View Single Post
Old February 9th, 2018, 07:09 PM   #5
sparkie
Lifetime Supporting Member
United States

sparkie is offline
 
Join Date: Nov 2014
Location: KS
Posts: 811
Thanks for the info. I'm about to wrap up for the day. Gotta love laying out terminal blocks by hand

To be more specific:

Process Controller:
Handle Valve action with P control (2-3 degree + or - for a given set point)
Allow changing of the Setpoint at the station
4-20mA output for temperature (to reduce load on RS-485 Network)

PLC:
Write to setpoint and deadband from a parallel HMI and SCADA
Read the value of a flow switch
Provide the alarming
Integrate with the glycol chilling units

I'm not sure on the PLC yet, as I'm not that far into it. I was thinking about using a Click PLC to read the modbus values for alarming and to interface with the SCADA and HMI, and at first I will likely just connect the PLC to the RS-485 network, as it will only be used to start and stop the glycol chillers at the moment so that we can get him up and running by April.

Eventually I'll be pumping all this data into their process tracking software, hence the reason I want to put each group of tanks on a gateway.
  Reply With Quote