Hi All,
I have been suffering for months now in designing a H bridge that controls a 36V DC motor with 3 Amps stall current and 1 Amp running current. The Transistors used to blow (TIP122 & TIP127) until I added a flywheel diode ( although there is once included in the transistor, however, my main problem now is that the controller (PIC16F84A) re-triggers and changes the motor direction when the power is cut out from an external limit switch. I have two limit switches witch paralleled diodes to stop the motor motion at the end of the stroke. I have added RCD snubber on the H bridge circuit at the +36 V and ground nodes but still I think the motor arcs and retriggers the controller. This phenomena only occurs at limit switch opening cutting the current from the motor. I am using a satalite dish linear actuator motor and using its cam and built in limit switched without amendment.
Anyone's help is mostly appreciated
I have been suffering for months now in designing a H bridge that controls a 36V DC motor with 3 Amps stall current and 1 Amp running current. The Transistors used to blow (TIP122 & TIP127) until I added a flywheel diode ( although there is once included in the transistor, however, my main problem now is that the controller (PIC16F84A) re-triggers and changes the motor direction when the power is cut out from an external limit switch. I have two limit switches witch paralleled diodes to stop the motor motion at the end of the stroke. I have added RCD snubber on the H bridge circuit at the +36 V and ground nodes but still I think the motor arcs and retriggers the controller. This phenomena only occurs at limit switch opening cutting the current from the motor. I am using a satalite dish linear actuator motor and using its cam and built in limit switched without amendment.
Anyone's help is mostly appreciated