Omega Products FMA-1601A User Manual

MASS AND VOLUMETRIC GAS FLOWMETERS

For Clean Gases

FMA-1611A includes 110 Vac
power supply and a 1.8 m (6') cable
8-pin mini DIN connector, shown actual size.

FMA-1603A includes
110 Vac power supply
and a 1.8 m (6') cable
8-pin mini DIN connector,
shown actual size.

D

FMA-1600A Series

U Ranges of 0 to 0.5 SCCM Up to 0 to 1500 SLM
U Reports Mass Flow, Volumetric Flow,

Temperature, and Pressure

U <10 ms Response Time—Field Adjustable
U 20+ Gas Calibrations, Including Air, Ar,

, CO, CO2, Ethane, H2, He, N2, N2O, Neon,

CH

4

, Propane, Butane, Iso-Butane, Acetylene,

O

2

Ethylene, Krypton, Xenon, and
Sulfur Hexafluoride

U Pressure, Temperature and, Volumetric and

Mass Flow Simultaneously Displayed

U NIST 5-Point Certificate Included
U No Straight Runs of Pipe Required
U No Warm-Up Time
U Turndown Ratio of 100:1 (1% Max Flow)
U RS232 Standard

D-X

The FMA-1600A Series mass and volumetric
flowmeters 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 5 V 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
flowmeters can be powered
by the optional battery pack
FMA1600-BP for use in the field.

SPECIFICATIONS

Accuracy: ±(0.8% of rdg

+ 0.2% FS)

Repeatability: ±0.2%
Turndown Ratio: 100:1
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 noise

Output: 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/atm
Humidity Range: 0 to 100%

non-condensing

Pressure (Max): 145 psig
Measurable Flow Rate:

125% FS
Supply 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 DIN
Wetted Parts: 302 and 303 SS,
FKM, silicone RTV, nylon
aluminum

616,

Absolute Pressure
Sensor

Exploded View of Internal
Laminar Flow Elements

Differential Pressure
Sensor

Temperature
Sensor

Dimensions: mm (inch)

Flow Range Height Length Depth Port Size

0.5 to 50 SCCM 98.98 60.33 26.67 10-32
(3.897) (2.375) (1.05) UNF

100 to 500 SCCM and 103.30 60.33 26.67 ¹⁄₈ FNPT
1 to 20 SLM (4.067) (2.375) (1.05)

50 and 100 SLM 110.92 101.60 40.64 ¹⁄₄ FNPT
(4.367) (4.0) (1.6)

250 SLM 126.16 101.60 40.64 ¹⁄₂ FNPT
(4.967) (4.0) (1.6)

500 to 1500 SLM 126.16 101.60 40.64 ³⁄₄ FNPT
(4.967) (4.0) (1.6)

D-X

Standard Pressure Drops

†

Full Scale Flow Rate psid

0.5 to 50 SCCM 1
100 SCCM to 10 SLM 1
20 SLM 1
50 SLM 2
100 SLM 2.5
250 SLM 4.0
500 SLM 5.5
1000 SLM 6.0
1500 SLM 9.0

† Venting to atmosphere.