PowerFlex 70 & 700 With Slave drives via 20-Comm-E

[curlyandshemp]

We have a customer that has asked to quote on a Contrologix project. Most of the field I/O is via Ethernet I/P with several PowerFlex drives using the 20-Comm-E ethernet I/P adapter. This customer has also been told by their local hardware supplier, that a PowerFlex can also have up to 4 drives connected in series to that only 1 20-Comm-E is required for every 5 drives.

I am searching high and low and cannot find any documention on this, or how I would communicate to these four other drives through the 1 20-Comm-E.

Can this actually be done?

 

[Ken Roach]

They're thinking of the "Multi-Drive Mode" with the PowerFlex 40 and the 22-COMM-E. A single 22-COMM-E can be put into Multi-Drive Mode and can command up to five other drives on a 2-wire RS485 "DSI" protocol network that are daisy-chained downstream of the 22-COMM-E.

Multi-Drive Mode precludes parameter messaging to any of the drives, I think. And it's slow, by comparison; allow about 35 millisecond per drive for the data exchange in each cyclic I/O interval.

The 20-COMM-E is capable of commanding a PowerFlex 70/700 drive in about 5 milliseconds and provides web, e-mail, parameter access, diagnostics, and full DPI network bridging. It's the higher-performance network interface for a higher-performance drive family.

 

[curlyandshemp]

They're thinking of the "Multi-Drive Mode" with the PowerFlex 40 and the 22-COMM-E. A single 22-COMM-E can be put into Multi-Drive Mode and can command up to five other drives on a 2-wire RS485 "DSI" protocol network that are daisy-chained downstream of the 22-COMM-E.

Multi-Drive Mode precludes parameter messaging to any of the drives, I think. And it's slow, by comparison; allow about 35 millisecond per drive for the data exchange in each cyclic I/O interval.

The 20-COMM-E is capable of commanding a PowerFlex 70/700 drive in about 5 milliseconds and provides web, e-mail, parameter access, diagnostics, and full DPI network bridging. It's the higher-performance network interface for a higher-performance drive family.

Thanks Ken,

I found the info I was looking for in the 22-Comm-E manual. This is going to be a pain. Each of the up to 4 additional drives can only be setup in Single Node mode using a HIM , then switched to Multi-Drive mode where the HIM will no be able to be used.

I have 4 sets of 4 additional drives to set up.

 

[Ken Roach]

Hold on, let's make sure we understand the whole issue.

PowerFlex 70/700/7000 drives use the 20-COMM-E
PowerFlex 4/40/400 drives use the 22-COMM-E.

If you are planning to use PowerFlex 70 and 700 drives, you can only use the 20-COMM-E, which does not support the "Multi-Drive Mode".

 

[curlyandshemp]

Hold on, let's make sure we understand the whole issue.

PowerFlex 70/700/7000 drives use the 20-COMM-E
PowerFlex 4/40/400 drives use the 22-COMM-E.

If you are planning to use PowerFlex 70 and 700 drives, you can only use the 20-COMM-E, which does not support the "Multi-Drive Mode".

I will make sure the customer understands that PowerFlex 40s are to be used, I assumed they were using PowerFlex 70/700.

I am now aware the 22-Comm-E is the only one that supports Multi-drive mode.

Thanks again

 

[Ken Roach]

Just be sure that you and your customer understand the performance differences between 40's and 70's.

Changing drive types to avoid buying communication modules seems like an inverted decision model to me.

 

[curlyandshemp]

Just be sure that you and your customer understand the performance differences between 40's and 70's.

Changing drive types to avoid buying communication modules seems like an inverted decision model to me.

This customer has an inhouse mechanical engineering who thinks he knows it all. Originally this guy designed this system to have
one Compactlogix L32e with 4 fully loaded analog Flex I/O drops, 200 Festo Ethernet valves, 4 PowerFlex Ethernet VFDs each with 4 multi-drives, 3 PV1500+ and one RSView SE station all on the same ethernet connection to the compactlogix. He claimed Rockwell configured this for him.

First thing I did was to tell him get a Contrologix L6X with at 2 1756-EN2T, one for I/O and other for HMI SCADA. As far as VFDs go , they are only for agitators, so the lower performance difference is not an issue.