Description

The VESDA-E STX Power Supply Units are designed to visually and technically integrate with VESDA-E aspirating smoke detectors. Matching the detectors’ width, colour, and curved profile, these EN54-4 and VdS approved units feature an internal channel for detector exhaust, aiding back-venting installations. They are available in matt black or grey to complement various VESDA-E finishes.

Two versions cater to different power needs. The shallower VPS-220-STX provides a 0.5 Amp continuous 24VDC supply, charging up to 14 Ah batteries, and can power VESDA-E VEP detectors for over 24 hours or VEU detectors up to fan speed 6. The deeper VPS-250-STX delivers a 2 Amp continuous 24VDC supply for up to 24 Ah batteries, suitable for VEU detectors operating at higher fan speeds (up to 10).

Installation is simplified through cable entry knockouts that align with VESDA-E enclosures for direct mounting. Units provide external LEDs for ‘OK’ and ‘Fault’ conditions, alongside a change-over fault relay for integration with fire alarm systems. Internal links allow configuration adjustments for non-EN54-4 installations, such as disabling battery monitoring or altering charge current.

Key technical advantages include battery-alone operation for commissioning and full battery impedance checking. The units also safeguard batteries by disconnecting the load after prolonged mains failure (over 24 hours) and using a minimal current to monitor for mains restoration, preventing deep discharge.