LucidControl DI4/DI8, User Manual (2.0) 2018-08-04
Page 4 of 29
2.2.2 IO Connection
The LucidControl DI4/DI8 module is equipped with 4 opto-insulated and potentialinsulated inputs.
Fig. 2 shows the interconnection of the DI4 module in a typical
application.
The input signals are represented by voltage sources applying a
voltage within the valid threshold range to the inputs.
The terminals IO1, IO3, IO5, IO7 (and also IO9, IO11, IO13, IO15
for the DI8 module) are the positive voltage inputs.
The terminals IO2, IO4, IO6, IO8 (and IO10, IO12, IO14, IO16 for
the DI8 module) are the negative voltage inputs.
Fig. 3 illustrates the principle how the digital input
works. The signal applied to the terminals 1 and 2
sources an opto-coupler which insulates the electronic
of the module from the input signal.
All inputs are floating by means that they have no
common contacts (like ground) and are working
independently.
Applying a voltage above V
HighMin
between the input terminals 1 (resp. 3, 5, 7, ...) and 2
(resp. 4, 6, 8, ...) sources the LED of the opto-coupler and makes its transistor conductive
resulting in a digital HIGH state level. If the voltage is below V
LowMax
is applied this results in
a LOW state level.
All inputs are protected against overvoltage. Applying a voltage higher than
V
InMax
= 30 V may damage the input.
All inputs are protected against reverse polarity. Applying a voltage lower than –
V
InMax
= -30V may damage the input.