Introduction to the Apollo XP95 Addressable Heat Detector (55000-400APO)
Apollo 55000-400APO — XP95 addressable fixed-temperature heat detector (A2S)is a loop-powered, addressable heat detector engineered for environments where smoke detection is impractical or prone to nuisance alarms. With a fixed alarm threshold of approximately 55°C (A2S) and an industry-standard XP95/Discovery protocol interface, the detector offers reliable thermal sensing using a single NTC thermistor and continuous sampling. The unit’s low-airflow polycarbonate housing, integrated red LED, remote indicator terminals and low quiescent current make it a strong choice for commercial and industrial applications such as kitchens, car parks, warehouses and plant rooms.
Key features at a glance
- Fixed-temperature classification:≈55°C (A2S) alarm point for rapid response to sustained heat rises.
- Addressable protocol:XP95 / Discovery loop-powered operation (17–28 V DC), enabling individual device identification and easier system fault finding.
- Reliable sensing:Single NTC thermistor with continuous sampling for steady thermal measurement.
- Construction:Low-airflow white polycarbonate housing (self-extinguishing) with stainless / nickel-plated terminals for durability.
- Visual indicators:Integral red alarm LED and remote indicator terminals (+R / −R) to support remote annunciation.
- Low power draw:Quiescent current optimised for addressable loops.
Detailed specifications and benefits
The Apollo XP95 55000-400APO packs technical design choices that prioritise reliability and compatibility with modern fire alarm systems. Below are the key specification highlights and what they mean in practical terms.
- Part number:55000-400APO.
- Classification:≈55°C (A2S fixed-temperature).
- Sensor:Single NTC thermistor — continuous sampling ensures stable temperature readings and predictable alarm behaviour.
- Protocol:XP95 / Discovery addressable — enables individual addressing and integration with compatible control panels.
- Supply voltage:17–28 V DC; protocol modulation 5–9 V peak-to-peak.
- Quiescent current:≈250–300 µA typical at 24 V; low standby drain is well-suited to long addressable loops.
- Alarm current (LED):≈2–4 mA when the LED is illuminated.
- Connections:L1 & L2 loop in/out; +R / −R remote LED terminals.
- Approvals:EN54-5 and other approvals (LPCB/CPR reported by manufacturer); confirm region-specific certificates from the datasheet.
- Dimensions:Ø100 × 42 mm (detector only); approximately 50 mm overall when on a base.
- Weight:≈105 g (detector only); ≈157 g with base.
- Operating temperature:−20°C to +70°C.
- Storage temperature:−30°C to +80°C.
- IP rating:Reported variably as IP43 / IP53 — check the datasheet and installation requirements for the exact protection level needed.
- Housing:Low-airflow white polycarbonate, self-extinguishing; terminals are stainless / nickel-plated for corrosion resistance.
- Reduced nuisance alarms:Heat detection avoids false alarms in dusty, oily or smoky-but-safe environments where optical smoke detectors would trigger unnecessarily.
- Addressable advantages:Individual addressing simplifies commissioning, diagnostics and targeted maintenance, reducing downtime and service costs.
- Robust installation:Low-airflow design and durable materials improve performance in high air-movement areas and harsh conditions.
- Visual and remote indication:The integral LED plus remote terminals make local and remote alarm indication straightforward for building management.
- Energy efficient:Low quiescent current enables longer loops and supports power budgeting on complex systems.
Use cases and scenarios where the detector excels
The Apollo XP95 55°C heat detector is purpose-built for areas where smoke detection is unsuitable or unreliable. Typical applications include:
- Commercial kitchens:Cooking fumes, steam and grease can cause frequent false alarms for smoke detectors. A fixed-temperature heat detector responds to persistent heat rises rather than transient particulates.
- Car parks:Vehicle emissions and dust make optical detectors prone to nuisance alarms. Heat detectors identify real thermal hazards such as engine fires.
- Industrial warehouses and production areas:Dust, lint and airborne contaminants in manufacturing sites reduce smoke detector effectiveness; heat detectors offer a reliable alternative.
- Plant rooms and boiler houses:Areas with high airflow near fans or ventilation where smoke sensors may underperform — a heat detector responds predictably to dangerous temperature increases.
- Dirty or oily environments:Locations with oil mist, soot or heavy dust that would coat smoke-sensing optics benefit from a fixed-temperature heat approach.
Comparisons with similar products and detection approaches
Choosing the right detector means balancing sensitivity, environment and system type. Below are practical comparisons to help specify correctly.
- Addressable units like the XP95 provide device-level identification, fault diagnostics and automatic polling—reducing maintenance time. Conventional heat detectors are simpler and cheaper but require zoned wiring and provide less diagnostic detail.
- A fixed-temperature detector alarms when ambient temperature reaches a set point (≈55°C). Rate-of-rise detectors trigger on rapid temperature increases, which can detect fast-developing fires sooner but are more susceptible to false alarms from sudden environmental changes (e.g., doors opening near heaters).
- Combination solutions (fixed + rate-of-rise) exist for faster detection in some scenarios; however, a 55°C fixed-temperature detector remains a reliable choice where sustained heat is the primary risk.
- Smoke detectors are typically more sensitive to early-stage smouldering fires and provide faster alerts in enclosed, clean-air spaces. Heat detectors are preferable in dirty, smoky or high-airflow environments where smoke sensors would nuisance alarm or be unreliable.
- Where both early warning and robustness are required, hybrid systems (smoke detectors in cleaner areas and heat detectors in harsh zones) provide comprehensive coverage.
Customer feedback and installer observations
While individual reviews vary by installation, common feedback from installers and facilities managers familiar with the Apollo XP95 heat detector includes the following representative comments:
- "Easy integration with existing XP95 panels and intuitive addressing — saved time during commissioning." — Installer, commercial projects.
- "Reliable in a busy kitchen environment where smoke detectors kept triggering. The 55°C threshold reduces nuisance alarms while still providing good protection." — Facilities manager, hospitality sector.
- "Low standby current and robust terminals make it suitable for long loops in a multi-storey car park system." — Fire systems technician.
These comments are representative of typical user experiences. For formal testimonials or case studies, consult installers or suppliers who have deployed the device in comparable environments.
Important installation notes and certification considerations
- Base compatibility:The detector mounts on a compatible XP95 base (sold separately) — ensure you specify the correct base for your installation.
- IP rating and environment:IP43 / IP53 is reported variably — confirm the required protection level from the manufacturer’s datasheet when deploying in exposed or washdown environments.
- Approvals:EN54-5 certification is listed; other approvals such as LPCB/CPR may apply depending on region. Check the datasheet for certificates required by your authority having jurisdiction.
- Competent installation:Installation and commissioning must be performed by a competent person in accordance with the manufacturer’s instructions and local fire regulations. Always isolate circuit power before wiring.
Conclusion — why choose the Apollo 55000-400APO XP95 Heat Detector?
The Apollo XP95 55°C (A2S) addressable heat detector is a purpose-built solution for demanding environments where smoke detection is impractical. Its addressable XP95/Discovery protocol support, low power consumption, clear visual indication and robust low-airflow housing make it an efficient, reliable choice for kitchens, car parks, warehouses, plant rooms and similar locations. With EN54-5 certification and proven installer preference for its integration and performance, the 55000-400APO offers an effective balance of reliability, maintainability and cost-efficiency.
Practical note:The detector is supplied without a base (base sold separately). Verify required IP protection and approvals for your region prior to specifying, and consult the Apollo datasheet and installation manual for full technical and compliance details.
