
Input and Output Connections
AC-225 Hardware Installation and User Guide
Page 21
Figure 13: Normally Closed Supervised Input (Single Resistor)
Normally Closed Supervised Double Resistor Input Connection
Connect a 2.2K resistor in series to the input switch contacts.
Connect an 8.2K resistor parallel to the input switch contacts.
Normally Closed Supervised Input has 3 states:
•
Switch Closed - Normal State:
Loop resistance = 2.2K.
•
Switch Open – Abnormal State:
Loop resistance = 10.4K.
•
Open circuit (Infinite loop resistance) or short circuit (0 resistance)
across input terminals - Trouble State.