dumbass
100 kW
MY bike has twin 24v brushed motors. Until today I have only run both motors at the same time once. At that time I used 2 24v controllers with 1 throttle. Really didn't like the setup so I installed a single 48v controller and 48v throttle. Today was my first ride with the new setup.
In the shop without the drive chains dis-connected one motor runs at 475rpm and the other runs at 500rpm (no load). The motors are wired in series to the single 48v 50a controller. I use the red controller wire to motor #1 red wire. The black wire of motor #1 is connected to the red wire of motor #2 the black wire from motor #2 is then connected back to the controllers black wire. Like I said in series. So like a string Xmas lights they are sharing the voltage/amperage. I took a test ride of about a block yesterday and everything ran great. So to day I took my first long ride. Had I finised it it would have been about 20 miles. About 6 miles on roadway and 14 miles in the forest preserve.
On my way home motor #1 through a chain. Eack motor has it's own freewheel so if one motor craps out the other can keep going. Nice idea if it only worked. As soon as the one motor had no load the second motor stopped pulling too. It would try to nudge the bike but that was all it could do...just no power. I couldn't move the bike even if it was on the kickstank and no one holding it. It was that bad.
Once I got home I checked the motor RPMs. First the motor without the chain. Holly crap it was running at 950 rpm (sounded really cool though). But the second motor with the chain still connected could only try to move but could not even turn 1 rpm. So I removed the second motor's chain and retested both motors. Motor #1 (the one with the missing chain that was running at 950) now pulled 475rpm again and the second motor (that had the chain) could now pull 500 rpm.
Why? Is there a load balance issue? Both motors have to have the same load to truely share the voltage/current? I am guessing the voltage/current goes to the motor with the least load. So as long as they are both under the same load everything is fine. But when the load shifts to one motor that also shifts the voltage and current. I'm not sure this is a good thing or not. While the chains were bot hconnected it seamed like both motors ran fine together. Not as fast as I had expected though but still Ok. I check both motors after about 10 miles of full speed running and I could hold my hand on them both. they were barely warm (outside temp 70F. Thoughts please........
Bob
In the shop without the drive chains dis-connected one motor runs at 475rpm and the other runs at 500rpm (no load). The motors are wired in series to the single 48v 50a controller. I use the red controller wire to motor #1 red wire. The black wire of motor #1 is connected to the red wire of motor #2 the black wire from motor #2 is then connected back to the controllers black wire. Like I said in series. So like a string Xmas lights they are sharing the voltage/amperage. I took a test ride of about a block yesterday and everything ran great. So to day I took my first long ride. Had I finised it it would have been about 20 miles. About 6 miles on roadway and 14 miles in the forest preserve.
On my way home motor #1 through a chain. Eack motor has it's own freewheel so if one motor craps out the other can keep going. Nice idea if it only worked. As soon as the one motor had no load the second motor stopped pulling too. It would try to nudge the bike but that was all it could do...just no power. I couldn't move the bike even if it was on the kickstank and no one holding it. It was that bad.
Once I got home I checked the motor RPMs. First the motor without the chain. Holly crap it was running at 950 rpm (sounded really cool though). But the second motor with the chain still connected could only try to move but could not even turn 1 rpm. So I removed the second motor's chain and retested both motors. Motor #1 (the one with the missing chain that was running at 950) now pulled 475rpm again and the second motor (that had the chain) could now pull 500 rpm.
Why? Is there a load balance issue? Both motors have to have the same load to truely share the voltage/current? I am guessing the voltage/current goes to the motor with the least load. So as long as they are both under the same load everything is fine. But when the load shifts to one motor that also shifts the voltage and current. I'm not sure this is a good thing or not. While the chains were bot hconnected it seamed like both motors ran fine together. Not as fast as I had expected though but still Ok. I check both motors after about 10 miles of full speed running and I could hold my hand on them both. they were barely warm (outside temp 70F. Thoughts please........
Bob
