T200 Beeping and Not Working

I am running two T200’s from an Arduino Due using PWM and they have been working great without any issues until today both stopped working and starting flashing the 1 2 3 lights. I followed the tutorial on this site and reflashed the firmware to the ESC. This stopped the flashing but created another issue. Now, when I power on the thrusters, the blue and red lights flash real quick along with usual beeping and then there is a short beep every four seconds and they won’t respond to PWM input. Does anyone have any insight into what might be causing this?

Also, one of the thrusters would turn on for a short while and then the blue light would go out and it responded to PWM inputs but then this suddenly stopped happening also. No clue whats going on and I’m on a short deadline for a University project so any help is greatly appreciated.

Does the ESC behavior match any documented in the troubleshooting section at the end of this document?
It sounds like they are not receiving a valid PWM signal. If you can, post your code.

Hi Reid,

This does sound like a problem with the PWM signal. The ESC will beep every 4 seconds if it isn’t receiving a signal. The blue light will stay lit until it receives a proper initialization signal (1500 µs) and then it will turn off.

Can you tell us more about how you have the thruster wired?



If I’m not mistaken the Arduino Due is a 3.3V processor.

I got the same problem intermittently when with a 3.3V PWM driver, which is right at the limit of what the ESC can detect. I switched my driver to active low mode and used pullup resistors to 5V, then it worked 100%.


Hello Rusty,

Should ESC continuously receive signal even when when I need to keep the same speed or it’s ok to send signal only when speed of thruster need to be changed.


Hi Alex,

The ESC needs to receive a constant signal or it will stop running the motor. That’s for safety, so that if the signal is lost for some reason, the motor will stop spinning.


Thanks for the fast replay. In spec, it stated that Max Update Rate is 400 Hz. So what the minimum Update rate, in other words, if the signal gets lost, how much time will pass when an ESC will stop a motor?


Hi @Alex1,

I’m not totally sure what the bare minimum is, but I would suggest not going below the standard update frequency of 50 Hz expected by most ESCs and servos.


Thank you.

Hello Blue Robotics,

Would you please give me your thoughts about my project?
I need to place ESC with attached heat sink into pvc pipe and seal it. I’m wondering if ESC will not be overheated of running on 50% load. What do you think?

Please see attached picture.



Hi @Alex1,

PVC has very poor thermal conductivity, if the ESC is sealed in place it may overheat in continuous use, even at 50%. I’ve never tried this myself, so I can’t say for sure. I can say that at 100% throttle continuous use, it would definitely overheat within minutes.