Mass and volumetric flow meters FMA-1600A

The FMA-1600A Series mass and volumetric  flow meters use the principle of differential pressure within a laminar flow field to determine the mass flow rate. A laminar flow element (LFE) inside the meter forces the gas into laminar (streamlined) flow. Inside this region, the Poiseuille equation dictates that the volumetric flow rate be linearly related to the  pressure drop. 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 (SCFM) or standard liters per minute (SLM).Standard units include a 0 to 5V output (4 to 20 mA 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 38 m (125'). These flow meters are available in a portable version (“-B” option), the battery charge will last up to 18 hours.

Specifications

Accuracy: ±(0.8% of rdg + 0.2% FS)

Repeatability: ±0.2%Turndown

Ratio: 200:1

Response Time: 10 ms typical default response time for 63.2% of a step change.

A variable register allows response time to be field adjustable to a certain extent via RS232  communications.

The primary trade-off for response time is signal noiseOutput: 0 to 5 Vdc standard

Operating Temperature: -10 to 50°C (14 to 122°F)

Zero Shift: 0.02% FS/°C/atm

Span Shift: 0.02% FS/°C/atmHumidity

Range: 0 to 100% non-condensingPressure (Maximum): 145 psigMeasurable

Flow Rate: 125% FSS

upply Voltage: 7 to 30 Vdc (15 to 30 Vdc for  4 to 20 mA output)

Supply Current: 35 mA typical current draw; 100 mA  available supply recommended

Cable Connection: 8-pin mini DINWetted

Parts: 302 and 303 SS, FKM, heat cured silicone RTV, glass reinforced PPS, heat cured epoxy, aluminum, gold, brass, 430 FR stainless (416 stainless steel on large sizes), silicon, glass