Hello. My sabretooth has detected a faulty motor I think. I have narrowed down to one of the 2 motors on my machine which I achieved by disconnecting it and running just on the remaining motor which perform satisfactorily, no red light. I am perplexed however that the "faulty " motor does not disclose any apparent faults other than causing jerky performance of the whole rig ,flashing red light, consistent red light and then controller cutoff. on reswitching to ON the same cycle repeats when jiggling the rc joystick . There’s no motor overheating, no jamming, no smoke. It looks fine. Both motors are brushed 44 amp 24volt geared 1kw each. I have checked for loose connection s and according to my meter not grounded. It’s a bit of a faff removing it but of course I will but I wondered if there’s a soul out there who might shed light before I do that. The 2 x60 is OK. I know because I have 2 and I changed the 2x60 as a first step to a known goodie. Worried that my lithium battery might be dodgey i tried a 24volt lead acid. Same result. It’s definitely one of the motor that’s causing the warning light but why?. It goes apparently without fault. Or can the sabretooth detect a minor short somewhere un the motor?
I would be most grateful for advice.
Thank you
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Hi @dede ,
Here are some points that you could check:
- check for shorts along the battery and motor lines. Even stray copper wire strands can cause this type of behavior which is exacerbated with higher torque.
- make sure that you reverse the power-up procedure. If you have the Saber DIPs set for auto-cal mode. So the transmitter should be powered-up first, before the Saber receives battery power. This ensures proper signal calibration.
- Also, there can be issue of the inhibition of regenerative current into the battery. What is the capacity of the batteries (amp hours, Ah)? What is the current rating of the battery disconnect switch? Do you have any other components on the battery lead besides the regulator for the receiver?
- Have the brakes been removed from the motors?
Thank you ever so much for your prompt reply, igor. I will go through these checks tomorrow and get back to you.
Regards David Ede
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You are welcome.
You can also write to manufacturer directly on [email protected]
They would know immediately what is the problem with your setup.
Hi, @dede ,
Here are some further troubleshooting methods you can try before disassembling it:
• Measure the motor winding resistance: Use the ohm of a multimeter to measure the resistance value of the winding of the faulty motor. Set the multimeter to an appropriate range and measure the resistance between each pin of the motor winding respectively. Under normal circumstances, the resistance value should conform to the rated parameters of the motor. If the measured value is significantly smaller, there may be a short circuit between windings; if the resistance value is infinite, there may be an open circuit fault.
• Check the motor current: If conditions permit, an ammeter can be used to measure the current when the motor is running. Connect the ammeter in series in the power supply circuit of the motor, start the motor, and observe whether the current is within the rated range. If the current is too high, and the reasons of excessive load and mechanical jamming are ruled out, it may be that the motor has problems such as a slight inter-turn short circuit in the winding.
• Listen to the motor running sound: When the motor is running, listen carefully for abnormal noises, such as harsh sounds, friction sounds, or abnormal buzzing sounds. These sounds may indicate internal faults in the motor, such as bearing damage or motor winding short circuits.
• Check the rotation of the motor shaft: When the power is off, gently rotate the motor shaft by hand to feel whether the rotation is smooth. If it is difficult to rotate or there is an obvious sense of jamming, the motor bearing may be damaged or foreign objects may enter the motor; if it rotates too easily without any resistance, there may also be problems inside the motor, such as abnormal magnetic fields caused by winding short circuits.
Even though you’ve already checked for loose connections, sometimes a bad connection can cause intermittent behavior. A loose connection or poor contact might cause voltage drops or current fluctuations that affect the controller’s performance.