Installation
2.3.1 Digital/Pulse inputs
The WL-TX-900 module provides two digital inputs suitable for:
Voltage free contacts – e.g. mechanical switches; or
NPN transistor devices – e.g. electronic proximity switches; or
0-5V signals.
Note: PNP transistor devices are not suitable.
The unit provides contact wetting current of approximately 5mA to maintain reliable
operation of driving relays. To activate the digital input, the switching device resistance
must be less than 200 ohms.
Each digital input circuit includes a LED indicator that lights when the digital input is
active (i.e. when the input circuit is closed).
The WL-TX-900 module lets you configure the digital inputs as pulse inputs with the
following characteristics:
Characteristic
Value
Maximum rate
10 Hz
Minimum off time
20 mSec
Minimum on time
20 mSec
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