Altronix T2SSK75F14D Dual-Voltage 14-Output Access Control Power Supply
Overview
The Altronix T2SSK75F14D is a UL294-listed power supply and battery backup enclosure engineered for mid-to-large commercial access control installations. Delivering simultaneous 24VDC at 10A and 12VDC at 10A from a single 120VAC/60Hz feed, it powers up to 14 individually PTC-protected door outputs — the right platform when a single-voltage, single-output box simply can't cover the panel count your project demands. For a broader look at the Altronix power distribution lineup, including smaller and single-voltage variants, the brand page is a useful starting point.
Key Features
- Dual 10A Output Rails (24VDC and 12VDC): Running both voltages at full 10A simultaneously means you can mix 24V electric strikes with 12V magnetic locks on the same chassis — no second enclosure, no extra conduit run. For large multi-reader deployments, that's real panel consolidation.
- 14 PTC-Protected Outputs at 2.5A Each: Each output is individually protected by a resettable PTC device rated at 2.5A. A shorted lock or faulty reader trips only its own output — the rest of the access control power supply keeps running. No fuse to pull, no service call to reset.
- Form C Relay Outputs (28VAC/VDC @ 2.5A): Onboard Form C relays let you integrate door position monitoring or alarm signaling directly at the power supply without external relay modules. Rated to 28VAC or VDC at 2.5A, they handle standard lock and alarm circuits cleanly.
- 1A Auxiliary Unswitched Output: A dedicated auxiliary rail at 1A stays live regardless of system state — useful for powering reader boards or credential readers that need continuous power independent of the door-output switching logic.
- 4 × 12VDC/12AH Battery Capacity: The enclosure accommodates four 12V/12AH batteries, providing meaningful standby runtime for multi-door sites where a power interruption must not compromise egress or security. Pair with verified sealed lead-acid batteries per your standby-hour calculation. See our access control category for compatible panels and readers that pair with this supply.
- UL294 and cUL (CAN/ULC-S319-05) Listed: Dual-listed for US and Canadian installations, the T2SSK75F14D satisfies the listing requirements most AHJs demand on access control projects without a separate approval process for cross-border work.
- Fused AC Input with Tiered Protection: A 5A/250V AC input fuse combined with 6.3A and 10A DC-side fuses provides layered overcurrent protection — protecting both the supply and downstream wiring from upstream fault conditions.
- 191 BTU/Hr Heat Dissipation: At full load the unit dissipates 191 BTU/Hr. Size your enclosure room or IDF accordingly — this isn't a concern in a ventilated electrical room, but it matters in a sealed closet.
- Operating Range 0°C to 49°C: Covers standard conditioned commercial environments. Not rated for unheated spaces below freezing — plan for a heated enclosure or interior location in cold climates.
- Large Enclosure Footprint (27.25″ × 21.5″ × 6.5″, 49 lb): Wall-mount planning is required. At 49 lb loaded with batteries, use proper lag anchors into studs or a dedicated backboard. Budget the wall real estate early — this is not a compact unit. Consult our power supply and accessories section for mounting hardware options.
Integration and Compatibility
The T2SSK75F14D is voltage-agnostic at the output — any 24VDC or 12VDC access control panel, lock, or reader drawing within the per-output 2.5A PTC limit is compatible. The dual-rail architecture supports mixed-voltage panels in a single enclosure. Form C relay contacts interface directly with standard alarm and door-monitoring inputs on most commercial panels. For installations using access control panels from major manufacturers, verify panel input current and verify battery sizing against your required standby duration before specifying.
Frequently Asked Questions
Q: Can the T2SSK75F14D supply both 24V and 12V simultaneously at full rated current?
A: Yes. Both the 24VDC and 12VDC rails are independently rated at 10A, so you can draw full current on both rails at the same time. They do not share a combined current pool.
Q: What battery type and size does the T2SSK75F14D support?
A: The enclosure is designed for four 12VDC/12AH sealed lead-acid batteries. Actual standby runtime depends on your total load current — calculate runtime based on your specific door and reader draw.
Q: Is the T2SSK75F14D UL listed for access control applications?
A: Yes. It carries UL294 listing and cUL listing to CAN/ULC-S319-05, covering both US and Canadian jurisdictions.
Q: How many individually protected outputs does the T2SSK75F14D provide?
A: Fourteen outputs, each PTC-protected at 2.5A. A fault on one output trips only that circuit — the remaining 13 continue operating normally.
Q: What is the maximum heat output of this unit at full load?
A: At full load, the T2SSK75F14D dissipates 191 BTU/Hr. Plan for adequate ventilation in the installation space, especially in confined electrical closets.
Q: Can the Form C relays be used for door position or alarm signaling?
A: Yes. The Form C relay contacts are rated to 28VAC or VDC at 2.5A, suitable for integrating door position monitoring or alarm signaling inputs on standard commercial access control panels.
When I spec a multi-door commercial access control project and the panel mix includes both 24V strikes and 12V mag-locks, the T2SSK75F14D is the unit I reach for — the independent dual-rail architecture (24VDC and 12VDC, each at a full 10A) eliminates the second enclosure that single-voltage supplies force on you. That's a real reduction in wall space, conduit, and commissioning time on a 14-door deployment.
Technical Highlights:
- Dual 10A Independent Rails: 24VDC and 12VDC each rated at 10A — not shared. Mixed-voltage lock and reader inventories run from one enclosure without derating either rail.
- 14 PTC Outputs at 2.5A Each: Resettable protection means a shorted output self-isolates and resets without a service call. On a 14-door system, that's the difference between a nuisance trip and a facility-wide access event.
- Four-Battery Bay (4 × 12V/12AH): Substantial standby capacity at this enclosure size. Size your runtime target against actual door load — a lightly loaded system at 4 × 12AH will run considerably longer than a fully loaded one.
Deployment Considerations:
- At 49 lb with batteries installed, wall mounting requires lag anchors into structural studs or a dedicated plywood backboard — a drywall anchor installation is not adequate for this weight class.
- The 191 BTU/Hr full-load heat output is manageable in a ventilated electrical room but can cause thermal issues in a sealed closet; verify that your enclosure space has at least passive airflow before sign-off.
The T2SSK75F14D is the right call for mid-size commercial buildings — corporate offices, healthcare facilities, or education campuses — where 14 doors need mixed-voltage power and battery backup from a single, listed enclosure. If your project is under 8 doors or single-voltage only, a smaller Altronix variant will save wall space and cost.
