Labeling and Signage

Labeling shall be integrated to the individual systems and shall provide the operator an understanding of system status under cursory examination. Labeling works hand in hand with the graphical user interface (GUI) and the physical organization of the equipment and systems themselves.

The GUI is typically a visual dashboard for the complete operation of the system. Information on the GUI typically include a color -coded power flow diagram, electrical performance, electrical characteristics, and alarm status.

Equipment may have a mimic bus display, indicating how power flows through the system and how the individual breaks are connected.

It may also be color-coded for the critical, utility, and generator power systems.

A critical power system with four distinct UPS systems could be labeled UPS-A, UPS-B, UPS-C, and UPS-D. Such a system could bear a unique color-coding where the system A might be red, the B system might be blue, the C system might be green, and the D system might be yellow. This color-coding would be carried all the way through the system.

All branch and data center circuits shall be marked with their individual circuit designations.

Conduit systems and junction boxes shall also be color-coded by system, and power feeders may also bear their specific designation (e.g., UPS A Input).

Conduit color-coding may be via a label, cladding, or painting.

Circuits that are on the output of an UPS or that support critical loads should be color-coded to readily distinguish them from non-critical circuits. This color-coding may be in the form of colored self-adhesive labels or nameplates.

Equipment labeling should possess all critical information concerning the system to which it is affixed. This information should include:

• Equipment nomenclature and designation (e.g., Generator AH54)
• System capacity rating in kVA and kW (e.g., 750 kVA/675 kW)
• Input voltage, phasing, and connection (e.g., 480V, 3-phase, 3-wire)
• Output voltage, phasing, and connection (e.g., 480V, 3-phase, 3-wire)
• Power factor (e.g., 0.9 lagging)
• System or switchboard serving this piece of equipment
• System, switchboard, or load that is being served by this equipment