NOTIFIER FST-851 — an intelligent plug-in thermal (heat) detector with FlashScan, providing 135°F (57°C) fixed-temperature detection. It must be mounted to a separate base, ordered separately.
The FST-851(A) Series uses an innovative thermistor sensing circuit for fast response in a low-profile package, and integral communications give it features that surpass conventional detectors. Point ID capability allows each detector’s address to be set with rotary decimal address switches, providing exact detector locations. Two bi-color LEDs give a 360° field viewing angle — blinking green in normal condition and turning steady red in alarm. Thermal detectors are used for the protection of property rather than life safety, which makes them the right choice in areas where smoke detection would be prone to nuisance alarms. The detector plugs into a separate base that carries the SEMS-screw field wiring, and the same base accepts photoelectric, ionization and thermal sensors interchangeably. FST-851(A) Series detectors are compatible with NOTIFIER ONYX and CLIP series fire alarm control panels.
Specifications
| Type |
Intelligent plug-in thermal (heat) detector, fixed temperature |
| Thermal rating |
Factory preset fixed-temperature setpoint 135°F (57°C) |
| Protocol |
Compatible with FlashScan and CLIP protocol systems |
| Addressing |
Rotary, decimal addressing — 1–99 on CLIP systems, 1–159 on FlashScan systems |
| SLC connection |
Two-wire |
| Voltage range |
15 – 32 volts DC peak |
| Standby current (max. avg.) |
300 µA @ 24 VDC (one communication every 5 seconds with LED enabled) |
| LED current (max.) |
6.5 mA @ 24 VDC (“ON”) |
| Operating temperature range |
FST-851(A) Series: -20°C to 38°C (-4°F to 100°F) |
| Relative humidity |
10% – 93% non-condensing |
| Detector spacing |
UL approved for 50 ft. (15.24 m) center to center; FM approved for 25 x 25 ft. (7.62 x 7.62 m) spacing |
| Size |
2.1 in. (5.3 cm) high; base determines diameter — B210LP(A) 6.1 in. (15.5 cm), B501(A) 4.1 in. (10.4 cm), B200S(A)/B200SR(A) 6.875 in. (17.46 cm), B224RB(A)/B224BI(A) 6.2 in. (15.748 cm) |
| Shipping weight |
4.8 oz. (137 g) |
| Construction |
Off-white fire-resistant plastic; 94-5V plastic flammability rating |
| Agency listings |
UL S747; ULC S6978; MEA 383-02-E; FM Approved; CSFM 7270-0028:0196; BSMI CI313066760025; CCCF Certif. # 2004081801000018; U.S. Coast Guard 161.002/42/1 and 161.002/50/0; Lloyd’s Register 11/600013 |
| Country of origin |
Made in the U.S.A. |
Installation notes
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Fixed temperature only: the plain FST-851 is the 135°F (57°C) fixed-temperature model. Rate-of-rise detection at 15°F (8.3°C) per minute is the FST-851R, and 190°F (88°C) high-temperature detection is the FST-851H — do not substitute one for another on a submittal.
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Base sold separately: the detector must be mounted to one of the intelligent bases. Mount the base on an electrical backbox at least 1.5 in. (3.81 cm) deep; for a chart of compatible junction boxes see DN-60054.
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No end-of-line resistor: because of the supervision inherent in the SLC loop, end-of-line resistors are not required. Wiring “T-taps” or branches are permitted for Style 4 (Class B) wiring.
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Isolator limits: when using relay or sounder bases, consult the ISO-X(A) installation sheet I56-1380 for device limitations between isolator modules and isolator bases. The B224BI(A) isolator base allows a maximum of 25 devices between isolator bases.
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Marine listings exclude one base: the U.S. Coast Guard 161.002/50/0 and Lloyd’s Register 11/600013 listings for NFS2-640/NFS-320/NFS-320C exclude the B210LP(A) base.
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High-ceiling maintenance: the XR2B removal tool with XP-4 extension poles allows detector heads to be installed or removed without a ladder. Functional testing uses the M02-04-00 test magnet or the M02-09-00 telescoping version.
Related models
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FST-851A — same detector with ULC listing (the “A” suffix indicates the ULC listed model).
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FST-851R / FST-851RA — intelligent thermal detector adding the rate-of-rise feature, 15°F (8.3°C) per minute.
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FST-851H / FST-851HA — intelligent high-temperature thermal detector fixed at 190°F (88°C), with a wider operating range of -20°C to 66°C (-4°F to 150°F).
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FST-951 Series — the later generation of NOTIFIER intelligent heat detector, covered by its own data sheet; it is a different product from the FST-851 Series and uses the newer base range.
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B210LP(A) / B501(A) / B200S(A) / B200SR(A) / B224RB(A) / B224BI(A) — standard flanged, flangeless, sounder, retrofit sounder, relay and isolator bases.
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RA100Z(A) — remote LED annunciator, 3–32 VDC, supported by B210LP(A) and B501(A) bases only.
Specifications taken from the NOTIFIER data sheet “FST-851(A) Series Intelligent Thermal (Heat) Detectors with FlashScan,” document DN-6936:B (12/07/2011). Manufacturer specifications are subject to change without notice.
