1784 pktx card malfunctioning

[rejoe.koshy]

hi,
I have a scada system in which 6 PLCs are connected via DH+ cable to a pc with a AB 1784 pktx card installed in it. I have configured rs linx but cannot find the online PLCs connected to it. The card is blinking green . What could be the problem??
need help urgently!!

 

[Ken Roach]

Was the card working previously, or are you attempting to set this 1784-PKTX up for the first time with this computer ?

If this card was working in the past and now the DH+ LED is blinking green and the PLC's don't show up in the network browse, then it is very likely that the DH+ wire is broken at some point in the daisy-chain.

The only way to figure out where is to use an oscilloscope to look for DH+ signals, or decommission the network and "ring it out" using a continuity or cabling tester.

 

[rejoe.koshy]

yes the card was workng fine in the past , but an attempt to download a program in to one of the plcs has triggered this problem..is there any possibility of a baud rate mismatch??

 

[rejoe.koshy]

i have checked the DH+ cable for breaks but could not find any.To reconfirm my conclusion i subjected the cable to continuity test & the results were in affirmation .
what could be the issue ?? need help guys !!

 

[OkiePC]

yes the card was workng fine in the past , but an attempt to download a program in to one of the plcs has triggered this problem..is there any possibility of a baud rate mismatch??

Is it possible you downloaded a program and created a duplicate node number?

 

[rejoe.koshy]

how do you assign a node to a processor??

 

[Mickey]

how do you assign a node to a processor??

What processor(s) are you using? And which channel are you using on those processors?

 

[rejoe.koshy]

out of six connected processors,4 are PLC-5/40 E & two are SLC-5/04.Channel 1 is used for SLC- 5/04 processors & channel 1A for PLC-5/40 E processors

 

[Mickey]

out of six connected processors,4 are PLC-5/40 E & two are SLC-5/04.Channel 1 is used for SLC- 5/04 processors & channel 1A for PLC-5/40 E processors

The node addresses for your SLC5/04's are software configurable, go to channel configuration and change it there.
The node addresses for your PLC5/40 channel 1A is set by dip switches on the controller.