Analogue Input Spikes on Multiple Modules

[Ckyle]

Hi all,
Kyle here, working on the shop floor with a few RevPi setups. We’ve got three modules hooked up along the production line, each running 8 analogue inputs for temp and pressure. When we start scaling, some of the readings start jumping, especially on the modules further down the line… In an ideal world I’d stick to a single master module, but the Modbus bus hits saturation once we poll all inputs every 100 ms. Better to split sensors across modules or handle the spikes in software with buffers and smoothing? Signals are pretty fast, so losing data would mess with real-time reporting.
Cheers,
Kyle

[crismancich]

Hi Kyle,

can you be a bit more specific on what exactly jumping means?
Constantloy diverting temperatures? Or scatter? What are the actual values? What would you expect instead?
What type of sensors do you use? What's the cable length and sre they shielded?