Altronix MAXFIT77L 8-Output 24VDC Power Supply with Dual Access Control Modules
Overview
The Altronix MAXFIT77L is a high-capacity, multi-output power distribution unit engineered for commercial access control and video surveillance installations where a single, UL-listed power chassis needs to drive multiple field devices simultaneously. Combining dual ACM8 access control modules with a BC750 battery enclosure inside a single 6.25 x 15.50 x 20.50 in cabinet, the MAXFIT77L delivers up to 10A of 24VDC output across 8 individually managed outputs — enough to power a full rack of card readers, locks, and auxiliary surveillance devices without external power consolidation.
This unit is built around Altronix's MaxFit platform, which focuses on pre-integrated, UL-listed assemblies that reduce field wiring time and eliminate the compatibility guesswork associated with mixing discrete power and access control hardware. If you're sizing power infrastructure for a mid-to-large door deployment, the MAXFIT77L fits the access control power segment of the access control category where pre-certified, multi-output solutions reduce both commissioning risk and inspection friction.
Key Features
- Dual ACM8 Modules Integrated: Two ACM8 access control modules ship pre-installed in the chassis, providing 8 individually supervised outputs per module. This consolidates what would otherwise require two separate enclosures and external wiring harnesses — a direct reduction in labor hours during installation.
- 10A @ 24VDC Total Output: A 10-amp aggregate output at 24VDC supports the simultaneous operation of multiple electric locks, magnetic locks, and auxiliary devices without oversubscribing a single supply. Budget roughly 500mA to 1A per electric strike; this unit can comfortably power 8–12 devices depending on load profile.
- Wide Input Voltage Range (12–24V AC or DC): Accepting 12 to 24V AC or DC input gives installers flexibility when interfacing with building transformer infrastructure that may not be uniform across a campus — no step-down transformer required in most commercial installations.
- BC750 Battery Enclosure Included: The integrated BC750 enclosure provides space for standby battery backup — critical for access control installations where power loss must not cause uncontrolled door-unlock events. The cabinet handles the battery integration without requiring a separate external box.
- UL Listed Assembly: UL listing on the complete assembly — not just the individual components — simplifies AHJ approval. Having a UL-listed multi-output power supply matters during fire marshal or building inspection sign-off, particularly in jurisdictions that require listed equipment at every stage of the power distribution chain.
- Compact Footprint for the Capacity: At 25.75 lbs and 20.50 in tall, the MAXFIT77L packs dual ACM8 modules plus battery enclosure into a cabinet sized for IDF closets and telecom rooms. Compare this to the footprint required to mount two separate ACM8 enclosures plus a standalone power supply and battery box — the space savings are real on dense deployments.
- 8-Output Architecture: Eight discrete outputs allow per-door circuit isolation. If a short or overload condition occurs on one output, the remaining seven outputs remain operational — an important behavioral guarantee in multi-door deployments where partial failure must not cascade.
Integration and Compatibility
The MAXFIT77L is designed for integration into commercial access control power supply architectures alongside Altronix's broader access control ecosystem. The dual ACM8 modules interface with standard access control panels that manage relay outputs — the ACM8 handles power distribution and supervision while the panel handles credential logic. Review your panel's relay output voltage and current specs against the MAXFIT77L's 24VDC output before wiring; most commercial panels (including those from major manufacturers) are compatible with 24VDC auxiliary power inputs, but verify relay coil ratings for your specific lock hardware. For broader context on sizing power infrastructure in multi-door deployments, consult an access control buying guide before finalizing your load calculations. When pairing with Altronix products, this unit fits naturally into the Altronix product line as a MaxFit platform assembly. For installations that also involve IP video, note that the MAXFIT77L does not provide PoE outputs — camera power should be handled by a dedicated PoE switch or camera-specific power supply rather than drawing from this access control unit's outputs.
Frequently Asked Questions
Q: What is the total output current of the MAXFIT77L?
A: The MAXFIT77L delivers a total of 10A at 24VDC across its 8 outputs. Budget your connected device loads accordingly — electric strikes, magnetic locks, and auxiliary devices must not exceed this aggregate without risking output voltage sag.
Q: What input voltage does the MAXFIT77L accept?
A: The unit accepts 12 to 24V AC or DC input, giving installers flexibility to interface with a range of building transformer configurations without an additional step-down stage.
Q: Does the MAXFIT77L include battery backup capability?
A: Yes. The integrated BC750 battery enclosure is included within the cabinet to house standby batteries, supporting code-compliant backup power for access control locks. Battery cells are not included — size the battery bank to your required holdover time and total load.
Q: How many access control outputs does the MAXFIT77L provide?
A: Two ACM8 modules are pre-installed, providing 8 individually managed, supervised outputs for connecting electric locks, readers, or other access control field devices.
Q: Is the MAXFIT77L UL listed?
A: Yes, the MAXFIT77L is a UL-listed assembly, which simplifies AHJ approval during inspections. Verify the applicable UL standard for your jurisdiction's access control power supply requirements.
Q: What are the physical dimensions and weight of the MAXFIT77L?
A: The cabinet measures 6.25 x 15.50 x 20.50 inches and weighs 25.75 lbs. Plan for adequate wall or rack space and ensure your mounting surface can support the weight with batteries installed.
The MAXFIT77L is the unit I reach for on mid-sized commercial access deployments where the AHJ will scrutinize the power distribution chain. The pre-integrated dual ACM8 configuration — delivering 10A at 24VDC across 8 supervised outputs — means you arrive on site with a listed assembly rather than a collection of parts that need field-proving. That distinction matters when your inspection window is a one-day affair.
Technical Highlights:
- 10A @ 24VDC Output: Enough aggregate current to handle 8–12 electric locks or strikes at typical load profiles (500mA–1A each), without oversubscribing a single supply or requiring a secondary distribution panel.
- Dual ACM8 Pre-Installed: Two ACM8 modules ship inside the same enclosure — saves roughly half a day of field assembly versus sourcing, mounting, and wiring two separate ACM8 units with their own enclosures.
- 12–24V AC or DC Input Range: The wide input acceptance window means this unit can interface with transformer infrastructure that wasn't spec'd for a uniform voltage — useful on retrofit projects where building power infrastructure wasn't installed by your team.
Deployment Considerations:
- The BC750 enclosure accepts standby batteries but does not include cells — calculate your required holdover time (typically 4–24 hours depending on jurisdiction) and size the battery bank before the installation date, not on it.
- At 25.75 lbs empty, factor battery weight into your wall-mount calculations; a fully loaded unit with large SLA cells can approach 50+ lbs — use appropriate anchoring hardware rated for the total installed weight.
The MAXFIT77L is the right call for a 6–8 door commercial retrofit in an existing IDF closet where space is constrained and the AHJ demands a listed power assembly at every distribution point — not a general-purpose panel with afterthought power modules bolted on.
