Which marking indicates a power-limited fire-protective signaling cable used in plenums?

Which marking indicates a power-limited fire-protective signaling cable used in plenums?

• A. FPLP
• B. FPPL
• C. PLFP
• D. PLP

Answer: (A)

The marking tested here communicates three important ratings for fire alarm cabling: fire protection, power limitation, and suitability for use in plenums. FPLP stands for Fire-Protected, Power-Limited, Plenum. The F indicates the insulation/jacket is designed to contribute to fire protection. The PL indicates the cable is power-limited, meaning it’s a low-energy signaling circuit that meets certain safety limits. The trailing P shows the jacket is plenum-rated, so the cable is approved for use in air-handling spaces like plenums where airflow is present and special fire-smoke considerations apply. So this marking confirms the cable is designed for signaling circuits (fire-protected) that are power-limited and can be run in plenums. Other markings would either miss one of these attributes or mix them in a way that doesn’t align with the standard designation.

The marking tested here communicates three important ratings for fire alarm cabling: fire protection, power limitation, and suitability for use in plenums. FPLP stands for Fire-Protected, Power-Limited, Plenum. The F indicates the insulation/jacket is designed to contribute to fire protection. The PL indicates the cable is power-limited, meaning it’s a low-energy signaling circuit that meets certain safety limits. The trailing P shows the jacket is plenum-rated, so the cable is approved for use in air-handling spaces like plenums where airflow is present and special fire-smoke considerations apply.

So this marking confirms the cable is designed for signaling circuits (fire-protected) that are power-limited and can be run in plenums. Other markings would either miss one of these attributes or mix them in a way that doesn’t align with the standard designation.