Specifications
AS-Interface Slaves
Modules with special functions
Counter modules
6/108
Siemens IK PI · 2009
6
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Overview
This module is used to send hexadecimal coded count values
(LSB=D0, MSB=D3) to a higher-level controller. The count value
is increased by one for each valid count pulse at terminal 8.
Beginning at 0, the module counts up to 15 and then begins
again at 0. The controller adopts the current value and deter-
mines the number of pulses between two host invocations
through subtraction from the previous value. The total number
of count pulses is determined by adding these differences.
For the values sent to be unambiguous, no more than 15 count
values are allowed between two host invocations or AS-Interface
master invocations at terminal 8. The maximum permissible
transmission frequency is calculated from these times:
f
TRmax
= 15 / T
max
T
max
: max. possible transmission time from the slave to the host
Another condition for the maximum frequency is the pulse
shaped required. For the counter to accept a pulse as valid, a
Low must have been applied at the input for at least 300 µs and
a High for at least 1 ms. This results in a controller-independent
maximum frequency of
f
Zmax
= 1 / 1.3 ms = 769 Hz for the counter module
(see following graphic).
If the time criterion stipulated in the graphic is violated, the count
value is rejected.
The counter is active only for the reset parameter P2 (default).
The counter is deleted when P2 is set, and the incoming count
pulses are not registered until after P2 is reset again.
Note:
A customized function block is necessary or must be
programmed.
Connection options
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Selection and ordering data
N S A 0 0 0 8 4
7
I N 1
³
1 m s
³
3 0 0 s
J
NSA0_00085
IN1
ASi
ADDR
ASi+ ASi-
IN1 -
+
Terminal 4: Bus connection ASi+
Terminal 5: Bus connection ASi-
Terminal 6: unused
Terminal 7: Sensor supply+
Terminal 8: Counter input
Terminal 9: Sensor supply-
Version Order No.
3RK1 200-0CE03-0AA2
3RK1 200-0CG03-0AA2
• Counter module
• With screw terminal connection
3RK1 200-0CE03-0AA2
• With spring-loaded terminal connection
3RK1 200-0CG03-0AA2