Lionel ZW voltage

I've acquired a Lionel ZW transformer and checking the voltage, I find that the 4 terminals all have a high voltage of 21.4. What surprises me
is that in the off positon, A and D run about 3 volts and B and C about 1.5. I would think that the 4 terminals should read 0 volts in the off postion. Otherwise, could not the windings of locomotive motors burn out?
I would appreciate knowing whether my ZW is defective or typical. Thanks, Warren
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Your ZW has problems. In the "Off" position, the moving contacts should be resting on an insulating pad and not contacting the transformer secondary winding. The B and C circuits are a direct path from the moving contacts to the respective terminals. If you see any voltage, it means the contacts are probably not moving off the windings. This could be due to broken or worn carbon contact rollers, so the metal frame is rubbing on and possibly cutting the copper windings, or it could be due to slop where the moving contact arms are attached to the control shafts so the contact arms are not moving all the way to the off position. These same problems could be causing the voltage that you are seeing on the A and D terminals, but in addition, these circuits have the whistle controls, which include a 5 volt compensating winding to provide additional voltage to the train when the whistle is activated. The whistle control contacts may be bent or not returning to the normal position, providing voltage from the compensating winding to the A and D terminals. Unplug the transformer and open the case visually inspect these areas.
You may want to look at the origianl Lionel Service Manual sheets for the ZW which are on line at: http://pictures.olsenstoy.com/searchcd31.htm?itmg1
Good luck, Geezer
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I find

surprises me

C about

the off

burn
typical.
It would help to know if you're talking about the new ZW, with the external power 'bricks', or the older self contained unit.
Len
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