Just to be clear, the Mobile Panel 277 is based on OP277, not MP277.I don't see how bandwidth should be a problem in this case. The units are MP277 (mobile pendant 277) and they are on ProfiNet (4 nodes - CPU, HMI, 2x IM151-3 for ET200S I/O) or in case of ProfiBus, it's 12mbps and HMI is TP177B (only three nodes - CPU, HMI, 1xCU320). The way I see it, looks like any other HMI on RS232 running on 9600 or 19.2kbps.
I only have experience with simple ethernet, not in combination with Profinet IO. With that I have only good experience. And the MP277 is to my opinion quite snappy. Changing screens is practically instant as opposed to OP177 or OP277.
For PN with PN IO. I can imagine that the bottleneck is the CPU or CP. For the PN CPUs, the CPU has to exchange the data as part of its normal cycle. So a combination of a large program and some PN IO, the performance will be penalised. In particular with the smaller 315-2PN/DP.
If a CP343-1 is used, then the explanation is the slow backplane bus of 187.5k.
edit: In your example with TP177B on Profibus, then it helps that the Profibus is fast, but it does not help that the x177 range of panels are generally very slow.
100ms must be used very sparingly.One can specify the refresh time for each tag (100ms, 1sec, etc.) but 100ms is pushing it even for few tags.
Last edited: