Mass and volumetric flowmeters

A differential pressure sensor is used to measure the pressure drop along a fixed distance of the LFE. This, along with the viscosity of the gas, is used to accurately determine the volumetric flow rate. Separate absolute temperature and pressure sensors are incorporated and correct the volumetric flow rate to a set of standard conditions.

This standardized flow rate is commonly called the mass flow rate and is reported in units such as standard cubic feet per minute or standard litres per minute. Standard units include a 0 to 5V output (4 to 20mA optional) and RS232 communications. The gas select feature can be adjusted from the front keypad or via RS232 communications.

Volumetric flow, mass flow, absolute pressure, and temperature can all be viewed or recorded through the RS232 connection.

It is also possible to multi-drop up to 26 units on the same serial connection to a distance of 38m. These flowmeters can be powered by the optional battery pack FMA1600-BP for use in the field.