Lot Of 2 Firewolf Advanced Photoelectric Smoke Detector, 4-Wire (FW-4)


Lot of 2 - good working condition. See photos. All terminal screws included (not shown)

The Napco 4-wire smoke detectors more accurately detect all types of fires for performance superior to previous photoelectric detectors. They come in attractive, low-profile, baseless units with dual LEDs for excellent visibility. The detectors are 100% burn-in tested Enable precision detection of even minute particles.


Low profile – only 1.8" high

4-wire model

Highly stable operation, RF/transient protection

Two built-in power/sensitivity supervision/alarm LEDs

Non-directional smoke chamber

Vandal resistant security locking feature

Built-in magnetic go/no go detector test feature

Removable smoke labyrinth for cleaning or replacement

Automatic Sensitivity window verification function meets outlined requirements in NFPA 72, Chapter 7, Inspection, Testing and Maintenance


Firewolf advanced photoelectric smoke detectors utilize two bicolored LEDs for indication of status. In a normal standby condition, the LEDs will flash green every 3 seconds. When the detector senses that its sensitivity has drifted outside the UL-Listed sensitivity window, the LEDs will flash red every 3 seconds. When the detector senses smoke and goes into alarm the status, LEDs will latch on red.

The unit is comprised of an LED light source and silicon photo diode receiving element. In a normal standby condition, the receiving element receives no light from pulsing light source. In the event of fire, smoke enters the detector and light is reflected from the smoke particles to the receiving element. The light received is converted to an electronic signal. Signals are processed in the comparator, and when two consecutive signals exceeding the basic level are received within a specific period of time, the time delay circuit triggers the SCR switch to activate the alarm signal. The status LED lights continuously during alarm period.

Technical Details


UPC: 785026033804

Light Source: Gaal As Infrared LED

Voltage: Nominal: 12 VDC or 24 VDC

Working: 8.0-35.0 VDC (35.0 VDC Max.)

Wave Form: Filtered DC 15% Ripple Max

Alarm Current: 55ma Maximum

Average Stand-by Current:

38μa Avg @ 12 VDC

55μa Avg @ 24 VDC

70μa Avg @ 35 VDC

Ambient Temperature: 32°F - 120°F (0°C - -49°C)

Engineering Specifications

Detector head UL-listed compatible with a UL-listed fire alarm panel

Flashing status LED for visual supervision. When the detector is actuated, the flashing LED latches on steady at full brilliance. The detector may be reset by actuating the control panel reset switch.

Sensitivity window verification feature.

Vandal resistant, field selectable, security locking feature

Smokeless testing method simulates the effects of products of combustion in the chamber to ensure testing of detector circuits.

Voltage and RF transient suppression techniques to minimize false alarm potential.