How to reset nudrive inhibit LED?

[mitew]

I have a nuDrive power amplifier and right now, the INH status LED is on. 

Manual says, "This is the inhibit status LED (labeled INH). If a motor does not move when commanded and this LED is on, check that the nuDrive is enabled via the ENABLE switch, host interlock and external inhibit inputs, and not in an E-Stop condition."

I have done all the the above but the LED is still on. Is there any way to reset it. 

Thanks for your help.

best

[Greg-H]

Hi,

Do you have any signals connected to the external inhibit inputs or the E-Stop input?  It may be that the signals are set to be active low and with not signal they are disabling the drive.

Could you also provide the model number of the drive?

Regards,

Greg H.

[mitew]

Model Number 4CX-001.

The E-stop is not being used and the external inhibits are all disabled. Furthermore, the Inhibit is ON at power up.

Thanks,

[Greg-H]

Hi,

There is not a way to reset the inhibit LED.  The two things that could becausing this light are up the E-Stop or a bad connection from the computer.  The drive has a circuit which detects +5V from the host computer, if this voltage is not detected then the inhibit will be activated.  Also, have you tried connecting a signal to the E-Stop terminal?

Regards,

Greg H. 

[mitew]

I have not connected anything from to the E-Stop. Would the Inhinit LED be on if there is no cable connecetd to the nuDrive or when it is first powered up? Right now, it is on all the time. Also, I can I send an external +5V signal to that pin to see it would disable it?

[Greg-H]

Hi,

You will need to send a signal to the E-Stop pin or make sure it is set to active high, for troubleshooting purposes I suggest sending a signal.  The +5V is over the connection from the computer, so if you just hook it up to the computer it should see the +5V and you don't need to send an external one.

Regards,

Greg H.

[mitew]

I would like to run a 24V DC sevro motor using the nuDrive. However. when I connected the motor to the output from the nuDrive, the motor became hot. I measured the voltage out from the nuDriveto be +/-55.65V. How can I reduce the volatage to the appropriate level, below 24vDC in order to drive my motor.

[Joseph-S]

Hi mitew,

The only way to limit the peak voltage output from the nuDrive would be to use some external circuit. There is a way to limit the current that is supplied to the motor, but this would involve opening the drive and changing some of the resistors. The problem with this is that the peak voltage will not change, but the PWM frequency will be adjusted to lower the current consumption, meaning that the RMS voltage will be lower. The process is described in the manual here on page 19: http://www.ni.com/pdf/manuals/321942b.pdf.