Grundig PAPST motor...

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I think it is similar to TK46, Papst types part number from memory is 788-102.00. Three wires, Yellow and Green is 220V connection and a capacitor of either 1.55uF or 2.0uF, (depends what your mains frequency is) at 380v AC Type X or Y connects between the Blue and the Yellow.
I saw one of these, TK-46, many years ago, as I was the last Regional Servicentre in the UK before I retired.
I tried googling for Papst synchronous motor
Not much success.
I'd guess you have a syncronous motor that locks to mains frequency. That is what the reel to reel required for the tape drive motor.
It needs a two phase supply. That's what the capacitor does.
It can have any of a variety of speeds depending on how many poles are built into the construction.
50Hz 2pole gives 1500rpm. That the fastest you can get.
4pole, 8pole, 12pole would run at a fraction of that 1500rpm.
I don't know if 6pole exists, but you can get 16pole (187.5rpm).
8pole (375rpm) was common for TT drive, requiring ~11:1 reduction for 33.33 LP speed. 2% of slip gets very close to LP speed. I don't have data for the expected slip % for a rubber belt drive.

could you give us more tech info on synchrous motors?
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Thank you both for reply, yes there us very little technical info on Papst motors...The motor type is 7882 - 036. Other numbers are KM20.50-4/8-140 D , year 22.8.1960... I checked wires going to motor, there are 6 wires, Yellow, Red, Green, Red/Black, Yellow/Black and Green/Black...Would this help anything Jon? Would be good if I could find schematic, not easy too...
I did some measurement on wires, resistance between any solid color, Red/Green/Yellow is 52 ohms and between mixed colors RedBlack/GreenBlack/YellowBlack is 32 ohms...does it say anything? Would anyone be able to sketch how to connect it to supply for some test and where goes capacitor?
I have two identical motors actually (type 7882-036), one made on 22.08.1960, the other one 19.12.1960; Serial number on first is 2299647, on second 2516190...the difference is 216,543 pieces...PAPST was very busy at the time, even if we take into account that they were exporting to the time, or maybe because of that...just little statistics while trying to find some diagram...
Here is diagram which I think suit motor that I have, so stoN_COLD was right, it is 2 speed and use 165 and 117 volts. If I am correct switch S2 switches to ground or neutral...Just do not understand that 20 ohm resistor and capacitor in series...wires from left are Red/Black, Red, Green, Green/Black, Yellow/Black, Yellow...


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