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3 analog input connections, Figure 3.2: differential input channel connection, 4 isolated digital input connections – Advantech 4718 User Manual

Page 35: Figure 3.2:single-ended input channel connection, Isolated digital input connections

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Chapter 3

3.3 Analog Input Connections

The differential input channels operate with two signal wires for each
channel, and the voltage difference between both signal wires is mea-
sured. There are 8 analog input channels available on USB-4718

Figure 3.2: Differential Input Channel Connection

3.4 Isolated Digital Input Connections

USB-4718 has 8 isolated digital input channels designated IDI0~IDI7.
Each of isolated digital input channel accepts 5~30 VDC voltage inputs,
and accept bi-directional input. It means that you can apply positive or
negative voltage to an isolated input pin (IDI). All 8 input channels share
one common pin. Figure 3-3 shows how to connect an external input
source to one of the module’s isolated input channels