sebastianp
Lifetime Supporting Member
Hi all,
We have a small devicenet network running for more then 4 years without a single problem.
CompactLogix+1769SDN scanner
nodes 1,2,3 = PowerFlex 700
nodes 4,5 = PowerFlex 755
node 6 = D0-Devnets.
All connected in same order. Thin cable, good resistors, length < 70 feet, power supply only for network.
Out of blue, node 3 decided to cycle between online/offline therefore drive associated stopped.( is commanded over port 5 - 20-COMM-D ) creating havoc on production people
In 10 minutes I put drive on manual , cancelled port 5 command, started local from pushbuttons with freq change possible also from pushbuttons.
Now I'm waiting clearance to stop all to be able to play with Interscan Delay. Now it's minimum 10 ms, baudrate 125k.
Until then I'm trying to understand why node 3 got that behaviour.
We forgot yesterday AC off, drive 3 having at stop moment 86degC on IGBT. Inside room about 42degC.
I started back AC, today having 64degC on drive and 30DegC inside room, and 20-COMM-D all solid green.. hmm
Can temperature influence behaviour of 20-COMM-D ?
Morevoer started to monitor the network with DeviceNet Traffic Analyzer connected over 1784-PCD card.
I do not know all dnet under the hood frames, but at least can look at statistics.
And : I saw lots of group 3 frames going to nodes 4,5 less to 1,2 and slightly more to node 3. Node 6 no group 3 frames.
: on interpreted data showing lots of UCMM going to node 1,2,3 but also to nodes 38-61 .... hmmm again
In plc I have not explicit messages, I am using only polled I/O.
So, where these UCMM and explicit messages comes from?? And more why they are going to nonexistent nodes?
I have attached some printscreens and interpreted data.
Any thoughts on this? and what to do to get to the bottom of cycling on/off?
First thing I will do when possible is play with Interscan Delay, baudrate and also heat the 20-COMM-D to over 50DegC to see what happens ( book says operating 10-50degC, but in past there were times with environment 45degC and IGBT 100 and nothing happened )
We have a small devicenet network running for more then 4 years without a single problem.
CompactLogix+1769SDN scanner
nodes 1,2,3 = PowerFlex 700
nodes 4,5 = PowerFlex 755
node 6 = D0-Devnets.
All connected in same order. Thin cable, good resistors, length < 70 feet, power supply only for network.
Out of blue, node 3 decided to cycle between online/offline therefore drive associated stopped.( is commanded over port 5 - 20-COMM-D ) creating havoc on production people
In 10 minutes I put drive on manual , cancelled port 5 command, started local from pushbuttons with freq change possible also from pushbuttons.
Now I'm waiting clearance to stop all to be able to play with Interscan Delay. Now it's minimum 10 ms, baudrate 125k.
Until then I'm trying to understand why node 3 got that behaviour.
We forgot yesterday AC off, drive 3 having at stop moment 86degC on IGBT. Inside room about 42degC.
I started back AC, today having 64degC on drive and 30DegC inside room, and 20-COMM-D all solid green.. hmm
Can temperature influence behaviour of 20-COMM-D ?
Morevoer started to monitor the network with DeviceNet Traffic Analyzer connected over 1784-PCD card.
I do not know all dnet under the hood frames, but at least can look at statistics.
And : I saw lots of group 3 frames going to nodes 4,5 less to 1,2 and slightly more to node 3. Node 6 no group 3 frames.
: on interpreted data showing lots of UCMM going to node 1,2,3 but also to nodes 38-61 .... hmmm again
In plc I have not explicit messages, I am using only polled I/O.
So, where these UCMM and explicit messages comes from?? And more why they are going to nonexistent nodes?
I have attached some printscreens and interpreted data.
Any thoughts on this? and what to do to get to the bottom of cycling on/off?
First thing I will do when possible is play with Interscan Delay, baudrate and also heat the 20-COMM-D to over 50DegC to see what happens ( book says operating 10-50degC, but in past there were times with environment 45degC and IGBT 100 and nothing happened )