Advantech AIIS-3400, User Manual

Page: 84 / 90

AIIS-3400/3410 User Manual 72
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 0Vdc - 5Vdc 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 pres-
ent in the external circuit. Figure C-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 (5Vdc - 40Vdc) is applied to an iso-
lated output channel (IDO 0 ~ IDO 15) while it is being used as an output channel, the
current will flow from the external voltage source to the card. Please take care that
the current through each GND pin not exceed 100 mA.