The Challenge

The integrator's challenge was to quickly build a small, energy efficient controls package that could operate autonomously or while on a broad network, communicating to the operations hub over a cellular phone network.

The controls challenge requires multi-zone temperature monitoring using thermocouples and then the use of a control algorithm that could actuate either heating or cooling of the biomass to keep it at optimum temperature.

Implementation

One Soft-I/O modules was used for each of the array of biomass reactors.  Because Soft-I/O can directly connect to a thermocouple, the temperature measurement was a snap.  Soft-I/O contains the cold junction compensation as well as the linearization curves for all popular thermocouples.  Soft-I/O converts all thermocouple signals to engineering units, either degrees C, F or Kelvin.

On the actuation side, several valves are used to route heating and cooling to the biomass reactor.  With Soft-I/O's built in Soft-Devices, the entire application was done quickly.

With Soft-I/O running independently in small enclosures near the reactors, an Ethernet network was set up to allow the remote operations hub to remain in touch with any reactor over a network capable of a TCP/IP connection.  In this case, a cellular network was employed.  What's great about the Soft-I/O architecture is that the loss of a network connection does not cause the process to stop--unless that's what the user wants.