521NCRXT Edwards 2-Wire Smoke Detector (Fixed/ROR)

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  • Refine Search: Fire Safety
  • Product Type: Smoke Detectors
  • Operating Temperature: 32 to 100° F
  • Operating Voltage: 12/24VDC
  • Weight: 0.45 lb
521NCRXT Edwards Signaling 500 Series 2-Wire Smoke Detector (Fixed/ROR), 12/24VDC operating voltage,32 to 100 F operating temp white, with fixed temp and ROR heat, aux relay.

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Product Description

521NCRXT Edwards two-wire conventional photoelectric smoke detectors work on a light-scattering principle. A pulsed infrared light-emitting diode serves as the light source, and a high-speed photo diode as the sensing element. This design protects against nuisance alarms caused by dust, insects, RF interference, and ambient light. Built-in drift compensation allows the detector to automatically adjust its sensitivity over time as it becomes dirty.

The optical chamber is field replaceable. In the event of a confirmed alarm the LED will light continuously. The unit indicates trouble by flashing the LED every second. This meets the NFPA 72 field sensitivity testing requirements.

The offers sounders in two-wire applications, specifically to meet residential code requirements. Units with built-in 85dBA sounders emit a temporal 3-3-3 tone pattern when in alarm and will emit a steady tone when the input power is reversed. All wiring terminates in clamp-type screw terminals. The detectors mount to a standard single-gang electrical box, a four-inch octagonal, four-inch square electrical box, or WIREMOLD No. 5739 fixture box.


Dimension Drawing

kidde  photoelectric smoke detector dimensions