V 62A supply, includes PFC and 
claims power factor > 0.95. Without PFC, might be PF=0.6 and certainly 
operate as you describe with high current peaks, big IR drop & I2R power 
losses.

73,
Josh W6XU

On 4/24/2017 8:51 PM, Jim Brown wrote:
> ...is not sinusoidal, but rather pulses that charge the filter caps at 
> the peaks of each cycle. So the drop in the wire is even greater than 
> Ohm's law applied to a sine wave would predict.