Altronix AL125ULP Power Supply/Charger

The Altronix AL125ULP is a UL 294-listed access control power supply/charger designed to power electric locks, magnetic locks, and compatible security equipment. Converting 24VAC from an included 40VA plug-in transformer into selectable 12VDC or 24VDC power, it provides two individually PTC-protected Class 2 outputs with a combined capacity of 1A at 12VDC or 0.5A at 24VDC. The unit features fail-safe/fail-secure lock control, supervised fire alarm disconnect, a built-in battery charger, and a locking metal enclosure for indoor installations.

Altronix AL125ULP 12/24VDC Access Control Power Supply/Charger with Transformer

The Altronix AL125ULP Access Control Power Supply/Charger provides regulated DC power and electronic locking control for commercial access control, intrusion security, and fire alarm interface applications. Designed for systems requiring 12VDC or 24VDC power, the AL125ULP converts a 24VAC, 40VA input from its included plug-in transformer into two individually protected Class 2 power-limited outputs. The power supply delivers a combined maximum current of 1A at 12VDC or 0.5A at 24VDC, supporting compatible electric strikes, electromagnetic locks, access control devices, and auxiliary security equipment. Its output configuration includes a switched locking device output and an unswitched auxiliary power output, allowing one power supply to support controlled door hardware and equipment requiring continuous power. The integrated access control trigger input accepts normally open control signals from compatible card readers, request-to-exit devices, or access control systems, while its supervised fire alarm disconnect interface supports door-release requirements during designated emergency conditions.

The AL125ULP switching power supply features filtered, electronically regulated 12VDC or 24VDC output, selectable through an onboard voltage configuration switch. Both Class 2 outputs incorporate auto-resetting PTC protection rated at 2.5A, providing protection against short circuits, thermal overloads, and excessive electrical current. The PTC protection rating is separate from the power supply's maximum continuous output capacity. The switched output includes dedicated LOCK+, STRIKE+, and COM- terminals for operating fail-safe and fail-secure locking devices, while the AUX terminals provide uninterrupted output independent of access control triggers or fire alarm activation. The unit includes a supervised fire alarm control panel interface that supports latching operation with manual reset or non-latching operation, configured through an onboard switch. A 2.2k-ohm end-of-line resistor supervises the fire alarm interface circuit, while an integrated status LED displays normal operation, loss of AC power, output failure, or an activated trigger condition. The AL125ULP is UL 294 listed for Access Control System Units and cUL listed to CSA C22.2 No. 205-M1983 for signal equipment.

The Altronix AL125ULP incorporates a built-in sealed lead-acid or gel battery charger with a maximum charging current of 400mA and automatic transfer to standby battery power when AC input is lost. The power supply supports a 12VDC backup battery for 12V operation or two 12VDC batteries connected in series for 24V operation, providing backup power according to the connected equipment's current requirements and installed battery capacity. The unit is supplied with a 24VAC/40VA plug-in transformer, battery leads, mounting hardware, and a wall-mount metal enclosure with cam lock; standby batteries are sold separately. The indoor enclosure measures approximately 8.125 inches high, 7.4 inches wide, and 3.55 inches deep (206.4 x 188 x 90.2 mm) and accommodates up to two 12VDC/4Ah batteries. Combination knockouts support 1/2-inch and 3/4-inch conduit connections, simplifying field wiring and cable routing. The power supply operates at temperatures from 32 F to 120 F (0 C to 49 C) and supports a specified relative humidity of 85% 5%.

Designed for commercial offices, retail facilities, institutional buildings, and electronically controlled entrances, the AL125ULP provides a centralized power solution for access control systems requiring reliable DC output, supervised fire alarm integration, and optional battery backup. Its fail-safe and fail-secure locking outputs support different electric locking configurations, while the normally open trigger input enables controlled operation through compatible security controllers, push buttons, and request-to-exit devices. The fire alarm interface automatically changes the switched lock output state when an alarm or supervised circuit fault condition occurs, allowing appropriately configured door hardware to respond according to the facility's life safety design. Installation requires connecting the included transformer to the XFMR input terminals, selecting the appropriate output voltage, wiring the locking and auxiliary devices, and configuring the fire alarm and trigger inputs according to the manufacturer's instructions. The AL125ULP is backed by an Altronix lifetime warranty and is intended for installation according to the AL125UL Series Installation Guide, applicable electrical codes, and fire alarm interface requirements. Unlike the AL125UL, which uses an internal 115VAC transformer, the AL125ULP includes an external 24VAC plug-in transformer for low-voltage power connections.