Overview
The HAY-PSUEN54-2A is an EN54-4 compliant 27.6 V DC uninterruptible power supply with integrated battery backup for fire detection and alarm systems. It provides automatic switchover to battery on mains loss and includes battery monitoring, deep-discharge protection and electronic overload protection. Supplied in a lockable, tamper-protected steel enclosure.

• EN54-4 compliant 27.6 V DC uninterruptible output
• Rated continuous output current: 2 A
• Wide mains input: approx. 110–240 VAC, 47–63 Hz
• Integrated battery charger and support for internal standby batteries (typical: 2 × 7 Ah SLA on 2 A model)
• Mains / battery / fault LEDs and a volt-free mains-fail relay for remote fault signalling
• Tamper/lid-open detection and lockable hinged steel enclosure

Use cases
Designed for use with fire detection and alarm systems where EN54-4 compliance is required. Suitable for both contractor installation and system upgrades in commercial and residential buildings.

Compliance & safety
EN54-4 compliant — refer to the official datasheet for full certification, CE/UKCA markings and detailed test information. Installation must be performed by a competent person in accordance with manufacturer instructions and relevant UK standards (eg. BS 5839). Always isolate mains before installation and follow the supplied wiring diagrams.

For full electrical tables, fuse ratings, exact enclosure dimensions and wiring diagrams, consult the product datasheet / installation manual supplied by the manufacturer.