Contrec 405

Frequency Input Flow Computer (Optional EXD)

The 405 Flow Computer can handle a wide range of flow applications, where high accuracy and flexibility are required. It will interface to most flowmeters and versions are available for pulse and analog inputs.

Either the Flow Rate or a Resettable Total can be continuously displayed in engineering units on the large six digit LCD display. A non-resettable Accumulated Total is also displayed whenever the DISPLAY key is pressed.

A scaled pulse output, suitable for driving remote totalisers is a standard feature and the instrument also provides an 8-24 Volts dc power supply for driving transducers.


Optional features include: an isolated 4-20mA output; a communications interface; and high/low flow rate alarms which are output on two Form C relays.

The communications option includes both RS232 and RS422/485 interfaces for communicating with a computer.

Software drivers are also included for a number of printers and can print a ticket with time and date, a sequential ticket number, and the resettable and accumulated totals.


The 405 is initially set-up by following a calibration sequence that enables scaling factors, digital filtering and display formatting to be set and stored in a non-volatile memory which does not require battery backup.

The instrument will operate from 12 to 28V dc or from the 110/220V ac mains.

Each flow computer is supplied with a sheet of self-adhesive engineering unit labels. A recess, adjacent to the display, is provided in which the correct label can be placed.