10.3.1 Communication through IS-Relay card
The UPS provides an IS-Relay card user to use dry contact signals to monitor the UPS. For the installation and use of the IS-
Relay card, refer to Vertiv™ Liebert® IntelliSlot™ IS-Relay Card User Manual.
10.3.2 Communication through dry contact port of central control module
For field specific needs, the UPS may need auxiliary connection to have functions like acquiring external equipment status
information, providing alarm signals to external devices, and remote EPO. These functions are realized through the following
interfaces on the bypass control module:
• Input dry contact port of external device status information.
• Output dry contact ports of alarm signal.
• EPO input port
For the functions and detailed information of these ports, refer to Wiring of Signal Cable on page41.
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Vertiv™ Liebert® APM2 30 to 120 kVA Modular UPS User Manual