Re: Charger selection (was: Down side...)

[Thomas Shay <tshay@ix.netcom.com>]

Hanson, Mark E (IndSys, SalemVA) wrote:

> Standard power factor for a non-PFC charger or power supply is .63, which
> means that if 1800W is attainable from a 15amp 120V line with PFC (ferro or
> solid state >.95) then only 15 x .63 = 9.45A or 1134 watts can be had
> without smoking wires/connectors or tripping breakers.

   But, chargers don't have a standard power factor.  Power factor can
varyconsiderably depending on design details and operating conditions.  My
simple
charger operates at about .75 power factor at maximum output and the
power factor decreases as output is reduced.  The power factor is about
.10 when the output current approaches zero.

  A poor power factor does not reduce the amperes that can be drawn.
It reduces the power instead.  At .63 pf, for example, the power output
at 15 amps and 120 volts would be 1134 watts.

Tom Shay