G
greenwanderer108
- Jan 1, 1970
- 0
Hi, I'm an American living in Bangkok, Thailand. I'm new to this forum an
an absolute novice with basic electronics, I was hoping someone here ca
assist me with a few basic questions.
I'm planning to convert my bycycle electric in the near future (after som
electrical enlightenment of course). I've basically narrowed the motor dow
to a 24 VDC 250 watt motor. (Though 350 and 500 watt are also options)
Using Ohm's law (I think), I calculated that such a motor's current dra
would be aprox. 10.416 amps (250 watts / 24 volt = 10.416 amps), which
assume from reading other threads here, is what the motor would draw a
one hour under load. (Please don't hesitate to correct me--elaborate)
As for power supply, I've decided that I want to rig six 12 volt 1
amp/hour batteries in series-paralell for a total of 24 volts, 30 amp/hou
power supply. This I figure should give me roughly two hours of motor wor
between charges...
Assuming my calculations are correct, my next task is to figure out th
necesarry (speed) controller. I've browsed the many schematics/theorie
for DC motor controllers and am lost. I'm assuming a Pulse Width Modulato
circuit is what I'm looking for (rigged with a handle grip motorcycl
throttle set-up for precise control). So, then, I would like to know i
how to decide which particular circuit will suffice for the amp and vol
consumption required for my particular project.
Most every PWM circuit/schematics I've come across on the web are for lo
amp consuming loads. As I mentioned, the motor will be drawing atleast 1
amps. What is the theory and/or calculations for amp consumption in D
motor controllers?
Ideally, a universal controller that would work for 250, 350, and 500 wat
24 VDC motor with minimal power loss would be best. Ofcourse, I would lik
to know what determines/controls the current load/consumption in a contro
circuit. There is so much to decipher among---MOSFET, other capacitors
diodes, that I have still yet to learn their functions, purposes.
While we're at it, how does adding more amp/hours (placing more cells i
paralell) to the power supply (battery pack) affect the control circuit
In other words, how must the control circuit be modified to accomadate th
extra current without overloading/overheating the circuit, load, etc.?
Thanks in advance,
Steven
This message was sent using the sci.electronics.basics web interface o
www.Electronics-Related.com
an absolute novice with basic electronics, I was hoping someone here ca
assist me with a few basic questions.
I'm planning to convert my bycycle electric in the near future (after som
electrical enlightenment of course). I've basically narrowed the motor dow
to a 24 VDC 250 watt motor. (Though 350 and 500 watt are also options)
Using Ohm's law (I think), I calculated that such a motor's current dra
would be aprox. 10.416 amps (250 watts / 24 volt = 10.416 amps), which
assume from reading other threads here, is what the motor would draw a
one hour under load. (Please don't hesitate to correct me--elaborate)
As for power supply, I've decided that I want to rig six 12 volt 1
amp/hour batteries in series-paralell for a total of 24 volts, 30 amp/hou
power supply. This I figure should give me roughly two hours of motor wor
between charges...
Assuming my calculations are correct, my next task is to figure out th
necesarry (speed) controller. I've browsed the many schematics/theorie
for DC motor controllers and am lost. I'm assuming a Pulse Width Modulato
circuit is what I'm looking for (rigged with a handle grip motorcycl
throttle set-up for precise control). So, then, I would like to know i
how to decide which particular circuit will suffice for the amp and vol
consumption required for my particular project.
Most every PWM circuit/schematics I've come across on the web are for lo
amp consuming loads. As I mentioned, the motor will be drawing atleast 1
amps. What is the theory and/or calculations for amp consumption in D
motor controllers?
Ideally, a universal controller that would work for 250, 350, and 500 wat
24 VDC motor with minimal power loss would be best. Ofcourse, I would lik
to know what determines/controls the current load/consumption in a contro
circuit. There is so much to decipher among---MOSFET, other capacitors
diodes, that I have still yet to learn their functions, purposes.
While we're at it, how does adding more amp/hours (placing more cells i
paralell) to the power supply (battery pack) affect the control circuit
In other words, how must the control circuit be modified to accomadate th
extra current without overloading/overheating the circuit, load, etc.?
Thanks in advance,
Steven
This message was sent using the sci.electronics.basics web interface o
www.Electronics-Related.com