[amsat-bb] Re: Motor for Yaesu G5500 Azimuth Rotator?

[WA6FWF]

    Just as a follow on, I stuck a watt meter on the controller I have 
(LVB and custom driver board)
2-3 watts idle approx 51 watts turning in AZ or EL, 48 watts stalled in 
one direction 56 watts
stalled the other way in AZ, 56 watts stalled up 50 watts stalled down 
in EL, so slightly less or
slightly more or about the same, no matter how you cut it not enough 
difference to be able to
fuse for it.
    I always thought a timeout in the LVB code might be nice, I'm 
driving but the numbers are not
changing might be nice... but in the meantime the thermals will work..

73
Kevin WA6FWF


On 2/23/2012 4:06 PM, WA6FWF wrote:
> Sorry my mistake, been looking at shaded pole motors for a SB-200 amp 
> and it stuck...
>
>    Yes you are correct AC induction with a capacitor providing the 
> phase shift, when
> I was making a board to connect to a LVB controller to totally do away 
> with the G-5500
> control box I measured the current while running and then measured it 
> locked and to
> my surprise the current was actually less.
>
>   I have had other people tell me that this happens because the cap is 
> too small or
> inefficiencies in the motor itself and it would not act this way in a 
> larger motor.
>
>   Based on the number of burned out motors and transformers and perfectly
> good fuses left over, there is something going on.
>
>   I was originally measuring it to find the values so I could put a 
> PTC in to protect it,
> the current dropping instead of going up ruled that out, so I went 
> with the thermal
> approach instead.
>
> 73
> Kevin WA6FWF
>
>