Input and Output Connections
AC-215IP Hardware Installation Manual
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Figure 9: Normally Open Input Connection
4.1.2
Normally Closed Input Connection
Normally Closed Input has two states:
Switch Closed – Normal State:
Loop resistance = 0 (short circuit)
Switch Open – Abnormal State:
Loop resistance = Infinite (open circuit)
Figure 10: Normally Closed Input Connection
4.1.3
Normally Open Supervised Single Resistor Input Connection
Connect a resistor of 8.2K in parallel to the input switch contacts.
Normally Open Supervised Input has 3 states:
Switch Open – Normal State:
Loop resistance = 8.2K
Switch Closed – Abnormal State:
Loop resistance = 0 (short circuit).
Open circuit across input terminals – Trouble State:
Loop resistance = Infinite (open circuit).