After a piece of electrical equipment or device is tested and/or calibrated, a color-coded decal should be attached on the exterior enclosure to that particular equipment. Photo: TestGuy.
Test decals are an important part of any electrical maintenance program, they provide immediate indication of the last maintenance date and the overall condition of the specific devices that have been tested and maintained in the field.
This can assist employees in the assessment of the overall electrical equipment maintenance status.
Field testing labels help satisfy documentation requirements of NFPA 70E-2015, which specifies that the equipment owner is responsible for electrical equipment maintenance and the documentation of such maintenance.
The 2015 edition of NFPA 70E standard added IEEE 3007.2 Recommended Practice for the Maintenance of Industrial and Commercial Power Systems as a guideline for maintenance frequency, methods, and tests, along with NFPA-70B and ANSI/NETA MTS.
NFPA 70B, Recommended Practice for Electrical Equipment Maintenance, specifies that after a piece of electrical equipment or device is tested and/or calibrated, a color-coded decal should be attached on the exterior enclosure to that particular equipment.
The decal should include the following:
- Date of test or calibration
- Person or outside company who performed the testing or calibration
- Color coding indicating the service classification as described in 11.27.3.
Red (Non-serviceable) - Device has a problem detrimental to its proper electrical or mechanical operation such as no trip on one or more phases or high contact resistance readings. This device should not be placed back into service.
Yellow (Limited Service) - Device has a minor problem that does not impact equipment serviceability but should be fixed as soon as possible. Some examples of minor problems include slightly lower than acceptable insulation resistance readings or chipped arc chutes.
White (Servicable) - Device is electrically and mechanically sound and suitable for service but may still have minor defects such as slight corrosion or incorrect circuit ID.
ANSI/NETA ATS also specifies the requirements for field testing labels in Section 5. It’s easy to see that the requirements found in this standard have been adopted from those found in NFPA 70B.
The testing organization shall affix a test decal on the exterior of equipment or equipment enclosure of protective devices after performing electrical tests.
The test decal shall be color-coded to communicate the condition of maintenance for the protective device. Color scheme for condition of maintenance of overcurrent protective device shall be:
- White: electrically and mechanically acceptable.
- Yellow: minor deficiency not affecting fault detection and operation, but minor electrical or mechanical condition exists.
- Red: deficiency exists affecting performance, not suitable for service.
The decal shall include: Testing organization, Project number, Test date, and Technician name.