1756-DHRIO to Powerflex 20-COMM-R

I'm currently trying to connect my controllogix system to a Powerflex 753 VFD. I installed the 20-COMM-R card in the VFD as a RIO adapter.

Whenever I set up the 1756-DHRIO module, under the channel devices the closest selection I have is Generic Remote I/O adapter, I set up the RIO address as 1, rack size (1/4) group 0, and the same info in the VFD, but I constantly get a red flashing light on the 1756-DHRIO channel, and the error is INVALID LINK ADDRESS.

It doesn't matter if I'm connected or not with the blue hose cable. I tried channel B, and reinstalling the module.

Any ideas of what may be wrong?

Thanks
Dave

Try swapping the blue and clear wires, of course.... you've always got a 50/50 chance on those.

Be sure you've got the mode (DH+ vs RIO) rotary selection switches set up on the 1756-DHRIO and have it set for the same baud rate in RSLogix 5000 and in the PowerFlex drive.

Try setting the 20-COMM-R for a 1/2 Rack size. While I haven't worked on these much lately, I recall that they essentially always need the first word for block transfer, so if you want to do Command and Reference inside the RIO image, the minimum size is 1/2 Rack.

Thanks, I've tried all of that except swapping the blue and clear. (I'll attemp that when I get back out there)

The modules are alwys set to DH+, so I know about the rotary switch. The baud rate I set in RS5000 and the comm card, that is matching at 57.6K

I tried the 1/2 rack option also. Still keep getting the red flashing light, even when I unplug the cable, I would think I would get a different error since it's not talking the the drive.

The INVALID LINK ADDRESS definition is, but doesn't help me much:


Verify that the ControlNet node number is not greater than the maximum node number configured for the network in RSNetWorx for ControlNet software.

Oh wow, tried swapping the blue and clear, and BINGO! came right up. Must be opposite than the 1336 VFD's that used to bein it's place.

Thanks for the tip, Ken!

OK, this comment is way off topic, and LMDAVE I'm not knocking what you're doing. Sometimes you have to do what it takes to get it done. But I had to laugh just a little. Connecting a ControlLogix and a PF753 with RIO is kinda like connecting two super computers with a telephone modem....

As usual, Ken comes through with the fix!

The Ballad of the Blue Hose

Once upon a time in 1978, the idea was that Blue on top (Pin 1) meant the port was RIO and Clear on top meant the port was DH+.

But then came everything else; the SLC-5/04 port, the 1747-SN, the 1336 Classic and 1336 Plus and 1305 and FLEX I/O and PanelView Classic and Standard and Enhanced and Block I/O.... there were no longer standard pin locations or orientations.

Even if you're extremely careful and conscientious... somebody's going to have swapped the colors inside a junction box for a long-gone Redipanel downstairs in a disused lavatory with a sign on the door saying "beware of the leopard".

So when I can't get a DH+ or RIO device going green-light, I always swap the wires.