Programmable Control Module for Digital Mass Flow Meters and Controllers

Sierra Instruments has unveiled its programmable control module, the Compod. When coupled with Sierra’s Smart-Trak mass flow meters (MFM’s) and controllers (MFC’s), the Compod simplifies basic flow control installations and permits the networking of multiple instruments using open-source MODBUS RTU protocol. By adding the Compod module to a new or existing Smart-Trak MFM or MFC, end users can take complete control. Two digital outputs and one analog input can be configured by the end user for a variety of process controls including:

Gas mixing and blending
Batch control
Leak Testing
Process monitoring
Pressure monitoring and control
Gas ratio control
Internal performance monitoring
Triggering alarms
Starting or stopping gas flows automatically under user-defined conditions
Gas flow totalization with adjustable pulse output

Compod also monitors the functionality of the mass flow meter or controller and includes diagnostics, notifying users of faults or system updates.

The Compod mounts to any Sierra Smart-Trak 100 Series, converting the instruments’ internal RS-232 communications into multi-drop RS-485/MODBUS RTU. With MODBUS, multiple instruments can be daisy-chained over a single network. When used with a PLC or master computer, each instrument equipped with Compod becomes a node on the MODBUS network, capable of sending and receiving data and commands.

Users can utilize Sierra’s provided software or write proprietary software using open-source MODBUS protocol to configure standard functions for the Smart-Trak 100 Series. Compod’s two digital input/output channels and the analog input channel and a configurable pulse output channel can automate gas processes without the need for an external PLC or computer.

Benefits of the Compod: