[Info-vax] OT: the Daily WTF for today is a VAX/VMS story

[Johnny Billquist]

On 2016-02-14 23:57, William Pechter wrote:
> In article <n9quvs$l1l$1 at Iltempo.Update.UU.SE>,
> Johnny Billquist  <bqt at softjar.se> wrote:
>>
>> So we are down to a separate starter motor? Fair enough, if you have
>> that then yes, you can definitely do different tricks. But then you no
>> longer have that simple AC motor.
>>
>> And I can tell you that the RP06 have no such thing. There is just one
>> electric motor, and it's a DC one.
>>
>> 	Johnny
>>
>> --
>> Johnny Billquist                  || "I'm on a bus
>>                                    ||  on a psychedelic trip
>> email: bqt at softjar.se             ||  Reading murder books
>> pdp is alive!                     ||  tryin' to stay hip" - B. Idol
>
>
> What the.  IIRC, RP06's have the same 220 AC motor that I remember changing.
> IIRC the same motor's in either my washing machine (20 years old or so)
> or my electric clothes drier... Big heavy and 220 volt.
>
> No way that's a DC motor.  Two phase -- yes.

Just read through the service manual.
Check 
http://www.mirrorservice.org/sites/www.bitsavers.org/pdf/dec/disc/rp04_rp05_rp06/RP05_06_DriveMaintMan_Dec75.pdf, 
page 3-102 (or page 90). There you have +50V to the motor control.
I can't find any other motor feed. However, you got me wondering some 
more, since you are supposed to have a different motor for 50Hz and 60Hz 
operation, which would suggest that it should be AC. But power is wired 
either wye or delta, depending on what your power source is.

It's getting too late, and I really should stop reading old manuals. 
I'll accept that I remember wrong, and that it's an AC motor after all. 
But not a synchronous one...

	Johnny



-- 
Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at softjar.se             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol