ZyXEL Communications OLT2406 User Manual page 56

A closed circuit on the ALARM input pins indicates an alarm.
• Pins 14 and 15 are alarm input one.
• Pins 5 and 10 are alarm input two.
• Pins 9 and 5 are alarm input three.
• Pins 13 and 14 are alarm input four.
The ALM2406 signals an alarm when it detects an alarm on the ALARM input pins, the OLT is overheated,
the voltage readings are outside the tolerance levels a fan fails or another alarm occurs.
• To signal a critical alarm, the ALM2406 opens the circuit for pins 12 and 4 and closes the circuit for pins
8 and 4.
• To signal a major alarm, the ALM2406 opens the circuit for pins 7 and 3 and closes the circuit for pins 2
and 3.
• To signal a minor alarm, the ALM2406 opens the circuit for pins 6 and 11 and closes the circuit for pins
1 and 11.
Note: The alarm input is only for dry contact without any power.
Chapter 2 Hardware Installation
OLT2406 User's Guide
56