NEC compliance is a huge subject and covers a wide range of electrical safety standards covering the safe installation of electrical wiring and equipment . We are labeling and safety sign experts, so we'd like to look at NEC compliance from the perspective of labels and signs.
Three types of labels are required for NEC compliance:
- Arc Flash Labels
- Maximum Fault Current
- Safety labels for grid-tied photovoltaic systems
NEC Compliance - Article 110.16 (Arc Flash)
NEC article 110.16 requires that electrical equipment be field marked with arc flash labels. Here is what the NEC code states:
"Switchboards, panel boards, industrial control panels, meter socket enclosures, and motor control centers in other than dwelling occupancies, which are likely to require examination, adjustment, servicing, or maintenance while energized, shall be field marked to warn qualified persons of potential electric arc flash hazards. The marking shall be located so as to be clearly visible to qualified persons before examination, adjustment, servicing, or maintenance of the equipment."
To be NEC compliant it appears that only an arc flash warning label of some unspecified type be used. However, the footnotes of NEC 110.16 reference NFPA70E. And, although the footnotes are not a part of the code, OSHA will not consider arc flash labels fully compliant unless they meet NFPA 70E requirements. That means to be NEC compliant the label needs to contain the following information:
NEC Compliance - Article 110.24 (Available Fault Current)
NEC article 110.24 requires that electrical equipment be field labeled with the available fault current. This is a different and separate label from the arc flash label required by section 110.16. The following is what is required for NEC compliance:
NEC 110.24 Available Fault Current.
(A) Field Marking. Service equipment in other than dwelling units shall be legibly marked in the field with the maximum available fault current. The field marking(s) shall include the date the fault current calculation was performed and be of sufficient durability to withstand the environment involved.
(B) Modifications. When modifications to the electrical installation occur that affect the maximum available fault current at the service, the maximum available fault current.
Real-world advice and insight into preventing arc flash accidents.
NEC Compliance - Article 690 (Solar Photovoltaic Systems)
The third area in which labels are required for NEC compliance is on photovoltaic (PV) systems. The NEC code requires that these labels be unalterable and permanently attached to the device. What this specifically means is left to the local inspector. However, in many cases outdoor grade, permanent adhesive, vinyl labels meet these requirements.
The following sections of the NEC code require PV system labeling:
NEC 690.17 - Labeling at the DC disconnect. If a fuse or circuit breaker can be energized in either direction, that fuse or circuit breaker must be labeled as such.
NEC 690.14(C)(2) and 690.54 - The AC disconnects must be labeled with the output current and the nominal AC voltage.
If there is more than one disconnect, all disconnects must be labeled
NEC 690.53 – The following system information must be posted at the DC disconnect:
- rated maximum power-point current
- rated maximum power-point voltage
- maximum system voltage
- short-circuit current
NEC 690.5(C) – There must be a shock hazard warning at the location of the ground-fault protection.
Although not required by the NEC code, it is a good idea to place a label near the utility's meter informing them that a PV system is connected.
NEC Compliance - Where To Get Compliant Labels
Having a DuraLabel custom label printer gives you the ability to make needed labels whenever they are needed – not only for NEC compliance, but also for NFPA, OSHA, CGA, IIAR and ANSI code compliance. With over 50 types of tough-tested supplies available, DuraLabel custom label printers handle all of your compliance and safety labeling needs. Call 1-888-326-9244 today for more information about DuraLabel printers. Be sure to ask for your free sample labels.