Simex SLIK-638, Руководство пользователя

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User manual - COUNTER SLIK-638
To break autoscaling press [ESC/MENU] at any time. This operation causes with
restoring of all parameters “muL” , “div” and ”Point” as they was defined before
starting Autoscaling. The value of the counter is not restored.
6.4. THE DIGITAL FILTER
To enable the connection of the simple switches as detectors, special digital filter has
been build into the device. This filter allows the counter to proper counting pulses regardless of
the vibration of the contacts of the switches.
The condition of proper counting is providing of time periods of the pulses. The filter can
be set to blocking frequencies higher than 10, 20, 30, 40, 50 ,60 ,70, 80 and 90Hz. The time
periods of stable states "0" (t
0
) and "1" (t
1
) of pulses must be not shorter than 1/2F, where F
the filtered frequency in Hz. See the table below (Tab. 6.2) to check proper periods for all
frequencies.
filter setting (F) t
0
, t
1
input signal
frequency
input type
OFF
50,0
m
s /
100,0
m
s
10 kHz /
5 kHz
electronic
input
10 50,0 ms 10 Hz
20 25,0 ms 20 Hz
30 16,7 ms 30 Hz electronic
40 12,5 ms 40 Hz or contact
50 10,0 ms 50 Hz input
60 8,3 ms 60 Hz
70 7,2 ms 70 Hz
80 6,3 ms 80 Hz
90 5,6 ms 90 Hz
Tab. 6.2. Time periods t
0
,t
1
depend on filtered frequency.
When the filter is turned off , time periods t
0
i t
1
must be longer than 50
m
s (see Figure 6.4),
and maximum counted frequency is equal 10 kHz.
20
i