The Allen-Bradley 1771-CFM is a configurable flowmeter module. It is used in automated systems for the fast and accurate calculation of the flow after receiving the signal from the flow measuring field devices. It is used for shaft speed calculation too. The 1771-CFM module is the Allen-Bradley 1771 series module that makes the interface between PLCs and turbine flowmeters, magnetic pickups, or single-channel shaft encoders. It can be also used to calculate the flow signal delivered from any TTL pulse source. The Allen-Bradley 1771-CFM is used in various industries like the power generation, oil, gas, automotive, food and beverage, and pipeline industries. Operators can use it for almost any application with flow or turbine metering. By installing this module into their PLC-5 systems, users will simplify the programming and conserve memory of their PLCs. The 1771-CFM module is used as a direct replacement for 1771-QRC and 1771-QRD modules without the need for any changes to the ladder logic.

This configurable flowmeter module has four input channels and it can control up to four outputs based on the values received from the input channels. Users can select four modes of operation on this device: the non-resettable totalizer mode, totalizer mode, high-resolution frequency mode (channels 0/1 or channels 2/3), and direction sensor mode (channels 0/1 or channels 2/3). The maximum input frequency of the device is 100 kHz, the maximum count value range is 0 to 9.999.999 (programmable), and the maximum processing time is 5.5 milliseconds. The backplane power current is 1 Amp. The power dissipation ranges from 2 to 13 Watts. For diagnostic purposes, this module sends diagnostic information to the PLC processor in words that is available to programmers in a configuration block. The module should be operated at 0 to 60 degrees Celsius (32 to 140 degrees Fahrenheit) temperatures.