I am looking for some consultation about controlling a24VDC worm gear moto. I have blown 4 h bridge motor drivers thus far and while I have been trying to keep my project price tag low I may need to step up in quality but I want to make sure something else may be going wrong. I am a ME by trade but I remembered a smidgen about inductive loads and back EMF wreaking havoc on components. I have been using the following: driver 1 and driver 2 to control the motor but they keep failing and at random times. This makes me suspect not my wiring but something else and possibly not protecting the components. My most recent board was working, next thing you know the ERR LED light is on and the manual says “ERR LED Indicator – Error LED Indicator, it will illuminate when fault detected in on board MOSFET driver.”
I would think a motor driver board would know it would be dealing with inductive loads and protect against this but maybe I am wrong. Do I need to spend more money on someting like the following?
Help a poor ME sticking his toe in the water of electronics!
- What is the frequency of the pwm? Generally I’d put a varistor (MOV) across the motor terminals as close to the motor as possible. Something like a 20mm 30V device. – Kartman 1 hour ago
- @TheCodeNovice, Just now I skimmed the Pololu motor driver you are considering, to get a rough idea of your requirements: (1) Pololu G2 High-Power Motor Driver 24v13 (6.5V to 40V, cont 13 A without heat sink, no over-temperature, over current shut-off) pololu.com/product/2992. My first impression is that it is not newbie proof, because over temperature and over current can fry the driver! 🙂 – tlfong01 49 mins ago
- @Kartman my pwm frequency is 10kHz. Do you have a link of MOV so I know what I am looking for? – TheCodeNovice 46 mins ago
- @tlfong01, Would it over heat with out running the motor? I do not think that worm gear motor I am using will run close close to the rated 13A that is why I thought I could slide by without it. Do you know of a nice noob level h bridge brand I could use? – TheCodeNovice 44 mins ago
- Google MOV 20mm 30V – Kartman 42 mins ago
- @TheCodeNovice, well, I did fry many gear motors (do’t ask me how many, but I do have spare gear heads, just in case! :)). One of the many reasons are (1) physically overloading, (2) gear stuck or crashed, (3) start current which might be many times of operating current (so Pololu suggests ways to avoid bad things happening, by using big cap near PSU, or slow slow starters). – tlfong01 33 mins ago
- For motor newbies, I usually recommend the following Q&A: How to use motor drivers with H-bridge and PWM input, to control direction and speed of DC motors? – EESE, Asked 2020jul16, Viewed 1k times electronics.stackexchange.com/questions/510755/…. I usually newbies to start with plain, old, very power inefficient, stupid, L298N bipolar H-bridge, 4A driver, which has built in Schotty flyback diodes on board/module to protect back EMF. – tlfong01 22 mins ago
- You can start messing around with the very popular yellowish, cheapy TT130 gear toy motor with operating current around 350mA, and stall current less than L298N’s max 4A (So it is very difficult for newbies to fry the driver!). After you have gained some experience and confidence, you can bravely go up using mid level MOSFET H-bridges, and perhaps catch up me, the motor driver ninja, with my BTN7971B, max 43A, with current control, current sensing etc etc. You can search “BTS7970”, “BTN7971B” for my related answers. Ah, I missed my locking down morning tea. Good luck and see you later. – tlfong01 14 mins ago