Bgt2u
Member
Just a quick question....Will a BLDC, or Boma 72v 3000w motor run on 48v? I know it would obviously be under volted, but would it work?
Motor voltage
- Thread starter Bgt2u
- Start date
it should, yes
but it will NOT provide 3kW of course (at best 2000 more likely 1600-1800 really)
why you ask?
'sid
but it will NOT provide 3kW of course (at best 2000 more likely 1600-1800 really)
why you ask?
'sid
Bgt2u
Member
I was thinking of eventually moving up to a 72v system. Since finances are always a problem, l was wondering if l could just replace the 48v motors, with the 72v, and ride around like that, (until l could afford a 72v batpack). I know the controllers will work, (even the ones that l have now), because the required amps for 72v 3000w, is 41.67a. So l was just questioning what would happen if l just changed out the motors (for now), and if it would still perform about the same as it did with the 48v motors.
I wonder why you want to swap the parts that are working well instead of the ones that are holding you back first..
just to have a system that's a slightly bit worse than before...
Rather swap to the better controllers now
(if you get the settable type you can run them @48V now and 72V later)
that way you can have a BETTER running setup today and upgrade later to get even more oomph
'sid
just to have a system that's a slightly bit worse than before...
Rather swap to the better controllers now
(if you get the settable type you can run them @48V now and 72V later)
that way you can have a BETTER running setup today and upgrade later to get even more oomph
'sid
Bgt2u
Member
I ordered two Kelly controllers (55a, max130, 48-72v), so that actually has been taken care of. So, even after l install them, the most expensive thing would be the batpack upgrade. Since l cannot afford that for a while, do you think the two 3000w 72v motors, and the Kelly controllers would work (almost) as well as the two 1800w 48v motors, and crappy controllers did?
hm tough question..
I'd say the 72V motors on 48V should behave a bit more sluggish than the 48V motors
Then again the cheap controllers ont he other hand weren't exactly up to par with the 48V motors anyways.. so those might have been less snappy than they could've been in the first place.
upping A, reducing B.. the sum might be identical *shrugs*
Sorry.. can't make a sound prediction here.
I cannot rule out, that the motors have a 60V startup threshhold even
(I highly doubt it.. hence my "should work" above)
but at worst you have the motors sitting on a shelf waiting for the batteries, no?
And you'd still end up with the slightly snappier toy (once the kellys are mounted)
'sid
I'd say the 72V motors on 48V should behave a bit more sluggish than the 48V motors
Then again the cheap controllers ont he other hand weren't exactly up to par with the 48V motors anyways.. so those might have been less snappy than they could've been in the first place.
upping A, reducing B.. the sum might be identical *shrugs*
Sorry.. can't make a sound prediction here.
I cannot rule out, that the motors have a 60V startup threshhold even
(I highly doubt it.. hence my "should work" above)
but at worst you have the motors sitting on a shelf waiting for the batteries, no?
And you'd still end up with the slightly snappier toy (once the kellys are mounted)
'sid
Bgt2u
Member
Yes, l figured it would be a tossup, with (in theory) no clear winner, and putting them on the shelf is always an option. The whole reason for me upgrading motors would be for more torque, so l figured l'd go with the highest voltage... the 72v option. However, after comparing Boma motors 60v/72v, l have come up with some questions. It is my understanding that the more amps that are applied, the more torque a motor would produce. The (claimed) motor specs in question are: 60v, 3000w, 50a, @4800rpm, VS: 72v, 3000w, 41.67a, @6000rpm. The 60v motor requires more amps, but the 72v motor, has a higher rpm, so gearing could be reduced slightly, upping the torque a bit. Given this information, which motor setup do you think would be best for my application?
again.. nt so easy..
while there is the rule of thumb, that volts make rpms and amps make torque,
that's only half true
without the exact torque diagram (for both motors) for comparison
you simply can't tell.
But in the end the simple fact remains,
that no matter what with two similar output motors (power not torque here)
you can always gear them so that they have the exact same torque
'sid
while there is the rule of thumb, that volts make rpms and amps make torque,
that's only half true
without the exact torque diagram (for both motors) for comparison
you simply can't tell.
But in the end the simple fact remains,
that no matter what with two similar output motors (power not torque here)
you can always gear them so that they have the exact same torque
'sid
Bgt2u
Member
Very true, so once again, there is no clear winner l suppose. The 72v setup is only slightly more expensive than the 60v, so, if it were you, what would you go with? I started out with a 48v setup, because l knew basically nothing about EVs, motors, controllers, etc. Don't get me wrong, my 48v setup works well, however, since l have decided to go for maximum performance, (and the Kelly controllers will handle it). This time, l want to think everything totally through, and set it up the best that is possible. I also still will be using two batpacks (one for each controller/motor), so that l have the correct continuous discharge rate for each motor, and don't overstress the batpacks. I know these little Boma motors can only put out so much power, and torque, so l am not expecting a "rocket ship". I just don't want to be left wondering if l could have done it better. So starting from square one, (except for the controllers), what would you recommend? I truly highly value your opinion(s)...and Thank you, once again.
less amps is better for the batteries (and easier to achieve..)
so I think I'd go for the 72V.
'sid
so I think I'd go for the 72V.
'sid
Bgt2u
Member
Okay, l will go with that.
As always, thank you.
P.S. while you were responding to me, l was editing my reply with some more little details, but the answer you just gave me still applies, and is what l will go with.
As always, thank you.P.S. while you were responding to me, l was editing my reply with some more little details, but the answer you just gave me still applies, and is what l will go with.