Advantech AIIS-1240, User Manual

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AIIS-1240 User Manual 64
C.1 Overview
Maintaining good signal connections is one of the most important factors in ensuring
that your application system is sending and receiving data correctly. A good signal
connection can avoid unnecessary and costly damage to your PC and other hard-
ware devices.
C.2 Isolated Digital I/O Connections
C.2.1 Dry/Wet Contact Support for Digital Input
Each digital input channel accepts either dry contact or 0 ~ 5 VDC wet contact inputs.
Dry contact capability allows the channel to respond to changes in external circuitry
(e.g., the closing of a switch in the external circuitry) when no voltage is present in the
external circuit. Figure 3-1 shows external circuitry with both wet and dry contact
components, connected as an input source to one of the card's digital input channels.
Figure C.1 Isolated Digital Input Connections
C.2.2 Isolated Digital Output Connections
Each of 8 isolated digital output channels comes equipped with a Darlington transis-
tor. Every 8 output channels share common collectors and integral suppression
diodes for inductive loads. Channels 0 ~ 7 use COM0, and channels 8 ~ 15 use
COM1 as a common pin. If an external voltage (5 ~ 40 V) is applied to an isolated
output channel (IDO 0 ~ IDO 15) while it is being used as an output channel, the cur-
rent will flow from the external voltage source to the card. Please take care that the
current through each GND pin not exceed 100 mA.