Multiple 1771-ASB Adapter Faults

[scantime]

I have setup a ControlLogix rack with a remote PLC-5 rack. This is done via a ControlLogix 1756-DH+/RIO card connected to the PLC-5 rack via Blue-Hose, this Blue-Hose is landed on the 1771-ASB remote I/O adapter. This is a test setup that was working a couple of weeks ago. After installing some third-party RIO fiber-optic modules into the PLC-5 racks, the remote rack is no longer working. Additionally, a used and a brand-new 1771-ASB module were tested in the PLC-5 rack and appeared DOA (Angry, solid red "Adapter Fault" light). My question is: Could there be some other issue that is destroying the 1771-ASB modules? A bad PLC-5 rack? a bad power supply? I measured 5.10VDC on the backplane, so I'm not sure what else it could be. I'm getting another 1771-ASB module, but am afraid to insert it into this rack.

 

[OkiePC]

I would back up and punt the fiber optic modules first of all. Go back over the power requirements of all. Did you test your ASB modules in a known good rack? Is the blue hose properly terminated?

 

[JohnCalderwood]

Aye, he is right - punt the 3rd party stuff..!

But seriously...go back to where you were with the "working" configuration. Get that working, then start to connect individual items to see what and when it fails.
Even try the replacement 1771-ASB with nothing else in the rack to pull it down, just to eliminate where the fault lies.

 

[scantime]

I would back up and punt the fiber optic modules first of all. Go back over the power requirements of all. Did you test your ASB modules in a known good rack? Is the blue hose properly terminated?

OkiePC, thank you for the reply, I've no doubt been helped by some of your posts in the past and am honored that you responded to mine! As for the fiber-optic modules, I have left those out and tried the setup with solely a 1771-ASB module, 1771-P4S power supply and an otherwise empty 1771-A4B 16 slot PLC-5 chassis. A brand new ASB module appeared DOA, as did a used one, even after trying several different Blue-hose configurations. Unfortunately I don't have another chassis or power supply but I'm worried that either the power supply or chassis is somehow destroying modules, or I'm having really bad luck with ASB modules. This setup was working at one time, but there may have been an insertion under power of one of the fiber modules, which happened before trying the brand-new ASB module. Could this destroy a rack or PLC-5 power supply to the point where it would ruin any ASB module?