I have a couple of F3 motors off their frames. How do I connect them to a transformer to test if they are working? Thanks.
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Swap the brush connections to reverse.
Hi ADCX Rob. I successfully hot wired and ran one of the F3 motors using the method below.
(1. Take a jumper wire and connect one brush holder to the metal tab between the brush holders (this is the field tab) 2. attach one test lead to the other brush holder. 3. attach the other test lead to the metal solder tab on the side or the motor, or simply touch it to the metal side of the motor.)
However, the other motor tries to run but only buzzes, vibrates and smokes when wired the same way. I cleaned everything and replaced the brushes. It seems like the gear housing rivets to the field horseshoe are slightly loose.
Thanks
It sounds like the field is not in the circuit, recheck your wiring to be sure it is connected like Rob’s diagram above. Before you put power to the motor, make sure the armature turns freely.
David Johnson. The armature turns free, but I'll check to see if the field is in the circuit. Thank you.
I am working on an F3 with two motors. The E unit is newly rebuilt by a technician. I can only get one motor to run. The other motor has power to it but refuses to engage. I cleaned the armature and replaced the brushes. Still nothing. I want to try and test the motor disconnected from the E unit but I am having difficulty understanding how to bench test the motor. They talk about several test leads from where?? The transformer has power and ground. Where are the other test leads coming from. Sounds like too many test leads and doesn't make sense. Please someone explain all the test leads and how each one hooks up so that I can understand what to do.
The motor has four connection points. They are the two motor brushes and both ends of the field coil. One end of the field coil is usually permanently connected to the motor frame. To test run a motor connect one wire from the transformer to one brush and the other wire from the transformer to the motor frame. A third wire is needed to connect the other brush to the other end of the field coil. The motor should run when power is applied. To reverse the motor's direction reverse the two wires going to the brushes.
See Rob’s drawing above. The two transformer wires go to “hot” and “ground”. The third wire is making the connection by the letter “d” in the word field.
