System Sensor D4120W is an InnovairFlex watertight 4-wire photoelectric low-flow duct smoke detector. Its enclosure is rated NEMA Type 4 for non-hazardous indoor and outdoor applications, so it can be mounted on rooftop HVAC equipment and in other harsh environments.
The enclosure protects against falling dirt, rain, windblown dust, splashing and hose-directed water, and the housing and cover material are UV resistant. A pivoting housing fits square and rectangular footprints and mounts to round or rectangular duct. It senses smoke at airflow of 100 to 4,000 feet per minute, -4°F to 158°F and 0 to 95% relative humidity, non-condensing. A plug-in sensor head provides false alarm immunity, and the sampling tube installs from the front or back without tools. Compared with the standard InnovairFlex unit it keeps the same form, fit and wiring terminations and adds a 3/4-inch conduit knockout, high-contrast terminal labels and short circuit protection against wiring errors.
Specifications
| Type |
Watertight 4-wire photoelectric low-flow duct smoke detector |
| Enclosure |
NEMA Type 4, indoor/outdoor |
| Supply voltage |
20-29 VDC; 24 VAC 50-60 Hz; or 120 VAC 50-60 Hz |
| Standby current |
21 mA at 24 VDC; 65 mA RMS at 24 VAC; 20 mA RMS at 120 VAC |
| Alarm current |
65 mA at 24 VDC; 135 mA RMS at 24 VAC; 35 mA RMS at 120 VAC |
| Alarm initiation contacts |
SPST, 2.0 A at 30 VDC (resistive) |
| Auxiliary contacts |
DPDT, 10 A at 30 VDC / 250 VAC |
| Air velocity |
100 to 4,000 ft/min |
| Operating temperature |
-4°F to 158°F (-20°C to 70°C) |
| Weight |
2.5 lb |
| Housing |
UL 268A certified for air handling systems |
Installation notes
-
Watertight only if installed watertight. The data sheet requires watertight conduit and fittings, with conduit holes facing down where possible. Standard fittings void the NEMA 4 protection.
-
Do not wire the auxiliary contacts to a panel initiating circuit. Use the SPST alarm initiation contact for the panel; the DPDT auxiliary contacts are for fan shutdown and similar duties.
-
Multi-fan shutdown: up to 50 D4120W units can be interconnected on the same independent supply with polarity maintained.
-
Sampling tube must match duct width: DST1 up to 1 ft, DST1.5 for 1-2 ft, DST3 for 2-4 ft, DST5 for 4-8 ft, DST10 for 8-12 ft.
- Duct detectors are not a substitute for open area smoke detection. Refer to NFPA 72 and NFPA 90A.
Related models and accessories
The D4120 is the standard, non-watertight InnovairFlex 4-wire duct detector. Accessories include the RTS151 and RTS151KEY remote test stations, RTS2-AOS multi-signaling accessory, RA100Z and APA151 remote annunciators, and the DH400OE-1 weatherproof enclosure.
