Re: Bad Boy "Plus" Opportunity Charger

[Lee Hart <leeahart@earthlink.net>]

Mike Chancey wrote:
> I have been told since the ammeter is of the "moving metal" type it
> should be true RMS.  Does this make sense?

No. The most common types of analog movements are the D'Arsenval (fixed
magnet, moving coil), and iron vane (wound field coil, moving iron
rotor). Both of these are average-reading meters, not true rms.

True-rms analog meters are thermocouple meters; they have a little
resistor as the sensing element, and thermocouples to measure its
temperature rise.
> would there be any advantage to using a different transformer rating,
> or would the 24 volt unit still be appropriate?

Transformers have inductance, but it is not specified on their data
sheet, nor can you calculate it from their voltage and current ratings
-- you have to measure it. If you don't happen to have an inductance
meter, then connect the winding to an AC source and measure the voltage
and current. Inductance can be calculated from:

    L = V / 2 pi F I    where L = inductance, in henries
                              V = AC voltage across inductor, in volts
                              I = AC current through inductor, in amps
                              F = frequency, in Hertz
                             pi = 3.14159...
-- 
Lee A. Hart                     Ring the bells that still can ring
4209 France Ave. N.             Forget your perfect offering
Robbinsdale, MN 55422 USA       There is a crack in everything
(612) 533-3226                  That's how the light gets in
<leeahart@earthlink.net>                Leonard Cohen