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Description of commands
NDRA91-92
Manual
LDM301-302 Manual
Page 64
ASTECH GmbH
The duration of the measurement depends on the number of the set
measurement values SA and the set measurement frequency MF.
For the output of the speed measurement data, at least 9 valid distance
measurements are necessary. If a distance value is output additionally, this
value always denotes the first valid distance value that was used for the speed
calculation.
VT – Continuous speed measurement
The
NDRA91
carries out a continuous measurement. From 25 single
measurements, the speed value is calculated. The continuous speed
measurement can be stopped with the command (RS-232/RS-422: Escape =
0x1B).
The interval between the single measurements depends on the set
measurement value SA and the set measurement frequency MF.
The precision of the speed measurement is derived from the following
formula:
𝜎
𝑣
= 𝜎
𝑑
∗
𝑓
𝑁 ∗ √𝑁
∗
1
√1300
The following parameters apply:
f
Measurement frequency (Parameter MF)
N
Average value (Parameter SA)
σ
d
Standard deviation distance measurement (single shot without
averaging)
σ
v
Standard deviation speed measurement
The duration of speed measurement amounts to:
𝑡 =
25 ∗ 𝑁
𝑓
Assuming the standard deviation of
σ
d
= 3cm for a single distance
measurement, the following table results:
Содержание NDRA91
Страница 1: ...Manual NDRA91 92 Firmware Version from 1 5 Version 2 0 ...
Страница 41: ...NDRA91 92 Manual Interface description NADO Page 41 Figure 17 Example of switching output wiring ...
Страница 43: ...NDRA91 92 Manual Interface description NADO Page 43 Figure 20 Wiring analog output QA of NDRA91 ...
Страница 90: ...Notice NDRA91 92 Manual Page 90 NADO ...
Страница 91: ...NDRA91 92 Manual Notice NADO Page 91 ...