eloverphx wrote:Ok Tronic and all you other smart kids out here, HELP ME PLEASE!!! I can't figure this H-bridge problem out. I can run small motors fine. I run a small rc car motor with a 9v battery and everything works great. It goes both directions with no problem and there is no heat build up on the FET's. As soon as I try a wiper motor the FET's get hot immediately. I took voltage readings at the output when I tap the motor and it goes to zero like there was a short. The wiper motor work fine in both directions with the power supply only. As soon as I try to put the High current draw through the FET's they heat up and I get the wiper motor to to barely shake before the FET's are fried and turned to garbage. What am I missing? Why can't I get the wiper motors to work? The motors are sitting on a plastic table and I'm only working with one motor at a time. I'm ready to tear the whole H-bridge apart and try to build a new one, maybe the yobuddy ez board next, but I would much rather make this work and learn what the "f" is going on.. Thanks for your time.
jyrki.j.koivisto wrote:most mosfets don't like the gate voltage to be too high, maximun is in the order of 20volts. Motors act as a generator and if there is insufficient capasitance then the voltage will raise from the nominal 18volts and bad things can and will happen if the gate voltage rises (I assume there is no limiting circuitry on the gate, I haven't looked though)
|Tronic's DIY dual Mosfet H-bridge (DSMhb)||Forum: Motor actuators and drivers||Author: tronicgr||Replies: 366|
|2DOF Arduino controller with integrated H-Bridge||Forum: X-Simulator compatible hardware||Author: intructable||Replies: 20|
|HPMhb-150A (high power h-bridge)||Forum: Motor actuators and drivers||Author: R-eng||Replies: 59|
|Bau eines AVR 1.5 Motion Controllers von Thanos||Forum: X-Simulator compatible hardware||Author: TheXRacer||Replies: 1|
|Velleman k8055 + Thanos dual simple mosfet hbridge 1.2b||Forum: DIY motion simulator projects||Author: TheXRacer||Replies: 3|
Users browsing this forum: No registered users and 0 guests