AWM42000 Series
Mass flow sensor for gases
FEATURES
· Ranges 0...±25 and 0...±1000 sccm
1
· Bidirectional sensing
· Actual mass flow sensing
· Ceramic flow tube
· Manifold mount/o-ring sealed
SERVICE
To be used with dry gases only.
The AWM42150VH is a special sensor for
hydrogen (H
2
) flow.
The AWM series is NOT designed for liquid
flow and will be damaged by liquid flow through
the sensor.
SPECIFICATIONS
Maximum ratings
Supply voltage
2
8 to 15 V
typ. 10 ±0.01 V
max. 60 mW
ELECTRICAL CONNECTION
P1
P2
Power consumption
Temperature limits
Operating
Storage
Mechanical shock
-40 to 125°C
-40 to 125°C
100 g (5 drops, 6 axes)
1 2 3 4 5 6
Note:
1
sccm denotes standard cubic centimeters per minute
2
Output voltage is ratiometric to supply voltage
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AWM42000 Series
Mass flow sensor for gases
FLOW SENSOR CHARACTERISTICS
3
V
S
= 10 ±0.01 V, T
A
= 25°C
Part no.
AWM42150VH
AWM42300V
Flow range
(full scale)
± 2 5 sccm
± 1 0 0 0 sccm
Max. flow
ch an g e
4
5.0 l/sec
5.0 l/sec
Output voltage
@ trim point
8.5 ±1.5 mV @ 25 sccm
54.7 ±3.7 mV @ 1000 sccm
PERFORMANCE CHARACTERISTICS
V
S
= 10 ±0.01 V, T
A
= 25°C
Characteristics
Zero offset
AWM42150VH
AWM42300V
Repeatability and hysteresis
(combined)
Temperature effects
5
Offset
Span
-25 to 85 °C
-25 to 25 °C
25 to 85 °C
Response time
Common mode pressure
AWM42150VH
AWM42300V
Min.
-1.0
-1.5
Typ.
0
0
Max.
1.0
1.5
±0.35
±0.50
Unit
mV
% reading
mV
% reading
±0.20
2.5
-2.5
1.0
3.0
150
ms
p si
Notes:
3
A 5 micron filter is recommended for all devices.
4
Maximum allowable rate of flow change to prevent damage.
5
Shift is relative to 25 °C.
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AWM42000 Series
Mass flow sensor for gases
OUTPUT FLOW VS INTERCHANGEABILITY
V
S
= 10 ±0.01 V, T
A
= 25°C
OUTPUT CURVES
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AWM42000 Series
Mass flow sensor for gases
HEATER CONTROL CIRCUIT
SENSING BRIDGE SUPPLY CIRCUIT
Note:
Circuits required for operation per specifications. Circuits are not on board the
sensor.
DIFFERENTIAL INSTRUMENTATION AMPLIFIER CIRCUIT (OPTIONAL)
2
R
+
R
1
R
4
(
V
2
−
V
1
)
+
V
Offset
V
O
=
2
R
R
1
3
R
6
where
V
Offset
=
V
S
R
+
R
5
6
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November 2004 / 624
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AWM42000 Series
Mass flow sensor for gases
OUTLINE DRAWING
30.5
(1.20)
27.7
(1.09)
14.0
(0.55)
32.2
(1.19)
7.62
(0.30)
6 5 4 3 2 1
0.64
(0.025)
2.5
(0.10)
34.0
(1.34)
3.0
(0.12)
17.3
(0.68)
10.9 8.4
(0.43) (0.33)
Ø 6.2
(Ø 0.24)
Ø 3.51
(Ø 0.138)
4.8
(0.19)
Ø 3.0
(Ø 0.12)
P1
P2
Ø 2.0
(Ø 0.08)
2.54
(0.10)
7.9
(0.31)
12.7
(0.50)
1 2 3 4 5 6
mass:
approx. 14 g
dimensions in mm (inches)
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