Altronix T1MK1FPA4D 24VDC Power Supply with Integrated Access Controller Output
Overview
The Altronix T1MK1FPA4D is a 120VAC-input, 24VDC power supply and access controller output unit housed in a spacious 18" x 14.5" x 4.625" enclosure — the kind of all-in-one power platform that integrators reach for when they need a single panel to handle both door-strike/lock power and access controller logic without mounting separate supplies. Rated at 3.6A maximum supply current with a nominal DC output range of 20.28–26.4V, the T1MK1FPA4D fits cleanly into commercial access control deployments where you need reliable, code-compliant power distribution behind the panel door. The EFLOW architecture manages load distribution while PTC (Positive Temperature Coefficient) resettable overcurrent protection eliminates the nuisance of manually replacing blown fuses on field-side outputs.
Drawing 3.5A from a 120VAC 60Hz line and protected upstream by a 5A/250V input fuse, this unit is sized for typical commercial branch circuits — no dedicated circuit upgrade required in most installations. The integrated battery circuit, fused at 7.5A/32V, supports a standby battery for continuity during power outages, a non-negotiable requirement in access control and surveillance infrastructure where a loss of power can mean an unsecured door or a gap in the recorded timeline.
Key Features
- 3.6A Maximum Supply Current at 24VDC: The 20.28–26.4V nominal output range covers standard 24VDC access control hardware — electric strikes, maglocks, and readers — without pushing out of spec. At 3.6A, there's headroom to power multiple door-side devices on a single supply without thermal throttling.
- Dedicated 2.0A Access Controller Output: A separate, independently fused 2.0A output for the access controller board keeps controller logic power isolated from door-hardware power. Voltage sags on a lock release won't drag down the controller bus — a common cause of spurious access events in less carefully designed installations.
- PTC Resettable Overcurrent Protection on Distribution: The 2.5A PTC fuse on power distribution outputs resets automatically after a fault clears. On a multi-door panel with several output runs, this matters: a short on one run won't take the others down permanently, and a service call to swap a fuse is avoided.
- 7.5A/32V Battery Fuse: The dedicated battery circuit, fused at 7.5A/32V, allows connection of a sealed lead-acid standby battery. When line power drops, the system transitions to battery without interruption — keeping doors secured and recorders running through brief outages.
- 5A/250V Input Fuse + 9A Access Controller Input Fuse: Dual upstream protection — 5A on the AC input and 9A on the access controller input path — provides layered fault isolation. A wiring error or surge on the controller side doesn't propagate back into the power supply or upstream panel.
- 18" x 14.5" x 4.625" Enclosure: The large enclosure provides real working room. Integrators can land and dress cabling cleanly, mount a battery inside (depending on AH rating and battery dimensions), and still have space for auxiliary terminal blocks. Tight enclosures that require you to fight cabling every time you open the panel are a maintenance problem — this one isn't.
- EFLOW Architecture: Altronix's EFLOW design manages current flow to optimize efficiency and thermal performance across the output channels. In practice, this translates to lower heat buildup during sustained load — relevant in equipment rooms where thermal management is already a concern.
Integration and Compatibility
The T1MK1FPA4D is designed for commercial access control environments operating on 24VDC infrastructure. The 20.28–26.4V output envelope is compatible with the majority of commercial electric strikes, electromagnetic locks, and access control panels that specify 24VDC input. The dedicated 2.0A access controller output is sized for single-door or two-door controller boards from major access control manufacturers — verify your controller's rated current draw against the 2.0A output before specifying.
The 7.5A/32V battery fuse supports 12V sealed lead-acid batteries wired in series for 24V standby — a standard configuration in access control. Battery capacity selection depends on load profile and required backup duration; this unit provides the circuit, not the battery. If you are sourcing a complete access control solution, pair this supply with a compatible controller and reader hardware from the Altronix product line.
For installations requiring PoE-powered IP cameras alongside access control, consider a separate PoE switch for camera power rather than attempting to derive PoE from this supply — the T1MK1FPA4D is a 24VDC access control power platform, not a PoE source. For guidance on sizing power infrastructure across a mixed access-control and surveillance deployment, review a power supply selection guide before finalizing your bill of materials.
Mount the enclosure in a secured, conditioned space. The 18" x 14.5" panel size requires a wall section or rack enclosure with adequate depth (4.625") and clear vertical space. Surface-mount or recessed installation depends on your AHJ and facility requirements.
Frequently Asked Questions
Q: What is the maximum output current of the T1MK1FPA4D power supply?
A: The T1MK1FPA4D delivers a maximum supply current of 3.6A at a nominal DC output voltage of 20.28–26.4V (24VDC). The dedicated access controller output is rated at 2.0A separately.
Q: Does the T1MK1FPA4D support a standby battery for backup power?
A: Yes. The unit includes a dedicated battery circuit fused at 7.5A/32V, which supports connection of a sealed lead-acid standby battery for continuity during power outages. The battery itself is not included.
Q: What input power does the T1MK1FPA4D require?
A: The unit operates on 120VAC, 60Hz at 3.5A input current. It is protected on the AC input side by a 5A/250V fuse. A standard 15A or 20A commercial branch circuit is sufficient.
Q: What does PTC protection mean on the T1MK1FPA4D, and why does it matter?
A: PTC stands for Positive Temperature Coefficient — a resettable overcurrent protection device. Unlike a one-time fuse, a PTC automatically resets after the fault condition clears. On a multi-door access control installation, this prevents a single wiring fault from permanently disabling an output run, reducing service calls.
Q: What are the enclosure dimensions for the T1MK1FPA4D?
A: The enclosure measures 18" wide x 14.5" tall x 4.625" deep. This provides substantial interior working space for cable dressing, terminal connections, and optional battery installation.
Q: Is the T1MK1FPA4D suitable for powering IP cameras directly?
A: No. The T1MK1FPA4D is a 24VDC access control power supply — it is not a PoE source and is not designed to power PoE IP cameras. For IP camera power, use a dedicated PoE switch or PoE injector matched to your camera's power class.
The thing I keep coming back to on the T1MK1FPA4D is the isolated 2.0A access controller output — that separation from the door-hardware power rail is exactly what prevents the most common source of phantom access events I've seen in the field: a maglock release pulling the supply rail down momentarily and confusing the controller. Altronix built that isolation in by design rather than leaving it to the integrator to sort out with inline regulation.
Technical Highlights:
- 2.0A Isolated Controller Output: Protected by its own 2.5A output fuse and a 9A input fuse on the controller feed path — the controller logic power is fully segregated from the 3.6A door-hardware supply bus, eliminating cross-load interference.
- PTC Resettable Distribution Fusing: The 2.5A PTC on distribution outputs resets automatically after a fault clears — no field swap required. On a multi-run panel, one shorted output doesn't cascade into a service call on every door in the wing.
- 7.5A/32V Battery Circuit: Supports 24V standby via series-wired 12V SLA batteries. The 7.5A fuse rating gives adequate headroom for battery charge current while protecting the supply from a shorted battery cell — a real failure mode on aged SLA cells in unconditioned spaces.
Deployment Considerations:
- The 18" x 14.5" x 4.625" enclosure gives genuine working room — you can land conduit, dress cabling, and still seat a mid-capacity SLA battery inside without it being a fight. Measure depth clearance on your wall section before ordering; 4.625" is deeper than typical low-profile panels.
- Input draw is 3.5A at 120VAC — confirm your branch circuit has clean, dedicated power before installation. Sharing a circuit with HVAC or lighting loads is the fastest way to introduce noise artifacts and nuisance resets on sensitive access controller logic boards.
The T1MK1FPA4D is a solid specification for commercial single-tenant office or light industrial deployments where the AHJ requires battery backup, the door count is moderate (two to four doors on a single supply), and the panel needs to live in a finished telecom closet where cable management actually matters.
