Pressure sensors
Pressure transmitters for PCB mounting (voltage output)
AC-T series
Symbols and terms
1)
Storage temperature range Tst
A storage of the pressure sensor within the temperature range Tst,min up to Tst,max
and without applied pressure and supply voltage will not affect the performance of the pressure sensor.
2)
Operating temperature range Ta
An operation of the pressure sensor within the temperature range Ta,min up to Ta,max
will not affect the performance of the pressure sensor.
3)
Compensated temperature range Tc
While operating the pressure sensor within the temperature range Tc,min up to Tc,max
,
the deviation of the output signal from the values at 25 °C will not exceed the temperature coefficients.
Out of the compensated temperature range, the deviations may increase.
4)
Rated pressure pr
Within the rated pressure range 0 up to pr (symmetrical output: –pr up to +pr) the signal output characteristic corresponds
to this specification.
5)
6)
Overpressure pOV
Pressure cycles within the pressure range 0 up to pov will not affect the performance of the pressure sensor.
Supply voltage VCC
VCC,max is the maximum permissible supply voltage, which can be applied without damages.
VCC,min is the minimum required supply voltage, which has to be applied for normal operation.
7)
8)
Signal output current IA
IA,max is the maximum permissible sink current of the signal output.
Exceeding (e.g. short circuit) may cause irreparable damages.
DC break down voltage Vis
The pressure sensor withstands a high voltage between the stainless steel pressure connection and the electrical
connection VCC, VA and GND (all short circuited) without damage.
9)
Offset VA0
The offset VA0 is the signal output VA(p = 0) at zero pressure.
10)
Signal span (Full Scale)
Simple output: VFS = FS = VA(pr) – VA0
Symmetrical output: VFS = FS = VA(+pr) – VA(–pr)
11)
Nonlinearity L (including pressure hysteresis)
The nonlinearity is the deviation of the real sensor characteristic VA = f(p) from the ideal straight line.
It can be approximated by a polynomial of second order, with the maximum at px = pr / 2 .
The equation to calculate the nonlinearity is:
VA (px ) − VA0 px
L =
−
VA (pr ) − VA0 pr
12)
13)
Response time t10-90
Delay between a pressure change (10 ... 90% pr) and the corresponding signal output change (10 ... 90% FS).
Supply voltage rejection SVR
While varying the supply voltage within the range VCC,min up to VCC,max at constant pressure and temperature,
the signal output change will not exceed SVRmax
.
14)
15)
Temperature hysteresis
The temperature hysteresis is the change of offset, starting from the value at 25 °C after a temperature change
and return to 25 °C. Determined during temperature cycles in operating temperature range (cycles with 1 K/min).
Temperature coefficient of offset TCVA0
Offset at temperature Tx: VA0(Tx) = VA0(25 °C) + VFS(25 °C) · (Tx – 25 °C) · TCVA0
Values are valid within the compensated temperature range Tc,min up to Tc,max
Out of the compensated temperature range, the deviation may increase.
16)
Temperature coefficient of span TCVFS
Span at temperature Tx: VFS(Tx) = VFS(25 °C) · [ 1 + (Tx – 25 °C) · TCVFS
]
Values are valid within the compensated temperature range Tc,min up to Tc,max
Out of the compensated temperature range, the deviation may increase.
AS SEN PD
2009-08-03
Please read Cautions and warnings and
Page 6 of 8
Important notes at the end of this document.
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