|
|
Post by turbokinetic on Jan 21, 2020 4:33:50 GMT
The early FEA and some other GE fridges; as well as Westinghouse and maybe others have three-wire fan motors which will not run without being connected to the compressor motor. These were "two phase" motors and required the compressor motor as a rotary phase converter to power the fan.
I have done some testing and musing about this design here. Maybe interesting.
https://youtu.be/qBwMMRU2GfU
Sincerely,
David
|
|
|
|
Post by Travis on Jan 21, 2020 17:18:46 GMT
That's a very good explanation of this often confusing motor. I will add that the replacement motor GE used for these was a 2 wire motor. I guess they lost interest or enough servicemen got confused by the 2 phase motor. I believe these were also used in the early R12 models GE made. I'll confirm this when I get up close to a 1938 2 dr GE once the weather warms up. The original wiring makes even me worry about trying it.
|
|
|
|
Post by turbokinetic on Jan 21, 2020 17:52:27 GMT
That's a very good explanation of this often confusing motor. I will add that the replacement motor GE used for these was a 2 wire motor. I guess they lost interest or enough servicemen got confused by the 2 phase motor. I believe these were also used in the early R12 models GE made. I'll confirm this when I get up close to a 1938 2 dr GE once the weather warms up. The original wiring makes even me worry about trying it. I understand the worry about the wiring! If that GE needs rewiring, that could be an interesting project for my next visit.  One reason they may have chosen the 2-phase design was for heat limitations of the fan motor. They could make the fan motor operate a lot cooler with 2-phase design then the ones with shaded-pole designs. The winding materials from back in that day weren't good for high temp operation. The cool running 2-phase design allowed for a compact fan motor which would not block airflow due to its size, and which would operate cool enough to have a long life. Once the winding material quality was up, the simpler shaded-pole design won out due to cost considerations, most likely. |
|
|
|
Post by don on Jan 21, 2020 23:06:24 GMT
|
|
|
|
Post by coldspaces on Jan 22, 2020 0:39:53 GMT
Yes that was a good video on those motors. My 1940 Hotpoint flattop had a 2 phase motor.
|
|
|
|
Post by turbokinetic on Jan 22, 2020 3:38:35 GMT
Thanks guys. Good to see the GE document on the testing of the motor. I know the Westinghouse motor will run with a 1uF cap but not at full speed. Need to test a GE one. |
|
|
|
Post by stlvortac on Feb 6, 2020 15:36:53 GMT
Thanks guys. Good to see the GE document on the testing of the motor. I know the Westinghouse motor will run with a 1uF cap but not at full speed. Need to test a GE one. Thanks for sharing! I had to teach myself that concept when I rewired my 39 flat top. Unfortunately the fan motor wires were so brittle I wasn’t able to reuse it. In fact it literally crumbled in my hand. Issue being it’s internally wired and requires machineing to remove the motor cap. I believe blackhorse or Travis detailed the rewire process but it was a bit above my capabilities at the time. When I wired my flat top I left the start ‘phase’ terminated by the replacement fan for its eventual return. When I first purchased the fridge the original 2 phase motor was slow to start, eventually I found out it was about of oil. The GE manual said to fill with straight 10 weight motor oil. Unable to find any I got 3 in 1 20w electric motor oil. Hopefully the bearings are still ok. If you’d like to use it as a guinea pig I’d be more than happy to ship it to you and cover the cost! |
|
|
|
Post by coldspaces on Feb 6, 2020 18:16:06 GMT
Thanks guys. Good to see the GE document on the testing of the motor. I know the Westinghouse motor will run with a 1uF cap but not at full speed. Need to test a GE one. Thanks for sharing! I had to teach myself that concept when I rewired my 39 flat top. Unfortunately the fan motor wires were so brittle I wasn’t able to reuse it. In fact it literally crumbled in my hand. Issue being it’s internally wired and requires machineing to remove the motor cap. I believe blackhorse or Travis detailed the rewire process but it was a bit above my capabilities at the time. When I wired my flat top I left the start ‘phase’ terminated by the replacement fan for its eventual return. When I first purchased the fridge the original 2 phase motor was slow to start, eventually I found out it was about of oil. The GE manual said to fill with straight 10 weight motor oil. Unable to find any I got 3 in 1 20w electric motor oil. Hopefully the bearings are still ok. If you’d like to use it as a guinea pig I’d be more than happy to ship it to you and cover the cost! I have one I saved and may try to rewind it some day. I opened one other one before and found the paper insulation around the windings was so bad I couldn't attach new leads to it. Blackhorse is the one who detailed how to disassemble the motor to get the stator out. |
|
|
|
Post by turbokinetic on Feb 6, 2020 21:06:08 GMT
Thanks for sharing! I had to teach myself that concept when I rewired my 39 flat top. Unfortunately the fan motor wires were so brittle I wasn’t able to reuse it. In fact it literally crumbled in my hand. Issue being it’s internally wired and requires machineing to remove the motor cap. I believe blackhorse or Travis detailed the rewire process but it was a bit above my capabilities at the time. When I wired my flat top I left the start ‘phase’ terminated by the replacement fan for its eventual return. When I first purchased the fridge the original 2 phase motor was slow to start, eventually I found out it was about of oil. The GE manual said to fill with straight 10 weight motor oil. Unable to find any I got 3 in 1 20w electric motor oil. Hopefully the bearings are still ok. If you’d like to use it as a guinea pig I’d be more than happy to ship it to you and cover the cost! I have one I saved and may try to rewind it some day. I opened one other one before and found the paper insulation around the windings was so bad I couldn't attach new leads to it. Blackhorse is the one who detailed how to disassemble the motor to get the stator out. Thanks for the good discussion on these motors. I would love to see pictures of GE's 2-phase design. I've only opened the Westinghouse ones. If the link to Blackhouse's write up could be posted I would be most appreciative! |
|
|
|
Post by CCL2F2 on Feb 6, 2020 21:19:12 GMT
|
|
|
|
Post by turbokinetic on Feb 7, 2020 1:06:15 GMT
Thanks, I appreciate that. It's always good to keep them oiled up!
|
|
