Siemens SIMATIC CM35, Руководство пользователя

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2-3
CM35 Counter Module
(4) J31069-D0416-U001-A5-7618
2.2 Pulse Counter
In this operating mode, the CM35 continuously counts up or down between 0
and 65535 when the counter is enabled.
-- When the counting value reaches the upper counting limit while
counting up and another pulse arrives, the counting value jumps to the
lower counting limit and counts from there without losing a pulse.
-- When the counting value reaches the lower counting limit while
counting down and another pulse arrives, the counting value jumps to
the upper counting limit and counts from there without losing a pulse.
2.3 Period Duration Measurement
In this operating mode, the CM35 acquires low frequencies with the aid of
period duration measurement.
The CM35 measures the exact time between two falling edges of the count-
ing signal by counting the pulses of an internal, precision--quartz reference
frequency.
2.4 Timer
In timer operating mode, precisely defined switch--on times of 10 millisec-
onds to 278 minutes can be implemented for every digital output.
2.5 Positioning
In this operating mode, the CM35 supports controlled positioning with a
switch--off point.
Position acquisition is performed with an incremental encoder whose pulses
are acquired by the module with the correct sign in the traversing area from
–2,147,483,648 to +2,147,483,647.
Two digital outputs are available for each of the four channels. These out-
puts are addressed by the CM35 based on the direction.
Function Description