TReX Jr problem

Support Motor controllers/drivers and motors
1

Hi,
I have a problem with my TReX Jr. I have two motors, which I want to connect to TrEX controller. My motors: https://www.pololu.com/product/1573 . I configured channels etc and without any load LED indicators work correctly but when I have even one motor there is a problem with start up. I checked current received by one motor and it’s about 1,3A (max) to 0,3A (Free run) so it’s within limits. My power supply is a packet of 5 NiMH baterries - for one 2500mAh, 1.2V. So voltage for packet is ~6V and current efficiency ~2.5A. Problem is particularly similar to this video: https://www.youtube.com/watch?v=SNvlNAocLRc

Where is a problem? What is wrong ?

Thank you in advance.

2

Hello.

It sounds like you might be having a power issue. Is your battery pack freshly charged? Can you measure the voltage and let me know what it is?

Even though the gearmotors current draw might settle at around 1.3A, on startup the inrush current could be more like 6A (the stall current), and that could be causing your battery voltage to drop. If you try to accelerate the motor gradually, do things work normally? Do you have access to an oscilloscope that you could use to see what the battery voltage is doing as the motor starts running? Can you provide a video showing how your specific setup is working?

Grant