ADLINK EOS-1200 - Manual (Page 35)

Introduction 23
EOS-1200
1.9.2 General Purpose Digital Input (EDI)
The EOS-1200 provides 16 opto-isolated digital input channels on
the front panel. Circuitry of the isolated input channel is as follows.
As shown, signal connections for a supply and load connected to
an isolated input, here in the EOS-1200, can determine when a
load is powered. The load is connected to the power supply by a
switch and can be any DC voltage between 0 and 24 VDC. When
the switch is open, no current flows through the load and no volt-
age is applied to the load or to the EOS-1200 DI channels.
The digital logic of the EOS-1200 then registers a logic high for the
channel. When the switch is closed, current flows through the
diode and the EOS-1200 registers logic low for the channel.
Photo Coupler
DICOM
DIn
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