Aritech DP721I Conventional Optical Smoke Detector

1. Product Name: Aritech DP721I Conventional Optical Smoke Detector

2. Description:

What Is the Aritech DP721I Optical Smoke Detector?

The Aritech DP721I is a conventional optical smoke detector from the Dx700 series, designed for use in conventional fire alarm systems. It is zone-powered, has a remote indicator output and is CPR-certified. Its self-monitoring design and replaceable optical chamber provide a long-lasting, easy-to-maintain solution.

Operating Principle

The DP721I works using the light-scattering principle: smoke particles entering the optical chamber scatter light, and the detector senses this change and raises an alarm. Its sensitivity is 10%/m (+1.6%, -3.3%). The detector continuously monitors sensor sensitivity and operating status, automatically compensating each day for drift caused by background contamination to maintain factory calibration. Once a day, it performs a dynamic, full diagnostic test covering the detection chamber and internal electronics. If sensitivity falls outside the limits or the test fails, the condition is reported to the panel and the yellow fault LED on the detector lights up.

Role in Fire Detection Systems

In a conventional system, the DP721I detects smoke produced in the early stages of a fire and sends an alarm to the panel via the zone to which it is connected. During an alarm, the white LED turns red; the remote indicator output makes it possible to see the alarm from outside closed rooms or ceiling voids.

Why Choose It?

• Intelligent self-diagnostics: Daily full diagnostic testing and drift compensation help reduce the risk of false alarms.
• Separate fire and fault LEDs: Alarm and fault conditions can be clearly distinguished on site.
• Wide operating voltage range: The 8.5 to 33 VDC range makes it suitable for most conventional systems.
• Easy maintenance: The optical chamber can be removed and replaced on site; the detector calibrates itself automatically when powered up.
• Polarity-independent: Operates regardless of connection polarity, speeding up installation.

Installation and Commissioning

The detector is ceiling-mounted on an Aritech DB702 conventional base. The base is supplied with a short-circuit link between the IN and OUT terminals; this link opens when the detector is fitted, so cable continuity can be tested only through the bases. The device is polarity-independent, reducing the risk of wiring errors. If required, the locking tab on the base provides additional protection against unauthorised removal. For maintenance, hold a magnet at the detector's test point to start the sensitivity test; no external test equipment or test gas is required.

Technical Specifications

• Status indication: White LED (red during an alarm), yellow LED (test and fault)
• User interface: LEDs
• Reset voltage: <2.5 V (max.)
• Reset time: 1 s
• Number of alarm levels: 1
• Connection: Aritech conventional base
• Power supply type: Zone-powered
• Operating voltage: 8.5 to 33 VDC
• Current consumption: 100 µA (quiescent at 24 VDC) / <60 mA (alarm at 24 VDC)
• Detection principle: Optical light scattering
• Monitoring: Alarm threshold, contamination level
• Sensitivity: 10%/m (+1.6%, -3.3%)
• Zone length: Cable-dependent
• Number of outputs: 1
• Output type and rating: Remote indicator
• Programmable: No
• Remote alarm output: 30 mA
• Dimensions: 100 x 50 mm (Ø x H)
• Net weight: 112 g
• Colour: Cream white (RAL 9001)
• Mounting type: Ceiling-mounted
• Housing material: Plastic
• Vandal-resistant: No
• Operating temperature: -10 to 55°C
• Storage temperature: -10 to 70°C
• Application temperature (typical): +25°C
• Relative humidity: %0 to %95 (non-condensing)
• Environment: Indoor
• IP rating: IP43
• Compliance: CE, REACH, RoHS 3, WEEE
• Certification: CPR
• Standard: EN54-7

Applications

• Offices and administrative buildings
• Hotels and accommodation facilities
• Schools and educational institutions
• Shops and showrooms
• Hospital and clinic corridors
• Communal areas in residential projects

Compatible Products

The DP721I is used with the Aritech DB702 standard detector base. For a remote alarm indication, the AI672 conventional remote indicator or the buzzer-equipped AI673 can be used. The detector can be used in systems built with Aritech 1X-F4 and 1X-F8 conventional fire alarm control panels.

Frequently Asked Questions

Which base does the DP721I fit? It fits the standard conventional DB702 base in the Aritech Dx700 series.

How is the sensitivity test performed? Holding a magnet at the detector's test point starts the self-diagnostic routine; the LED indicates whether servicing is required.

Can the optical chamber be cleaned? Yes. The optical chamber can be removed for cleaning or replaced with a new, low-cost chamber.

At Narstek, we provide project support for the Aritech DP721I optical smoke detector and 700 series conventional products. Contact us for a quote and technical information.