Running a Danfoss VLT micro drive using Allen Bradly Mirco850

ASF said:

Not all drives have safe torque off, if yours doesn't you can disregard.

The drive can be configured to look at Modbus, Digital Inputs, or Both. Make sure it's not set to both.

As per my previous post, Reference 1 Source is the parameter you need to look at for sending a speed reference over modbus. Of course you also need to make sure that Reference 1 is selected, but generally it will be selected by default.

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Ah thank you. I have set the drive to listen to both Digital Inputs and Modbus. So it might be that. Can't make changes at the moment but will certainly look at that when the load shedding ends.

For content: South Africa has about 8 hours a day at almost random intervals where our power is cut but the employees of the national power provider because they want additional wages increases... makes working to a schedule very difficult.

It's likely that's the case. If you're listening to both digital inputs and modbus, you're probably getting a start signal from modbus and a stop signal from the digital inputs (because the stop signal will be a "0=stop, 1=no stop" arrangement, and your stop input is not connected), and a stop input will override a start input. I don't know this for sure as I've not used Danfoss drives extensively, but on other drives I am more familiar with, that's exactly how it works.