This is a "process issue". There is no single thing that explains what your problem is.
Your problem is, as you have confessed, you are a complete novice. As such, the process you followed , every step of the way was based on your limited experience.
Let's look at the facts:
Here's the specs on the motor: (THAT MEANS ONE MOTOR, NOT TWO)
Specifications
- Bolt Pattern: 2 #10-32 Holes on a 2 in. diameter bolt circle
- Duty Cycle: Intermittent
- Free Current: 2.7 AMPs
- Free Speed: 5310 RPM
- Maximum Power: 337 Watts
Do the math: 2 x 337 = 674 W
Here's the motor driver:
7A/160W Dual H-Bridge Motor Controller
What's wrong with this picture ?
Does this mean the motors ate able to carry the
load ?
"Now, I made this exact connection with a regular L298N, dual H-bridge motor driver (rated for 2A), and the motors actually spun how I wanted them to, but the main issue being the H-bridge would get extremely hot after 10s or so."
Just how long did you run the motors before
stopping ?
Ok, so we know why you made the wrong choices so there's no point in dwelling on that. The question is :
If the PROCESS YOU used was WRONG, WHAT is the RIGHT PROCESS ?
Well it starts with listing , or generating , your Design Criteria. This is always done from the load up. The load is evaluated to select the correct motor, that being one that can carry that load. The motor spec is then used to select the motor driver. The two , take as a whole , are evaluated to select the power source, which , if batteries, means selecting the:
TYPE
NUMBER OF BATTERIES
The mAh rating
DISCHARGE RATING (25C,50C etc) if LIPO, or some other similar spec.
Hindsight is always 20/20 but if you look at the above, it would appear, the problem arose because you did not
consult us at the beginning to help you select the motor driver. Why didn't you consult us ? Well, if you are young , it was probably a case of you seeing it as a challenge and of course we don't know why you thought you were capable of selecting the motor driver when you readily admit to being a novice. On the face of it this doesn't seem a wise choice. I can tell you from experience I was the same way when I first became an electronics technician (about 40 years ago) There were situations that came up where I was faced with a decision to try to do it myself, or to admit to someone I didn't know what to do and as you can imagine I made some bad choices and after several bad choices, I was told in no uncertain terms that if I wanted to keep my job, under NO circumstances was I to take any action unless I was 90% certain (and could explain WHY) that those choices were correct. It is a common expression repeated to people every day in the electronics (and I suppose many other industries) "If you don't know what you are doing , DON'T DO ANYTHING !"
That being said, let's address some of your questions:
And do you have any suggestions to mitigate this issue?
As far as mitigating the issue, yeah, don't order stuff if you don't know how to choose what to order.
Is that harsh ? If you think about it , that's pretty irrelevant. You are not asking us to tell you what you did wrong without telling you what you did wrong. You came here because you are seeking the truth. Can you handle the
truth ? (I don't know . That's for you to decide) The point is , the DROK billed as a 7A driver , and if you take the
motor rating of 337W maximum power and divide it by the battery voltage you get what ? (28.3A/per motor).
Choosing a 7A driver for a motor that could pull 28A is asking for trouble, as you found out. I would guess the
cratered power device made a loud bang when it blew, and propelled small plastic shrapnel outward.
When working with motor drivers not enclosed in boxes, it's best to wear safety glasses to avoid eye damage if
a mosfet fails catastrophically.
Is it possible my battery is providing too high of an amperage, that is frying the DROK motor driver (but for some reason, not the smaller motor driver)?
Yes and NO. The short answer is that if you had used an inadequate battery, it would not have had an internal resistance low enough to blow the driver power devices. That being said, you used the correct battery because it
was able to provide enough power. The problem was not the motors or the battery but the weak link (as already
mentioned by several others I think) being the motor driver. You don't have to be math genius to see that the
math doesn't add up when you compare the motor power rating to the driver power rating. That driver would
have worked just fine with a much smaller motor. My personal feeling is that if you consider worst case and add
a 25% safety margin to the 337W/per motor, that gives you 421W per motor x two motors = 842W. If you then
add a little extra safety margin that puts you at 1000W for both motors or 500W/per motor. Obviously you have
a limited budget so you don't have the luxury of choosing anything so l would recommend something like the
following motor driver , reason being it is billed as a 43A driver and if you power source is 12V, the most common
dc motor voltage, that gives you 43A x 12V =516W per motor which is right in the ball park, with a little margin
to spare. Now, about your battery; you can do the math: 8A x 12V = 96W total (or 48W per motor) which fits right in with the 43A per motor driver.
Why didn't you fit a fuse to such a potential high current supply as your battery?
What sort/spec is the battery?
Some kind of fuse is not a bad idea, under the circumstances.
Did you ever measure the battery current ?
