SPIDER 8 - Page 10

9
• To detect a situation where it is either ground or no ground, we should use a Non-isolated
GPIO input
• In a situation where we need to detect a signal, either a voltage or a ground, we should use
an Isolated GPIO input.
• We should always make use of the Isolated GPIO input common ground pin when we want
to use an Isolated GPIO input
• The voltage or ground must be recognised by the Spider GPIO interface for it to work
1.6.2. Input Signal Classification!
The following are suggested installations based on the above case numbers and associated input
signals.
Table 2: Input signal cases
Case 1:!
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Case
Input Signal
Example Input
Signal Value
GPIO Input Pin
1
Ground/Disconnect
ground/no ground
Pin 3 or Pin 4
2
Pin 9 or Pin 10
3
Pin 9 or Pin 10
4
Voltage/Ground with signal
isolation (signal separation is
done by a diode)
24V/ground
12V/ground
Pin 3 or Pin 4
5
Voltage/Ground
24V/ground
12V/ground
Pin 9 or Pin 10
6
Pin 3 or Pin 4
7
Voltage/Voltage
24V/1V, input
source voltage is
24V
Pin 9 or Pin 10
Note in this case only one isolated
input pin can be used since pin 9 and
pin 10 share the common ground pin
8.
8
Pin 3 or Pin 4
A NO (normally open) relay is
used in this case.