PowerFlex 753 Question

I have a 1769-L33ER communicating with a PowerFlex 753 Via Ethernet/IP. I have read many of the post on the site about the PF700 series and thanks to everyone things went very smooth and the drive is working great.

In my logic I am setting the START bit until the RUNNING bit is set. (as Ken has instructed on many posts ). I am also setting the FORWARD bit when I start the drive. I also send the reference speed via Ethernet/IP.

My question is: Do I need to set the FORWARD bit? This is a Centrifugal Pump application and it will always run forward. I was reading in the help menu of the drive that as long as I send a positive reference that the drive will always move the motor in the forward direction. So am I setting a redundant bit?

Just looking for a little more insight on how this all works.

Thanks for the help!!

Just a follow up. I removed the section of the code that used a forward command and the drive still started and ran the correct way. So I am guessing if you use a + speed reference the drive will move the motor forward. If you use a - speed reference the drive will move the motor backwards.

The forward and reverse bits are mode select bits. They are very similar to the forward and reverse buttons on a HIM. Just like you don't need to hold the forward or reverse button on a HIM to maintain direction you don't need to maintain the bits to maintain the selected direction. However, if the drive direction ever did get changed to reverse, your positive speed would make it run in reverse.

I haven't tried this but I THINK if you set the drive to accept a bipolar speed reference and you set the reverse bit the drive will run "reverse" with a positive speed reference and "forward" with a negative speed reference.

Keith