Looking for VAX6000 items

Jon Elson elson at pico-systems.com
Wed Jul 14 14:09:29 CDT 2021

On 7/14/21 11:50 AM, Paul Koning via cctalk wrote:
>> On Jul 14, 2021, at 12:33 PM, Guy Sotomayor via cctalk <cctalk at classiccmp.org> wrote:
>> I've found 2 issues w.r.t. "rotary converters".
>> * They *always* consume lots of power regardless of the actual load
> Really?  That seems odd.  A rotary converter is merely a three phase motor with run capacitors.  Just like any other motor, its power demand depends on the applied load.  A normal motor spinning without anything connected to it consumes power to overcome electrical, magnetical, and friction losses, but none of these are particularly large.
Induction motors draw relatively constant CURRENT, but the 
phase angle changes with load.

So, the real power draw  increases with increasing load.

If you assume power equals current times voltage, then you 
get a wrong indication, by neglecting oiwer factor.


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