HBM TIM-EC Montageanleitung Seite 44

Settings
Ф
M
(t)
42
The Units/filters menu can be used to select the unit of
measurement, decimal places and sign for the measured
quantities. You can also activate various low-pass filters
(0.1 Hz ... 3 KHz or OFF).
CASMA (Crank Angle Synchronous Moving Average)
filter
The CASMA filter is a moving average filter with low-pass
filter characteristics. The filter does not work on a time
base, in the usual way, instead it uses angular synchron­
ism, which allows an automatic response to changes in
the rotational speed. This enables the filter to eliminate
the recurrent interference occurring synchronously to the
shaft rotation and the signal is "smoothed".
For the filter to function in the TIM-EC, an angle of rota­
tion pulse is required, as well as details from the user.
The TIM-EC is fitted with an input for measuring rota­
tional speed. When a rotational speed measuring system
is connected, angle of rotation pulses (Ф) are available to
trigger the filter. Parameters transmitted over the web
interface are used for filter parameterization. For filter
operation, the size of the window, i.e. the number of
measured values to be used for averaging, must be cal­
culated.
CASMA filter
n
Fig. 10.10 Required configuration for the CASMA filter to
function
A3704-4.0 HBM: public
M
(Φ)
D
TIM-EC