Hiya guys, banging my head against brick wall now as im un-decided to go 12 or 24 volt in terms of motor for my tug!
heres the specs of tug:
Length 71" (about 1.8meter)
Beam (18") (about 45cm)
Total weight with ballast etc 50-60kg? (this is a guess at the mo as im awaiting for my hull, so until then i wont know 100% exact weight)
Prop 15cm Diamater 4 blade with a 7" pitch (OR a 12cm 4 blade with a 6" pitch, not too sure at mo which would be best?)
Now ive been googling for days which is best setup, am i right in thinking that with a 24 volt motor using a 24 volt power source will draw LESS amps than a 12volt battery/motor combo? ..because alot of articles i've read seem to indicate that 24volt is the best option, the downside is the weight, but for my build that is actually a bonus as i need the weight for the ballast! But even if i did use a 12volt motor i would still use 2x 12 volt battery and run them parallel instead for the extra capacity. I also read that 12volt motors if worked hard can over heat! ..with my hull being the size it is & the weight its going to be i feel that a 12 volt motor may struggle compared to a 24 volt motor?
Ive decided (whichever voltage i use) to go with the Action Electronics ESC, they offer a high voltage ESC (12-30 volt) or numerous others that are for 12 volt.
Motor wise, ive came across two for 24 volt which have an max RPM of 4000, one states it is 150 watt & the other states it has 12 poles , but as yet i've not looked for a 12 volt one suitable as i have always leaned towards running a 24 volt motor.
Anyway like i say im unsure now which route to take, im going to be placing the order this week for most of the electronics, but before i do i want to try make sure i get the correct items!
here's just one article i read on this matter, it was about someone asking if they could run there 12v motor on a 24v supply, but the guy responded with the below which is what im kind of asking:
"On their respective power supplies both motors should perform identically but the 12V motor would draw twice as much current from its 12V supply compared to the 24V motor on a 24V supply.
In other words power supplied to both motors should be quite similar for a given mechanical load. Mechanical load power is defined as 2πnT2πnT where n is speed in revs per second and T is torque is newton-metres. And if the 12V motor took 4 Amps to supply a certain mechanical power output then the 24V motor would take 2A to perform identically.
DC motors of the simple type (trying not to generalize here) will rotate at full speed on no-load and this speed is mainly determined by the applied voltage. Putting 24V on a 12V motor may wreck it. Conversely, on heavy loads, the speed normally reduces fairly linearly with torque but on a 24V supply there may be enough potential for the motor to fry due to it being able to supply more torque and speed. Don't do it is my advice."
Is this true? I read it on an electronics forum... im guessing the chap knows what hes on about! lol
As always, any advice would be greatly appreciated!
Thanks guys/gals :)
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Topic: 12 volt or 24 volt!? (Read 1275 times)