American Power Conversion PD150G6F - Manual (Page 11)

Safety: Warnings
150kW InfraStruXure PDU—Operation and Configuration 3
Total power off procedure
1. Set the PDU Main Input switch to OFF.
2. Set the upstream circuit breaker of the power source to OFF.
Emergency Power Off (EPO)
Hazardous voltage from the branch circuit must be isolated from the 24VAC, 24VDC, and contact
closure. 24VAC and 24VDC are considered Class 2 circuits as defined in Article 725 of the National
Electrical Code (NFPA 70) and Section 16 of the Canadian Electrical Code (C22.1).
A Class 2 circuit is a source having limited voltage and energy capacity as follows:
a. If an Inherently Limited Power Source, voltage and energy are limited to less than 30VAC,
less than 30VDC, and 8A.
b. If not an Inherently Limited Power Source, voltage and energy are limited to less than
30VAC, less than 60VDC, 250VA, and the current is limited to 1000/Vmax. The fuse is
limited to 5A if less than 20VAC or 20VDC, or 100/Vmaximum if less than 30VAC or
60VDC.
If you choose to use a 24VAC, 24VDC, or contact closure connection to the EPO, use one of the
following UL-listed wire types:
• CL2 Class 2 cable for general purpose use
• CL2P Plenum cable for use in ducts, plenums, and other space used for environmental air
• CL2R Riser cable for use in a vertical run shaft from floor to floor
• CL2X Limited Use cable for use in dwellings and for use in a raceway
• For installation in Canada, the cable should be CSA Certified, type ELC (extra-low-voltage
control cable).
If you do not use a CL2 cable, route the EPO wiring in conduit that does not contain any branch
circuit wiring.