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Monday, February 18, 2019
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TOTEM Finite State Machine Information - Reading from a Input Register
I have been given a datasheet for a CHP unit. I am looking how I can get the multistates?


I have a AO Smith / TOTEM CHP Unit, and we are interfacing with TCP/IP Modbus. I have all the values I would like to pick up (Flow & Return, Hours run etc) but there is a section named TOTEM finite state machine information. The input register is number 38 but it looks like a BACnet multistate module, but unable to use these in Modbus?

Here's an example

#3 - Engine Starting

#1 - Fault Check
#2 - IEEE waiting time when the mains if off
#3 - Reset step motor position

How can I read these? I am using OpenSystem Solutions Broadsword. I have the options to send it an offset, slave, format & scale and readback an analogue output.