i have ibt-2 device bts7960b on-board.
it has been wired single motor (dc hobby type) provide forward pwm speed control , variable fast braking. control software , wiring works designed. power motors 12v , various motors draw less 1amp when running @ full speed. quick measurements indicate can draw 2amps when starting (under little load these powering slot cars , car lifted track has accelerate motor , wheels etc).
the lower power motors run fine higher rated motors draw current behave badly under following conditions...
the trigger on hand controller (causing pwm input speed ibt-2) varied between low duty cycle , high 1 , motor speeds up/slows down. if trigger action done @ particular rate, 2/3 times second, possible hear motor not being driven when should be. picks after moment , 'stalls' again. have larger motor heavier flywheel on (still rated 6v - 15v) , possible hear doing same thing one.
i can see current drops 0 when motor should being powered , have checked 'scope , can see pwm output ibt-2 still should be... doesn't shoot 0 randomly.
i built system using same pwm output driven arduino plugged tb6612fng (a lighter duty controller within specs steady running of these small hobby motors). uses same pin logic ibt-2 , once again works lower power motors drops out more powerful ones in more obvious way. motor stop , after second or start again @ appropriate speed pwm input.
i don't suspect arduino sketch , output of pwm despite 2 different speed controllers behaving in same way. suspect motor controller board/chip kicking in sort self defence mechanism. ibt-2 rated @ 43amps , don't see current of these little motors getting big in stall. don't think chip getting instantaneously hot. don't know high voltage spikes coming don't know sure.
does have suggestions possible cause and/or in chasing 1 down. stands system not usable on track (which problem first noticed 1 of better racers @ club) causes car hesitate little , affects drive-ability.
thank alan
it has been wired single motor (dc hobby type) provide forward pwm speed control , variable fast braking. control software , wiring works designed. power motors 12v , various motors draw less 1amp when running @ full speed. quick measurements indicate can draw 2amps when starting (under little load these powering slot cars , car lifted track has accelerate motor , wheels etc).
the lower power motors run fine higher rated motors draw current behave badly under following conditions...
the trigger on hand controller (causing pwm input speed ibt-2) varied between low duty cycle , high 1 , motor speeds up/slows down. if trigger action done @ particular rate, 2/3 times second, possible hear motor not being driven when should be. picks after moment , 'stalls' again. have larger motor heavier flywheel on (still rated 6v - 15v) , possible hear doing same thing one.
i can see current drops 0 when motor should being powered , have checked 'scope , can see pwm output ibt-2 still should be... doesn't shoot 0 randomly.
i built system using same pwm output driven arduino plugged tb6612fng (a lighter duty controller within specs steady running of these small hobby motors). uses same pin logic ibt-2 , once again works lower power motors drops out more powerful ones in more obvious way. motor stop , after second or start again @ appropriate speed pwm input.
i don't suspect arduino sketch , output of pwm despite 2 different speed controllers behaving in same way. suspect motor controller board/chip kicking in sort self defence mechanism. ibt-2 rated @ 43amps , don't see current of these little motors getting big in stall. don't think chip getting instantaneously hot. don't know high voltage spikes coming don't know sure.
does have suggestions possible cause and/or in chasing 1 down. stands system not usable on track (which problem first noticed 1 of better racers @ club) causes car hesitate little , affects drive-ability.
thank alan
as can seen there wasn't in way of response one. fixed though didn't find out broken!
i didn't think code faulty or wiring looked ibt-2 itself.
this board wraps 2 bts7960b motor drivers in h bridge configuration , presents pins on board can control in way think should able to. has on board octal converter, selection of resistors , capacitors , 1 whopping great capacitor. 1 must assume these things important , useful stuff isn't documented (at least couldn't find above , beyond bts7960b datasheet).
i use ibt-2 in half bridge mode there no requirement reversing motor. decided wire single bts7960b on breadboard in accordance datasheet , hey presto worked properly.
so can't wrong have done has fixed , new (and smaller solution) installed in latest hand controller.
i may, if time permits, take out big capacitor , see happens that's day...
i didn't think code faulty or wiring looked ibt-2 itself.
this board wraps 2 bts7960b motor drivers in h bridge configuration , presents pins on board can control in way think should able to. has on board octal converter, selection of resistors , capacitors , 1 whopping great capacitor. 1 must assume these things important , useful stuff isn't documented (at least couldn't find above , beyond bts7960b datasheet).
i use ibt-2 in half bridge mode there no requirement reversing motor. decided wire single bts7960b on breadboard in accordance datasheet , hey presto worked properly.
so can't wrong have done has fixed , new (and smaller solution) installed in latest hand controller.
i may, if time permits, take out big capacitor , see happens that's day...
Arduino Forum > Using Arduino > Motors, Mechanics, and Power (Moderator: fabioc84) > Hesitating IBT-2 device with bts7960b (FIXED'ish)
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