Vesda Xtralis VPS-220-STX5 VESDA-E PSU STX 0.5A 14AH (Black) VESDA-E Power Supply Units are uniquely designed to complement the style and appearance of VESDA-E aspirating smoke detectors (ASDs) and are technically matched to provide sufficient current and battery charging capacity to meet the requirement of EN 54-4. The STX variants are VdS certified and CE marked to EN54-4 so are particularly suitable for use in territories where these approvals are required. These are the shallower units in the range with depth and width matching the VESDA-E detectors. Internally, they provide an EN 54-4 certified Power Supply rated to provide a 0.5A continuous 24Vdc supply whilst also charging the batteries (not supplied) which can be a 7, 12 or uniquely, 14Ah arrangement. As such the unit can be used with confidence to power, and provide 24hr standby (plus 0.5hr in alarm), for the VESDA VLF-500, VESDA-E VEP VESDA-E VES detectors and also the VESDA-E VEU detectors up to fan speed 5. The unit also provides a non-certified setting which enables it to power loads up to 1A while recharging batteries up to 12Ah in accordance with EN 54-4.