The Lionel San Francisco Trolley 6-18404 is described as having an AC/DC wound motor ? Does this trolley work on both AC and DC ? It has an open frame type motor.
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@Überstationmeister posted:Yes.
How does it work on DC ? Is there a switch ?
Put it on the track and apply your choice of AC or DC- the motor is universal. It will reverse direction when the bumper impacts a track bumper or other convenient object.
Note that DC polarity does not matter and that track power interruption will have no effect on the direction. It is possible to re-wire the motor with a bridge rectifier so that that the motor will respond to DC polarity.
@Überstationmeister posted:Put it on the track and apply your choice of AC or DC- the motor is universal. It will reverse direction when the bumper impacts a track bumper or other convenient object.
Note that DC polarity does not matter and that track power interruption will have no effect on the direction.
Thanks for the information. Does the trolley reverse when the DC polarity is reversed ?
@Überstationmeister posted:DC polarity does not matter as wired from the factory. It is possible to re-wire the motor with a bridge rectifier so that that the motor will respond to DC polarity.
Thanks again. I getting a little smarter on this subject thanks to your helpfulness !! My understanding at the moment is that the post war open frame motors can run on both AC and DC equally well abet whistle/bell issues. If DC polarity is reversed, the motor will continue to run in the same directions since both the armature and field are reversed. If just the field or armature is reversed the motor will reverse. I would think adding a bridge rectifier would be the same as running on DC and would not reverse the motor. Modern engines use DC can motors. Adding a bridge rectifier to the DC can motors makes them work on AC. You can eliminate the bridge rectifier feeding DC can motors and run them directly off DC.
@shorling posted:I would think adding a bridge rectifier would be the same as running on DC and would not reverse the motor.
If you isolate either the armature OR the field and run one of them with a FWB full wave bridge rectifier, then it will reverse with a change of DC polarity on the track. The armature & field still need to be in series... if they are shunted, you will draw too much current. I've done this, but the performance isn't spectacular.
@ADCX Rob posted:If you isolate either the armature OR the field and run one of them with a FWB full wave bridge rectifier, then it will reverse with a change of DC polarity on the track. The armature & field still need to be in series... if they are shunted, you will draw too much current. I've done this, but the performance isn't spectacular.
Thanks for the info !! I'm getting an education. What if I run on DC and keep the windings in series but reverse the field wires. Will the motor reverse when I change track DC polarity ?
@shorling posted:What if I run on DC and keep the windings in series but reverse the field wires. Will the motor reverse when I change track DC polarity ?
No, you will get one direction operation only without the use of a rectifier to keep either the armature or field oriented in one direction in relation to the switching orientation in the other.
@ADCX Rob posted:No, you will get one direction operation only without the use of a rectifier to keep either the armature or field oriented in one direction in relation to the switching orientation in the other.
Can you draw me a wiring diagram ?
@ADCX Rob posted:
Thanks, problem solved !
