Overview
The Haydon HAY-ACCESS12/24V8/4A-8W is a boxed access-control power supply with user-selectable 12 VDC or 24 VDC output. It delivers full continuous output (8 A at 12 V or 4 A at 24 V), provides battery-backup charging for standby batteries and includes an 8-way fused/fire‑interface board with independent switchable outputs and relay-trigger control.

• Selectable 12 VDC / 24 VDC operation (user selectable).
• Full rated continuous output: 8 A @ 12 V or 4 A @ 24 V.
• Battery back-up charger (supports common standby battery sizes noted by resellers).
• 8-way fused outputs with independent switching per output.
• Trigger relay (configurable NO/NC or +/– input) to control outputs.
• Mains, battery and fault LEDs; mains-fail/ancillary relay available.
• Enclosure sized to accept standby batteries and multiple access-control modules (typically holds up to six Paxton/ACT modules as standard).

Use cases
Designed for access control and security installations in commercial and institutional sites where a reliable, boxed PSU with battery backup and multiple fused outputs is required. Suitable for security installers and electrical contractors for powering locks, controllers, readers and ancillary devices.

Safety & compliance
Installation should be carried out by a qualified electrician or security engineer in accordance with local regulations and wiring standards. Refer to the official datasheet for precise battery wiring, cut‑outs, charger settings and any product certification marks (UKCA/CE): see the datasheet links in the specifications below.

Note
Some vendor listings report slight variations for battery charge current and nominal float voltages; consult the official Haydon datasheet for final installation and commissioning values.