SENSORTECHNICS FDUM200DB

FDU Series
Mass flow sensors for gases
FEATURES
· Ranges 0...±200 sccm1
or 0...±2 "H2O (0...±5 mbar)
· Bidirectional sensing
· Actual mass flow sensing
· Low differential pressure sensing
· Sensortechnics PRO services
MEDIA COMPATIBILITY
To be used with dry gases only
The FDU series is NOT designed for liquid
flow and will be damaged by liquid flow through
the sensor
SPECIFICATIONS
ELECTRICAL CONNECTION
Maximum ratings
Supply voltage2
8 to 15 V
typ. 10 ±0.01 V
Power consumption
50 mW
Temperature limits
Operating
Storage
-25 to 85°C
-40 to 90°C
Mechanical shock
100 g (5 drops, 6 axes)
1
2
3
4
5
6
7
8
Note:
1
sccm denotes standard cubic centimeters per minute
2
Output voltage is ratiometric to supply voltage
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FDU Series
Mass flow sensors for gases
FLOW SENSOR CHARACTERISTICS3
(VS = 10 ±0.01 V, TA = 25°C)
Part no.
Flow range
(full scale)
FDUM200DB
±200 sccm
Pressure
range
±2 "H2O
FDUH002DB
Output voltage
@ trim point
Max. flow change4
5.0 l/sec
77 mV @ 200 sccm
5.0 l/sec
38 mV @ 2 "H2O
PERFORMANCE CHARACTERISTICS
(VS = 10 ±0.01 V, TA = 25°C)
Characteristics
Zero offset
Repeatability and hysteresis (combined)
Min.
Typ.
Max.
Unit
-15
0
15
mV
±0.35
%FSO
FDUM200DB
FDUH002DB
±0.1
2
Temperature effects5
Offset
-25 to 85 °C6
Span
-25 to 25 °C
FDUM200DB
FDUH002DB
25 to 85 °C
Sensor resistance (pin 1 - pin 2, pin 1 - pin 8)
±2.07
mV
-3.08
%FSO
25
5
Common mode pressure
% reading
8
FDUM200DB
±1.0
FDUH002DB
5
-30
1.5
1.75
Sensor current
Response time
% reading
±0.30
Ratiometricity error
1.0
%FSO
% reading
2.2
kOhm
0.6
mA
3.0
ms
25
p si
Notes:
2
Output voltage is ratiometric to supply voltage
3
A 5 micron filter is recommended for all devices.
4
Maximum allowable rate of flow change to prevent damage.
5
Temperature shifts in differential pressure devices are mostly due to the density change of the gas over temperature.
6
Shift is relative to 25 °C.
7
Assumes low TCR bridge resistance used (pins 2 and 8).
8
Requires recommended Rc value of 1K Ohm is used (pins 3 to 7) and typ. heater control circuit. Maximum current Rh.
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FDU Series
Mass flow sensors for gases
FLOW SPECIFICATIONS
(VS = 10 ±0.01 V, TA = 25°C)
FDUM200DB
FDUH002DB
OUTPUT VS. FLOW CURVES
FDUM200DB
FDUH002DB
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FDU Series
Mass flow sensors for gases
HEATER CONTROL CIRCUIT
SENSING BRIDGE SUPPLY CIRCUIT
6
A)
10 V
Ra
Rb
24.9 kOhm
5
7
1 kOhm
Rh
3
B)
2
24.9 kOhm
8
Rr
4
1
Note:
Circuits required for operation per specifications. Circuits are not on board the sensor.
A) Customer supplied 1 kOhm resistor (affects temperature compensation and span voltage).
B) Customer supplied 24.9 kOhm matched bridge resistors (affects null output voltage).
Output is measured differentially from pins 8 to 2.
HEATER CONTROL CIRCUIT
(suggested)
DIFFERENTIAL INSTRUMENTATION
AMPLIFIER CIRCUIT (optional)
 2 R + R1  R4 
 (V2 − V1 ) + VOffset
VO =  2
 R1  R3 
 R6 

where VOffset = VS 
 R6 + R5 
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FDU Series
Mass flow sensors for gases
OUTLINE DRAWING
13.08
(0.515)
8x3.05
(0.12)
8x0.25
(8x0.01)
7x2.54
(0.10)
15.75
(0.62)
17.02
(0.67)
1.14
(0.05)
8x0.51
(0.02)
2x Ø 1.17
(2x Ø 0.05)
1.02
(0.04)
32.39
27.94 (1.28)
(1.10)
2.79
(0.11)
13.21
(0.52)
19.3
(0.76)
2x Ø 4.70
(2x Ø0.19)
12.57
(0.50)
10.41
(0.41)
Ø 3.81
(Ø 0.15)
30.48
(1.20)
third angle projection
mass: approx. 5.6 g
dimensions in mm (inches)
GAS CORRECTION FACTORS9
Gas type
Helium (He)
Hydrogen (H2)
Argon (Ar)
Nitrogen (N2)
Oxygen (O2)
Ai r
Nitric oxide (NO)
Carbon monoxide (CO)
Methane (CH4)
Ammonia (NH3)
Nitrous oxide (N2O)
Nitrogen dioxide (NO2)
Carbon dioxide (CO2)
Correction factor (approx.)
0.510
0.710,11
0.95
1.0
1.0
1.0
1.0
1.0
1.1
1.1
1.35
1.35
1.35
Notes:
9
Gas correction factors are referenced to nitrogen (N2) as calibration gas type. Approximate gas correction factors are provided
as guidelines only. Individual gas types may perform differently at temperature extremes and varying flow rates.
10
When sensing Hydrogen (H2) or Helium (He) it may be necessary to power the mass flow sensor using increased supply voltage:
Hydrogen typ. 12 V, Helium typ. 15 V
11
Hydrogen (H2) flow measurement requires the use of a special sensor. These devices provide normal operation when sensing
hydrogen flow and are designated with an "H" at the end of the order number.
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FDU Series
Mass flow sensors for gases
ORDERING INFORMATION - AVAILABLE LISTINGS
Note:
Preferred listings are highlighted in grey
Flow range
Dry gas
±200 sccm
FDUM200DB
Pressure range
Dry gas
±2 "H2O (±5 mbar)
FDUH002DB
Sensortechnics PRO services:
· Extended guarantee period of 2 years
· Improved performance characteristics
· Custom product modifications and adaptations even for small quantities
· Advanced logistics models for supply inventory and short delivery times
· Technical support through application engineers on the phone or at your site
· Fastest possible technical response for design and QA engineers
... plus other services on request
Sensortechnics reserves the right to make changes to any products herein. Sensortechnics does not assume any liability arising out of the
application or use of any product or circuit described herein, neither does it convey any license under its patent rights nor the rights of others.
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