For anyone who has seen Michaels kits, they are top notch. The motors he uses are solid too. They are somewhat large compared to a 3220, but considering they cost half as much, it's worth the lesser cost. Also they are solidly built and strong motors. I own 2 of them. The first one I purchased about a year ago and other than a hall failure which was 100% my fault, the motor has given me no trouble at all. I run it at about 3500 watts and my scooter tops out at about 50mph. I can easily out accelerate most cars despite my scooter weighing 120 pounds while carrying my lard butt 240 pounds. I've wanted to play with WYE/DELTA switching for a good while now and haven't had the time until now to do it. with the purchase of my second big block, I prepared in advance to be ready to convert it to WYE/DELTA switching before it ever got it installed in anything.
Eventually it will go in this moped. It needs some work still, but is pretty close to rideable.
Initially I will be running at 82 volts since I already have the battery pack built for that voltage, but eventually it will be running at 130 volts. On to the motor rebuild...
The big block is capable of running at well over 3000 watts. Some people report that they run them at 5000 watts. I'm going to use that 5000 watts as my starting point and see how far I can push it. The first thing I did was get the end plates opened up so I can push air through the motor to keep it running cool. I'm expecting that with a fan or blower, I can run the motor at 5000 watts with no overheating issues and probably a lot more.
Some pictures of the motor as a I received it from LR. He normally cuts off the fan shaft and paints it black, so this is going to look a bit different than what most people are used to seeing. Some of you will notice the ratings lazered into the front of the motor. The Chinese to get around our import laws under rate the motors by quite a lot. Ignore the information on the motor...it's waaaaay wrong.
This is the opened up end plates.
Once I had tested the motor and it was obviously in good shape, then it was time to start taking it apart. Once I got at the windings, this is how I found all the phase wires were connected to the windings. This is the WYE connection. Somehow they melted the copper wire ends together. There's no way that connection is ever going to fail. Obviously I had to cut that blob of copper off of there to separate the phase wires.
This is the phase ends after I tinned them. I then figured out which end was the other end of each phase and temporarily labeled them with some masking tape.
I then reconnected all the phase ends to colored 10awg wires with wire crimps and then soldered everything together. The connections should easily handle the maximum capabilities of the phase wires.
The original phase ends, I labeled as B1, Y1 and G1 and the secondary ends I labeled as B2, Y2 and G2. This is the 6 phase ends with 2 layers of heat shrink on each connection.
The wires needed to be secured and bound down inside the motor so several zip ties made quick work of that. I'll get some cotton thread later to tie it all together to make it all permanent. Zip ties tend to melt when they get too warm.
I've looked at several peoples schematics for how to set up a relay for WYE/DELTA switching, but none of them made clear sense to me so I drew my own. It was obvious what needed to be done so I just figured it out for myself. In the relaxed state the relay needed to connect the B2, Y2 and G2 wires together and in the activated state, they need to be connected in Delta. This schematic is the final result.
I guess I should have taken a few more pictures along the way, but you get the idea. The cable that comes on these motors is about 3 feet long. I used sections of that cable to make all the connections you see here. Once I had everything bound together and brought out of the motor case, I then added 2 more layers of heat shrink around all the wires where they come out of the motor case so that they couldn't get scuffed or worn through by vibration or motion. I zip tied all the wires together where they exit the motor so that nothing can move separate from anything else and become fatigued or break. Every phase end terminates in a male 5.5mm bullet which are good for 100 amps or so...plenty for this motor. This allows me to disconnect the relay from the motor and manual connect the motor in WYE or delta if needed. This is the completed motor and relay set up.
A side note about Grinfineon controllers...
The grinfineon controller I was using for testing is the older version (7240-NC) and not the best thing there is. Its eRPM is quite low and only really effective for hub motors. They are very basic controllers, but better than your Chinese trapezoidal controllers. At least it can be sinusoidal. IMHO, the most redeeming value it has is that it uses IRF4110 mosfets. Otherwise, they are not that great. They can run sensorless or sensored which sounds great. Since the controller has to "sense" the halls, if there is any kind of an issue, it defaults to sensorless mode. When you are trying to figure out the correct hall to phase pairing, this controller is more of a hindrance than a help. You can't be totally sure you have the correct pairing since if the controller finds anything wrong, it just defaults to sensorless. When I first got everything wired up for WYE/DELTA switching, I made no mistakes. Everything was wired correctly and the controller would not see the halls. As a result I fiddled around for probably an hour trying to "find" the correct pairing and eventually ended up back at the original combination. I prefer a controller that simply doesn't work when the phase and hall pairing is incorrect. This controller really needs a switch that hard wires it into sensored or sensorless modes. There's two versions of the Grinfineon. The older 7240-NC and the newer 7240-GR. All the videos are made with the older version which has a lower eRPM than the newer version. Anyway, the older version is really only effective for hub motors. In the videos you will see that the controller loses sync at different times. With halls at 48 volts the controller could spin up the big block motor most of the time to full RPMs. Without halls, it can get maybe 40% throttle in WYE. In delta, the controller can deal with 40% throttle with halls before losing sync. I just purchased one of the more expensive versions so I have nothing to say about it...yet, but the older/cheaper version is inadequate for anything not a hub motor. Supposedly the newer version is good for 28,000 eRPM. For anyone looking for a basic and cheap controller, don't buy the older/cheaper version (7240-NC). You will be disappointed. I have received the newer version and took it apart. The battery and phase wires on the old and new versions are 14 awg nylon insulated. In fact all the wiring is nylon insulated. The insulation is not low temperature, but it can melt. I have a couple of cheap Chinese controllers of similar ratings and they have teflon coated wiring. IMHO, all major wiring ought to be teflon or silicon. Even though 14 awg is probably enough for a 40 amp controller, I would still make it thicker. As a result I replaced all the battery and phase wires with 12 awg silicon in the new controller. I wanted to use 10 awg, but the solder holes in the board were too small and 12 awg was all the larger I could go. For anyone looking for a cheap sinusoidal controller, don't get the cheaper version. It's just not worth it. I'll add another post about the 7240-GR once I have tried it out.
Here's several videos on the project.
This one is running sensorless at 48 volts.
https://www.youtube.com/watch?v=m3rZCvA ... UWoxep2mrR
This is running sensored at 48 volts.
https://www.youtube.com/watch?v=hB-Pt67 ... UWoxep2mrR
Since I had an 82 volt pack I built for the moped, I hooked it up too. This video was made without ever trying out the controller in advance. I started up the camera and tried it out. The Grinfineon is rated to 88 volts so it wasn't going to be an issue.
https://www.youtube.com/watch?v=B0bx7uY ... R&index=13