Averaging; Automatic Zero Mode - Pepperl+Fuchs 3RG7256-3NQ00-PF Instructions De Service Et De Montage

Mounting and
operating instructions

Averaging

The measuring result (output signal) is smoothed by averaging. The measured values are read continuously into a
memory and the arithmetical mean is formed. Functions 14 and 15 ( (page 33) determine the number of measure­
ments (10 or 100) to be used for averaging.
With a scanning rate of 0.4 ms per measurement, the response time lies between 0.4 ms (without averaging) and 40
ms.
Example of use: When measuring rough surfaces, it is possible to counter-balance fluctuations in measured values.
Response time
0.4 ms = measured value (no average)
4 ms = averaging with 10 measured values
40 ms = averaging with 100 measured values

Automatic zero mode

The output characteristic curve 4 – 20 mA is displaced with this function. When the automatic zero mode is activated
, the current measured value is equated with the output value of 0% = 4 mA. The incline of the cha­
and Q = +U
1 B
racteristic curve is maintained and the minimum and maximum values of the characteristic curve are limited by the
measuring range.
The distance to the object must be within the measuring range.
Analogue signal
100% (20 mA)
50% (12 mA)
0% (4 mA)
+U
B
Q
1
­U
B
Illustr. 11
15500148
3RG7256­3NQ00­PF Distance sensor ­ 068­13787 / 45­3489 ­ Stand: 03/2011
I(mA)
Illustr. 10 Output characteristics in relation to arithmetical mean
15500155
100% (20 mA)
0% (4 mA)
t(s)
Illustr. 12
15500147
Direction of movement
Response time t(s)
250 400
Measuring object
Factory setting
Autom. zero at 400 mm
mm
750
35