Introduction to the Haydon EN54-4 27.6V DC 2A Fire Alarm Power Supply
The Haydon HAY-PSUEN54-2A (marketed as the Haydon 27.6V EN54-4 PSU 2A) is a compact, standards-compliant uninterruptible power supply (UPS) designed specifically for fire detection and alarm systems. Built to the EN54-4 standard, this unit delivers a regulated 27.6 V DC output at a rated continuous current of 2 A and includes an integrated battery charger, internal battery compartment for standby cells, fault signalling, and a lockable tamper-protected steel enclosure. Its combination of compliance, essential safety features, and straightforward installation makes it a strong choice for contractors, system integrators and building managers seeking a reliable power source for small to medium fire alarm installations.
Key features at a glance
- EN54-4 compliant— meets the European standard for fire alarm power supplies.
- 27.6 V DC, 2 A output— continuous uninterruptible power for detectors, callpoints and sounders.
- Integrated battery support— supports typical internal batteries (2 × 7 Ah SLA) with charger and deep-discharge protection.
- Wide mains input range— accepts approx. 110–240 VAC, 47–63 Hz for flexible installation.
- Fault and monitoring— mains/battery/fault LEDs plus a volt-free mains-fail relay for remote signalling.
- Secure enclosure— lockable, tamper-detecting steel enclosure with hinged lid.
Detailed specifications and benefits
The HAY-PSUEN54-2A packs a focused set of electrical and mechanical features tailored to fire alarm systems. Understanding these specifications helps explain the practical benefits you get on-site.
- Output voltage:27.6 V DC — a common nominal voltage for conventional fire system peripherals, ensuring compatibility with many detectors, sounders and control modules.
- Rated output current:2 A continuous — ideal for small-to-medium systems or as localised power for a zone of devices.
- Mains input:approx. 110–240 VAC, 47–63 Hz — wide input range simplifies procurement and supports installations across different regions and wiring supplies.
- Battery charger:Typical charger current ≈0.5 A — sized to maintain standby SLAs while managing charge cycles to extend battery life.
- Output ripple:<100 mV (typical) — low ripple helps prevent nuisance activations and maintains stable operation of sensitive electronics.
- Fusing:Output and battery fuses fitted — ensure correct protection and isolate faults quickly (refer to datasheet for exact ratings).
- Supported battery:Typical internal fitment of 2 × 7 Ah sealed lead–acid (SLA) batteries — provides required standby autonomy for many applications.
- Protection features:deep-discharge cut-off, low-voltage & short-circuit detection, and temperature monitoring — all contribute to battery longevity and system safety.
- Internal compartment:batteries housed inside a lockable steel enclosure for security and neat installation.
- Fault relay:volt-free mains-fail / fault relay output for remote monitoring and integration with building management or alarm panels.
- LED indicators:dedicated mains, battery and fault LEDs provide clear local status at a glance.
- Tamper detection:lid-open tamper switch and lockable hinged steel enclosure to deter unauthorised access and protect against tampering.
- Physical:compact enclosure (typical dimensions approx. 275 × 330 × 80 mm) suitable for wall mounting in service cupboards, plant rooms or distribution areas.
Use cases and scenarios where the product excels
The Haydon 27.6V EN54-4 2A PSU is designed for practical real-world deployments. Typical applications include:
For retail outlets, small offices, restaurants and similar premises, the 2 A output is often sufficient to power a single fire alarm panel plus connected sounders and detectors across one or more zones. The compact, lockable enclosure allows tidy wall mount installations in riser cupboards or plant rooms.
Shared-residence buildings, student accommodation and small apartment blocks can use this unit to provide EN54-4 compliant backed power for communal detection zones or localised sub-systems where larger central PSUs are unnecessary.
When upgrading older systems to achieve compliance with EN54-4 or when adding battery-backed power in retrofit scenarios, this PSU provides a straightforward replacement or addition. The wide mains input and compact footprint make it simple to swap into existing installations.
The volt-free fault relay and clear LED indicators make this PSU suitable where remote fault reporting to a fire panel or building management system is required. Tamper detection also supports enhanced site security and compliance with audit/regulatory checks.
Comparisons with similar products on the market
When selecting a power supply for a fire alarm system, installers typically weigh capacity, compliance, form factor and monitoring features. Here is how the Haydon HAY-PSUEN54-2A compares against common alternatives:
- Higher-capacity EN54-4 PSUs (3A, 5A and above):Larger units deliver greater continuous current for bigger panels and more devices. If your system needs sustained high-current operation or supports many sounders/detectors, choose a higher-rated PSU. The Haydon 2A unit, however, fits smaller installations where excess capacity would be wasted.
- PSUs with remote telemetry or supervised outputs:Some competitors offer integrated remote monitoring via serial, network or supervised signalling channels. If centralised cloud or network-based fault reporting is a priority, consider units with expanded telemetry. The HAY-PSUEN54-2A focuses on essential volt-free relay signalling and local status LEDs — the simpler approach preferred by many installers for reliability and cost.
- Modular or redundant power systems:For mission-critical sites (data centres, hospitals), modular redundant power designs give failover beyond single-battery protection. The Haydon 2A PSU is aimed at conventional fire detection systems rather than fully redundant power architectures.
- Value and compliance:Against comparable 2 A EN54-4 PSUs, Haydon’s unit competes strongly on price-to-feature balance: it combines required EN54-4 compliance, a tamper-proof enclosure and battery management in a compact package that is often more cost-effective than heavily featured models.
Conclusion: Why the Haydon HAY-PSUEN54-2A is a solid choice
The Haydon EN54-4 27.6 V DC 2 A power supply offers a balanced mix of compliance, core safety features and practical installation benefits. It suits many small-to-medium fire alarm applications where EN54-4 certification is required and where a compact, tamper-protected enclosure is beneficial. Key advantages include EN54-4 compliance, internal battery support with protection features, a wide mains input range for flexible deployment, and fault signalling for integration with broader building systems.
While larger or more feature-rich PSUs may be necessary for bigger or mission-critical sites, the HAY-PSUEN54-2A provides a dependable, cost-effective option for contractors and facilities managers who need an industry-standard, uncomplicated solution. For full installation guidance, electrical tables, fuse ratings and wiring diagrams, always consult the manufacturer's datasheet and ensure installation is performed by a competent person in accordance with local regulations such as BS 5839.
With its clear focus on regulatory compliance and practical site needs, the Haydon 27.6V EN54-4 2A PSU is a sensible choice where dependable, battery-backed fire alarm power is required.
