HP Performance Optimized Datacenter 20c User Guide - North America

Life safety systems 18
EPO modes
The EPO system has three operating modes:
• Armed—The EPO system is armed and operational.
• Test—The EPO system is in test mode and does not initiate during events that normally trigger an EPO.
• Bypass—The EPO system is non-operational and does not initiate during events that normally trigger an
EPO.
EPO accidental activation
To help prevent accidentally pressing the EPO button and activating the EPO system, each EPO button is
covered with a clear Lexan cover.
Battery backup during an EPO event
The following components are equipped with a UPS to help ensure that service is not interrupted during a loss
of power to the HP POD 20c:
• ECS system
• VESDA air sampling smoke detection system (on page 18)
• (Optional) fire suppression system (on page 19)
• Emergency lighting in the HP POD 20c
IMPORTANT: All Critical IT UPS devices with batteries that exceed 700VA must be connected to
the HP POD 20c EPO system, to ensure that the UPS batteries are disconnected during an EPO
event. For more information on connecting UPS devices to the EPO system, see the HP
Performance Optimized Datacenter 20c Maintenance and Service Guide.
VESDA air sampling smoke detection system
CAUTION: Excess dust within the HP POD 20c can cause the VESDA smoke detector to trigger
a fire alarm.
The VESDA system features a single zone laser scan early warning smoke detector to provide the earliest
warning of a potential fire.
The orange VESDA piping that runs throughout the HP POD 20c includes inlets for smoke sampling. The
VESDA uses a high-efficiency aspirator to continuously draw in air from the HP POD 20c and circulate the air
through a dual-stage filter:
• Stage 1—A filter removes dust and dirt from the air sample.
• Stage 2—An ultra-fine filter removes remaining contaminants in the air sample.
After the air passes through the dual-stage filter, it enters a calibrated detection chamber where a laser scans
the air sample for the presence of smoke. The VESDA system cycles through two levels if smoke is detected:
• Level 1—Smoke concentration reaches the first setpoint, and the VESDA system sends an alarm signal
indicating that a fire might exist.