Dattus Model fM Commercial & Industrial Gas Meters

Dattus Model fM2 Commercial & Industrial Gas Meter The Dattus fM Meter is suited for commercial to light industrial gas measurement applications up to flow rates of 56,000 actual cubic feet per hour (acfh). With no moving parts, the Dattus Meter is ideal for applications where continuous gas flow to the customer is required. The Dattus Meter will not cause an interruption of gas service, which may be important for customers such as hospitals, nursing homes, schools, or factories using processes requiring uninterrupted gas flow.

The operation of the Dattus Meter, see diagram on following page, is based on the fluidic oscillation principle. The measurement unit is comprised of three functional elements...

Flow Conditioner
Jet Nozzle Formation
Fluidic Oscillator Chamber

Gas enters (1) the meter and divides into two separate flow paths (2) these two flows recombine (3) as they exit the flow conditioner and enter the fluidic oscillation chamber through the nozzle. The process of dividing the flows eliminates upstream disturbances and creates well-conditional flow. In the fluidic oscillation chamber, a jet is formed (4) as the gas enters through the nozzle. The jet then starts oscillating back and forth (5).

Thermal sensors, located just after the nozzle, detect a temperature variance as the gas jet passes from one side to the other. The volume of gas passed through the meter is obtained by counting the number of oscillations detected by the sensors.

Features
Construction & Specifications
Capacities
Dimensions
Accuracy, Comparison & Pressure Drop

The basic meter performs volume metering based on the gas pressure and temperature in the meter. In addition to the standard functionality of the basic configuration, we offer some options for your consideration.

Standard Features

Optional Features

Compact Design
Configurable Index Orientation
Instant Flow Rate Display
Nominal 7-10 Years Battery Life
Pressure Up to 150 psi
Capacity Up to 9,000 cfh (base rating)
Large Rangeability
Maintenance-free Operation
Two-Channel Programmable Pulse Outputs
Will Not Bind
No Oil Required
No Leveling Required
Highly Accurate Measurement
Gas Volume Totaling
Fixed Factor Correction
Non-volatile Memory for Storing Values and Data
Optical Communication Port for Reading/Writing of Values
Eight Item Programmable Display
Magnetic Switch to Change Display Values

Temperature Correction Using a Temperature Probe Mounted in the Gas Flow
Fixed Pressure Correction
Full Live Pressure and Temperature Correction and Data Logging with Integral Gas Micro EVC


Meter Pressure (PSIG)	1	5	25	60	90	100	150
MSCFH	9.6	12.0	24.3	45.7	64.0	70.1	100.6

Internal View of Dattus Model fM2 Commercial & Industrial Gas Meter

Dattus Model fM Commercial & Industrial Gas Meter Capacities


A	B	C	D	Thread Depth
16.5"	10.6"	6.75"	10.0"	1.00"

Flange Type			Bold Pattern
ANSI 125 2"			4.75"
ANSI 125 3"			6.00"

NOTE: Flanges receive four 1-3/4" x 5/8" - 11 UNC 2B Bolts

Dimensional Drawing for Dattus Model fM2 Commercial & Industrial Gas Meter

RANGEABILITY

Dynamic Range	400:1
Minimum Flow Rate	22 acfh
Maximum Flow Rate	9,000 acfh

PULSE OUTPUT

Pulse Type	Low-frequency
Form Type	A
Pulse Duration	250 ms
Pulse Value	User Scalable

TEMPERATURE PROBE

Type	PT1000, Platinum Resistance Thermistor (RTD)
Typical Accuracy	0.1% of Absolute Measurement

DATTUS ACCURACY & ROTARY METER COMPARISON

Dattus Accuracy & Rotary Meter Comparison

PRESSURE DROP, GAS (0.6 Specific Gravity) @ATMOSPHERIC CONDITIONS

Pressure Drop, Gas (0.6 Specific Gravity) @ Atmospheric Conditions

PRESSURE DROP (2" and 3" Version)

Pressure Drop (2" and 3" Version)

Download PDF Version • Download Installation Manual