OT: Brand new facility and they installed DevNet

People go with what they know, so that’s probably all he knew.

you need to stop and understang what is going on before you continue
Devicenet and DH+ are completly different networks
Devicenet is a low level network used to connect remote I/O devices to the plc
you can also connect to some panelviews it cannot connect 2 plc togethter
Devicenet has 1 master per network and that would be the plc it is also limited to 64 addresses / devices it also a very slow network
DH+ is designed to network multipule PLC's together
if I were going to redo this system is would look at moving everything over to ethernet
The may be trying to reuse a Devicenet that may have already been indtalled
keep in mind that Devicenet has long ago reached end of life and replacment parts may be limited
I hate to say this but if you don't understand the differences of the networks you may be in over your head time to call for outside help

We had (have) some GE devicenet I/O and an HMI that used to connect to a GE PLC. There were issues with the 5 remote stations at times, and we had to use Rockwell RSNetworx to interrogate the network, to find a data overlap.

The powers that be (due to cost) upgraded the PLC to ControlLogix and added a 1756-DNB card to communicate with the Devicenet remote nodes. When it works, it works, but when you disrupt it, it throws a wobbly. Sparkies were moving an HMI to another part of a desk, and somehow one of the dipswitches got set to a duplicate. Took a bit of finding for that one.
If we wanted to go from Devicenet to Ethernet for these nodes, then we need to fund and find fibre cable etc for the comms, so not going to be cheap.

As Ken says, when it is setup correctly it works. Try to add/modify something, then you could easily run into problems.

Not sure what Gary says though

keep in mind that Devicenet has long ago reached end of life and replacment parts may be limited

Click to expand...

as far as I know, still supported and parts are available, certainly on the Rockwell side.