I have a TouchDRO for Shahe scales purchased from Yuriy in late 2020 on which the tacho function did not work at all. After consulting with Yuriy, the issue was a result of a change to the processor chip that prevented the tacho function from working. Yuriy supplied new firmware (v2.4), and after flashing the board, the tacho function now works (mostly).
The RPMs read fine when the motor is running, and the speed is changed, however when the motor is turned off, or ramped down to a stop the tacho does not read zero when the motor stops. Eg if the motor is running at 1000RPM, and I alter the speed, the tacho readout responds up and down as expected and reads the correct RPM. When I turn the motor off, the tacho reading stays "at the last reading" even once the motor is stationary. The displayed value depends upon how quickly the motor decelerates: as I run it from a VFD, the motor is braked and therefore comes to a stop fairly quickly.
Obviously, the tacho is still "reading the sensor" even when the motor is not rotating, and therefore should update the display with the "current motor speed" which is zero RPM. I have not been able to determine whether there is a threshold speed below which this occurs, and above which it reads normally.
I have another Touch DRO unit and the tacho goes to zero as the motor slows to a stop, and when stopped, it reads zero as you would expect.
Is there a fix for this?
The RPMs read fine when the motor is running, and the speed is changed, however when the motor is turned off, or ramped down to a stop the tacho does not read zero when the motor stops. Eg if the motor is running at 1000RPM, and I alter the speed, the tacho readout responds up and down as expected and reads the correct RPM. When I turn the motor off, the tacho reading stays "at the last reading" even once the motor is stationary. The displayed value depends upon how quickly the motor decelerates: as I run it from a VFD, the motor is braked and therefore comes to a stop fairly quickly.
Obviously, the tacho is still "reading the sensor" even when the motor is not rotating, and therefore should update the display with the "current motor speed" which is zero RPM. I have not been able to determine whether there is a threshold speed below which this occurs, and above which it reads normally.
I have another Touch DRO unit and the tacho goes to zero as the motor slows to a stop, and when stopped, it reads zero as you would expect.
Is there a fix for this?
