Code Change Summary: Code language was added requiring a warning label for meter disconnect switches connected ahead of a service disconnect.
Section 230.82 spells out all of the things permitted by the NEC® to be connected ahead (on the line side) of the service disconnect. These items can remain energized even when the service disconnect for the building is shut off. Some examples include fire pump conductors, fire sprinkler alarms and meter disconnect switches.
Often, the utility company will require a disconnect switch ahead of the meter so that the lineman can open the switch to kill the load before pulling the meter. Pulling a meter under load can result in an electric arc.
If a meter disconnect is installed, it is important that it is not mistaken as a service disconnecting means. Now, field labeling is required to be located on the exterior of the meter disconnect with the words “METER DISCONNECT NOT SERVICE EQUIPMENT”.
Below is a preview of the NEC®. See the actual NEC® text at NFPA.ORG for the complete code section. Once there, click on the “free access” tab and select the applicable year of NFPA 70 (National Electrical code).
2011 Code Language:
230.82(3). Meter disconnect switches nominally rated not in excess of 600 volts that have a short-circuit current rating equal to or greater than the available short-circuit current, provided all metal housings and service enclosures are grounded in accordance with Part VII and bonded in accordance with Part V of Article 250. A meter disconnect switch shall be capable of interrupting the load served.
2014 Code Language:
230.82(3). Meter disconnect switches nominally rated not in excess of 1000 V that have a short-circuit current rating equal to or greater than the available short-circuit current, provided that all metal housings and service enclosures are grounded in accordance with Part VII and bonded in accordance with Part V of Article 250. A meter disconnect switch shall be capable of interrupting the load served. A meter disconnect shall be legibly field marked on its exterior in a manner suitable for the environment as follows:
METER DISCONNECT
NOT SERVICE EQUIPMENT
Which of the following labels is correct for a meter disconnect switch?
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