Specifications

Customizing and Updating the PDU
62 40kW InfraStruXure PDU—Operation and Configuration
Safety warnings
This InfraStruXure PDU and Symmetra PX UPS are provided with an Emergency Power Off switch
connection. When this EPO switch is energized, electrical power to the units is de-energized and the
system will not transfer to on-battery operation.
EPO can be achieved with either a contact closure or application of an external 24 VAC or 24 VDC
from a SELV or PELV source. It is important to note that hazardous voltage from the Mains voltage
must be isolated from the contact closure or 24 VAC, 24 VDC. The EPO circuit contact closure, the
24 VAC, or the 24 VDC is considered a SELV circuit as defined in EN 60950 Safety of Information
Technology Equipment or PELV circuit as defined in IEC 60364-4-41 Electrical Installations of
Buildings, Protection for Safety—Protection Against Electric Shock. SELV is an abbreviation for
Safety Extra Low Voltage. PELV is an abbreviation for Protective Extra Low Voltage. SELV and
PELV circuits are isolated from the Mains through a safety isolating transformer, and are designed so
that under normal conditions the voltage is limited to 42.4 Vpeak or 60 VDC.