Rosslare AC-825IP - Normally Open Supervised Single EOL Resistor Input Connection; Normally Open Supervised Double EOL Resistor Input Connection; Figure 24: Normally Closed Input Connection; Figure 25: Normally Open Supervised Input (Single Resistor)

Input and Output Connections
32 AC-825IP Hardware Installation and User Guide
Figure 24: Normally Closed Input Connection
4.1.3 Normally Open Supervised Single EOL Resistor Input
Connection
Connect an 8.2 kΩ resistor in parallel to the input switch contacts.
A Normally Open Supervised Input has 3 states:
 Switch Open – Normal State:
Loop resistance = 8.2 kΩ
 Switch Closed – Abnormal State:
Loop resistance = 0 (short circuit)
 Open circuit across input terminals – Trouble State:
Loop resistance = Infinite (open circuit).
Figure 25: Normally Open Supervised Input (Single Resistor)
4.1.4 Normally Open Supervised Double EOL Resistor Input
Connection
Connect a 2.2 kΩ resistor in series to the input switch contacts.
Connect an 8.2 kΩ resistor parallel to the input switch contacts.
A Normally Open Supervised Input has 3 states:
 Switch Open – Normal State:
Loop resistance = 10.4 kΩ
 Switch Closed – Abnormal State:
Loop resistance = 2.2 kΩ
 Open circuit (infinite loop resistance) or short circuit (0 resistance) across
input terminals – Trouble State