Optex QXI‑DT‑X8 Dual‑Tech Outdoor Motion Detector, 12m/120°, 9.5–16V

Introduction: Optex QXI‑DT‑X8 at a glance

The Optex QXI‑DT‑X8 Dual‑Tech Outdoor Motion Detector is a hard‑wired perimeter sensor designed to deliver reliable detection and high false‑alarm immunity in outdoor environments. Combining a quad‑element passive infrared (PIR) sensor with a microwave (Doppler) sensor, the QXI‑DT‑X8 offers a 12 m × 120° coverage pattern, selectable mounting modes for different installation scenarios, and weatherproof construction rated to IP54. With digital processing (SMDA), double conductive shielding and an anti‑masking/anti‑blocking behaviour in multi‑level mode, this detector is aimed at installers and users who need stable detection near gates, driveways, building approaches and property perimeters.

Key features

• Dual‑technology sensing: Quad‑element PIR combined with a microwave Doppler sensor for improved stability and reduced false alarms.
• Wide coverage: 12 m × 120° detection area suitable for perimeter and approach detection typically needed at entrances, driveways and garden boundaries.
• Selectable mounting modes: Multi‑level mode (2.2–2.7 m) for typical perimeter applications and pet‑alley mode (0.8–1.2 m) for narrow corridors where pets may be present.
• Anti‑masking/anti‑blocking: DT model includes anti‑masking behaviour when installed in multi‑level mode to detect deliberate tampering or obstruction.
• SMDA and shielding: Super Multi‑Dimensional Analysis (digital processing) and double conductive shielding reduce interference from environmental noise, RF and visible light.
• Weatherproof housing: UV‑resistant ASA material and IP54 ingress protection for durable outdoor performance.

Detailed specifications and benefits

The QXI‑DT‑X8 uses a quad‑element PIR array paired with a microwave Doppler sensor. The PIR is sensitive to thermal contrast from moving targets, while the microwave element actively senses motion using Doppler shift. By requiring confirmation from both technologies (dual‑tech operation), the detector significantly reduces the likelihood of false alarms triggered by environmental factors such as sunlight, swaying vegetation or sudden temperature changes. SMDA (Super Multi‑Dimensional Analysis) further refines signal processing to distinguish genuine intrusions from spurious events.

The standard coverage is 12.0 m with a 120° field of view — roughly 40 ft by 120°. The detector is optimized to detect target speeds between 0.3 and 2.0 m/s, which covers walking pace and running movements commonly seen in perimeter intrusions or approach detections. Manufacturer reference sensitivity is typically listed as 2.0 °C at 0.6 m/s.

The unit is hard‑wired for 9.5–16 V DC supply voltage and draws a maximum of approximately 30 mA at 12 V DC. Alarm outputs are selectable as normally closed (N.C.) or normally open (N.O.) and are rated to 28 V DC at 0.1 A (max). A separate trouble/tamper output is provided (N.C., 28 V DC, 0.1 A max) and will open if the cover is removed. Alarm pulse duration is around 2.0 ± 0.5 s and the detector has a warm‑up period of roughly 60 seconds during which the internal LED indicates status.

Installers can select between multi‑level mounting (recommended 2.2–2.7 m) for general perimeter coverage and pet‑alley mounting (0.8–1.2 m) for narrow zones where small animals may be present. When set to multi‑level mode, the DT variant incorporates anti‑blocking/anti‑masking behaviour. This is important for applications where an intruder might place an object over the sensor to defeat detection — the detector will recognise abnormal conditions and trigger a tamper/alarm output where supported by the control panel wiring.

The housing is manufactured from UV‑resistant ASA plastic and the unit carries an IP54 ingress protection rating, offering protection against dust ingress and water spray. The operating temperature range of −40 °C to +45 °C and tolerance to up to 95% relative humidity make it suitable for a wide range of climates. Additionally, double conductive shielding reduces false responses caused by strong visible light or radio frequency interference, improving reliability in challenging outdoor environments.

Use cases and scenarios where the QXI‑DT‑X8 excels

• Perimeter and approach detection for homes and small commercial sites: The wide 120° field of view and 12 m range make the detector a good fit for driveways, front approaches and garden perimeters where early detection is desirable.
• Integration with alarm panels and CCTV: Hard‑wired alarm outputs and tamper monitoring allow the QXI‑DT‑X8 to trigger alarm systems or video verification cameras to capture events for evidence or monitoring centres.
• Environments with potential interference: SMDA processing, double shielding and microwave/PIR fusion reduce nuisance activations in areas with reflective surfaces, vehicle headlights, heavy foliage or electromagnetic noise.
• Sites requiring anti‑masking: Multi‑level installations where tamper or deliberate masking is a concern — such as commercial premises, equipment compounds or gated properties — benefit from the DT anti‑masking capability.
• Installations with pets: When mounted in pet‑alley mode, the detector is able to ignore small animals moving close to the ground while still detecting human intruders moving through the protected lane.

Comparisons with similar products and technologies

When evaluating outdoor motion detectors, buyers typically compare single‑technology PIR sensors, microwave‑only sensors, and dual‑technology (DT) units like the QXI‑DT‑X8. Understanding the trade‑offs helps choose the right device for the site.

Single‑technology PIR detectors are simple and cost‑effective but can be more prone to false alarms caused by ambient temperature shifts, sunlight and moving vegetation. Dual‑tech detectors reduce these false alarms by requiring concordant signals from both PIR and microwave sensors. The QXI‑DT‑X8 therefore offers greater reliability in busy outdoor environments where nuisance alarms are a concern.

Microwave‑only sensors can detect motion through some obstructions and are less affected by temperature, but they are more susceptible to cross‑talk and reflections from moving metallic objects or traffic. Combining microwave with PIR leverages the strengths of both and removes many single‑technology weaknesses. The QXI‑DT‑X8’s SMDA processing further helps to filter spurious microwave echoes.

Wired detectors like the QXI‑DT‑X8 require a wired connection to the alarm panel, which provides consistent power and generally more reliable signalling than battery‑powered wireless options. For permanent installations where power runs are practical, a hard‑wired DT sensor offers stable performance and no battery maintenance. Wireless alternatives add installation flexibility but may need periodic battery changes and can be affected by signal range and RF congestion.

The Optex QXI‑DT‑X8 sits in the pragmatic middle ground for installers and property owners who want proven dual‑tech detection with practical outdoor durability. It offers more advanced processing and anti‑masking than basic outdoor PIRs while avoiding the complexity and cost of high‑end perimeter beam solutions or integrated multisensor camera systems. For many residential and small commercial projects, it balances price and performance effectively.

Customer feedback and installer observations

While individual reviews vary by site conditions and installation quality, typical feedback from installers and end users highlights the following points:

• Reliability— Installers commonly report fewer nuisance alarms compared to single‑tech outdoor PIRs once the detector is correctly mounted and the sensitivity adjusted to the site.
• Ease of installation— Hard‑wired connections with selectable output modes and clear mounting height options make the QXI‑DT‑X8 straightforward to install for experienced technicians.
• Robust outdoor performance— Users value the IP54 housing and UV‑resistant construction for exposed locations; the detector tolerates a wide temperature range without performance loss.
• Anti‑masking reassurance— For higher‑risk sites, the anti‑masking capability in multi‑level mode provides extra peace of mind against tampering attempts.

Note: explicit manufacturer warranty information is not specified here; purchasers should confirm warranty and approvals (CE/UKCA or regional certifications) with the supplier or consult the official Optex datasheet.

Conclusion: why choose the QXI‑DT‑X8?

The Optex QXI‑DT‑X8 Dual‑Tech Outdoor Motion Detector is a capable, no‑nonsense choice for installers and property owners who need dependable outdoor detection with strong false‑alarm immunity. Its dual‑technology sensor fusion, SMDA processing and double shielding reduce nuisance triggers, while selectable mounting modes and anti‑masking behaviour make it adaptable to a range of perimeter and approach scenarios. Weatherproof construction and sensible electrical interfaces support reliable integration with conventional alarm panels and CCTV verification systems. For projects where a wired, rugged DT sensor is required, the QXI‑DT‑X8 presents a balanced option in terms of performance and cost — the suggested retail price is around A3114.99 (check local pricing and supply), and installers should consult Optex datasheets for full wiring and compliance details before specification.