Siemens SIMATIC S7-300 FM 350-1, Manual

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Wiring the FM 350-1
3.1 Pin assignments of the front connector
FM 350-1 Counter module
Manual, 05/2011, A5E03648639-01
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Input Filters for 24 V Encoder Signals
For the purpose of suppressing interference, you can parameterize input filters
(RC elements) with a uniform filter time for the 24 V inputs A*, B* and N*. The following two
input filters are available.
Table 3- 2 Input Filters for 24 V Encoder Signals
Characteristics Input Filter 1
(default) Input Filter 2
Typical input delay 1 μs 15 μs
Maximum frequency of count 200 kHz 20 kHz
Minimum pulse width of the count signals 2.5 μs 25 μs
Digital Inputs DI Start, DI Stop and DI Set
You can use digital inputs DI Start and DI Stop for the gate control of the counter. Gate
control can be both level-controlled and edge-controlled (refer to the chapter Operating
Modes, Parameters and Commands (Page 83)).
Digital input DI Set is used to set the counter to the load value.
The digital inputs are operated with a nominal voltage of 24 V.
The digital inputs are optically isolated from the bus of the S7-300 and the counter inputs.
Input Filters for Digital Inputs
For the purpose of suppressing interference, you can parameterize input filters DI-Start,
DI-Stop and DI-Set (RC elements) with a uniform filter time for digital inputs. The following
two input filters are available.
Table 3- 3 Input Filters for Digital Inputs
Characteristics Input Filter 1
(default) Input Filter 2
Typical input delay 1 μs 15 μs
Maximum frequency of the input signals 200 kHz 20 kHz
Minimum pulse width of the input signals 2.5 μs 25 μs