Siemens SIMATIC S5-100U System Manual page 428

Function Modules
Function
The module consists of two independent down counters with isolated inputs and outputs. It counts
input signals up to a frequency of 500 Hz from a set value down to the value 0. When 0 is reached,
the 24-V DC output of the module is energized.
At the same time, a green LED on the module lights up and the input signal (I x.0 or I x.1) is set
to "1".
The setpoint (0 to 999) can be entered via the three-digit thumbwheel switches on the front panel of
the module.
The input voltage ranges can be set for 5 V DC or 24 V DC using rocker switches on the front
panel.
Channel 0
Channel 1
5 V DC (TTL)
Figure 15-4. Setting the Input Voltage Range on the Counter Module (500 Hz)
Installation
The counter module is plugged into a bus unit like any other module (see chapter 3).
Wiring
See schematic diagram for the counter module.
15-14
Channel 0
Channel 1
24 V DC
S5-100U
EWA 4NEB 812 6120-02b