DIY Motorcontroller

HavoKane

anyone know of a good one i can build myself, relativly cheap that has FWD and RVS? i have (2x) 12v(max) 20A(max) car window motors i want to use on my robot. i want to build it myself simply because of the fact that its cheaper. i looked at the HB-25, but i cant justify the cost for a hobby. i searched google a little, but didnt find anything too great.

Paul Baker

Research H-Bridge, then use transistors capable of carrying the current you need.

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1+1=10

Cheeto

I looked into the L293, is it possible to hook to the two direction pins to i/o on the stamp and then hook the enable pin to a Servo Controller and use a serout to control the speed of the motors ?

This pdf is helpful downloads.solarbotics.com/PDF/kit10.pdf

This looks like exactly what i want to do
www.bobblick.com/techref/projects/sv2pwm/sv2pwm.html

Post Edited (Cheeto) : 6/3/2006 12:50:52 AM GMT

LoopyByteloose

20 amps is really heavy wire [noparse][[/noparse]18 12 guage copper].· The HB-25 will handle it all with ease.· But from what I understand, the limit of printed circuit board is about 5 amps under ordinary design.

S0, the real question is whether you want a durible designed product or something that may be relatively short-lived.· Just having a schematic on paper is not enough in this case.· All the power output side components need to be rated at 20 amps or greater AND it certainly wouldn't hurt to have some fuses and thermal shut down.· You may also have transient peaks far beyond the 20 amps if there is a jam up.

The L293 won't work, just smoke.· Have you considered trying some double pole, double throw relays?· They are a bit noisy and slow, but for DIY it is the easiest.


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"You have to have a dream so you can get up in the morning." - Billy Wilder 1906-?


·······································································Tropical regards,····· G. Herzog [noparse][[/noparse]·黃鶴 ]·in Taiwan

Post Edited (Kramer) : 6/11/2006 10:36:19 AM GMT

Robert Kubichek

18 guage copper wire is only rated for 2.3 amps (power transmission) max amperage at a connection to pc board is 16 amps
You might be pushing the limits of the wire you are using, not to mention the heat problems associated with such a light wire/heavy load.
I would use at least a 14 guage finely stranded copper wire....

Bob N9LVU