Re: [CAD_CAM_EDM_DRO] Re: Power supply voltage question..Even more info..

Russ Waters wrote:

>First of all, thank you for all the information!
>
>I beleive it isn't a tap, and it's a seperate winding, and is 9.5 vac. The power supply is for three Superior Electric SLO-SYN, #S2000D4-M units.
>
>Also they (Superior) have a surge limited resistor (5 ohms, Dale 7SS5) between the plus out of the bridge and the plus of the cap.... is this necessary, and what is it's function? Will it change the total voltage output?
>
>

5 Ohms? Did you measure that, or read it off the label? It seems like
a very
high value. At 5 Ohms, it will drop 5 Volts for every amp drawn from the
supply. At 10 Amps, it would drop 50 V, and dissipate 500 W! Could it be
0.5 Ohms? That would be more reasonable.

It prevents the rectifier from being destroyed by the inrush surge when
you turn
it on. Maybe it is a negative temperature coefficient (NTC) thermistor,
which
drops resistance to a fraction of an ohm once it heats up.

Jon