Advantech Carbon Monoxide Alarm PCI-1718 Series User Manual
PCI-1718 Series User Manual
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3.3.2 Analog Input Connections
PCI-1718HDU/HGU supports either 16 single-ended or 8 differential
analog inputs. Switch SW2 selects the input channel configuration.
analog inputs. Switch SW2 selects the input channel configuration.
Single-ended Channel Connections
Single-ended connections use only one signal wire per channel. The volt-
age on the line references to the common ground on the card. A signal
source without a local ground is called a "floating" source. It is fairly sim-
ple to connect a single ended channel to a floating signal source. A stan-
dard wiring diagram looks like this:
Single-ended connections use only one signal wire per channel. The volt-
age on the line references to the common ground on the card. A signal
source without a local ground is called a "floating" source. It is fairly sim-
ple to connect a single ended channel to a floating signal source. A stan-
dard wiring diagram looks like this:
Differential Channel Connections
Differential input connections use two signal wires per channel. The card
measures only the voltage difference between these two wires, the HI
wire and the LOW wire. If the signal source has no connection to ground,
it is called a "floating" source. A connection must exist between LOW
and ground to define a common reference point for floating signal
sources. To measure a floating sources connect the input channels as
shown below:
Differential input connections use two signal wires per channel. The card
measures only the voltage difference between these two wires, the HI
wire and the LOW wire. If the signal source has no connection to ground,
it is called a "floating" source. A connection must exist between LOW
and ground to define a common reference point for floating signal
sources. To measure a floating sources connect the input channels as
shown below:
Signal Input
+
Vs
-
A.GND
A.GND
A.GND
To A/D
+
-
HIGH
LOW
A.GND
+
Vin
-
+
Vs
-