Hi guys,
I'm having problems with our Citect trends from our PLCs based on our DH+ network at our workplace.
I've recently been put in charge of administrating the local PLC network and Citect system.
I am mostly self taught, but do know a reasonable amount about both, but have been stumped with the problems we are having.
Firstly our networking layout is as follows:
-Ethernet network connecting all our PCs, phones, and Control/CompactLogix PLCs and panelviews (roughly 80 PLCs), which all seem to be working fine.
-Connect to the Ethernet is 2 DHRIO cards, each with 2 DH+ channels on them. 3 of the 4 channels have no problem, but one of them is having a lot of problems with a lot of data loss on the Citect trend pages.
-Connected to the DH+ network is 2 DH+ to DH485 adapters, which the DH485 network has about 8 nodes.
The problem DH+ network has 19 nodes, 15 Allen Bradley-5/04 PLCs, 2 Allen Bradley PV-700 HMIs, and the 2 DH+ to DH485 adapters.
The total network cable length would be about 400m, and longest run would be 50m.
Citect is monitoring about 250 tags from the PLCs on that DH+ network, about 1/3 of which have a 1 second sample time, and most of the others have a 5-10 second sample time.
While monitoring the tags on Citect runtime, there seems to be periods of data loss, 5-10 mins at a time, several times an hour. It seems random, and not happening more during day or night. This doesn't happen at all on any other networks DH+ or otherwise.
Also we are trending 8 tags from the DH485 network, which have not worked since the start.
We have gone over all the connections several times, made sure that it has end of line terminating resistors, and physically it looks fine. There isn't any double up station numbers, and the LINK_ID are all the same for the nodes on that network.
I am thinking that it may be because there is too much traffic on the network, and we may have to split up the network and put some nodes on the other less populated networks.
Just wondering if anyone has any ideas as what to check, or any suggestions?
Thanks,
Ken.
I'm having problems with our Citect trends from our PLCs based on our DH+ network at our workplace.
I've recently been put in charge of administrating the local PLC network and Citect system.
I am mostly self taught, but do know a reasonable amount about both, but have been stumped with the problems we are having.
Firstly our networking layout is as follows:
-Ethernet network connecting all our PCs, phones, and Control/CompactLogix PLCs and panelviews (roughly 80 PLCs), which all seem to be working fine.
-Connect to the Ethernet is 2 DHRIO cards, each with 2 DH+ channels on them. 3 of the 4 channels have no problem, but one of them is having a lot of problems with a lot of data loss on the Citect trend pages.
-Connected to the DH+ network is 2 DH+ to DH485 adapters, which the DH485 network has about 8 nodes.
The problem DH+ network has 19 nodes, 15 Allen Bradley-5/04 PLCs, 2 Allen Bradley PV-700 HMIs, and the 2 DH+ to DH485 adapters.
The total network cable length would be about 400m, and longest run would be 50m.
Citect is monitoring about 250 tags from the PLCs on that DH+ network, about 1/3 of which have a 1 second sample time, and most of the others have a 5-10 second sample time.
While monitoring the tags on Citect runtime, there seems to be periods of data loss, 5-10 mins at a time, several times an hour. It seems random, and not happening more during day or night. This doesn't happen at all on any other networks DH+ or otherwise.
Also we are trending 8 tags from the DH485 network, which have not worked since the start.
We have gone over all the connections several times, made sure that it has end of line terminating resistors, and physically it looks fine. There isn't any double up station numbers, and the LINK_ID are all the same for the nodes on that network.
I am thinking that it may be because there is too much traffic on the network, and we may have to split up the network and put some nodes on the other less populated networks.
Just wondering if anyone has any ideas as what to check, or any suggestions?
Thanks,
Ken.