Altronix MAXIMAL77 Access Power Controller with Integrated Power Supply
Overview
The Altronix MAXIMAL77 is a comprehensive access control power management solution designed for security integrators and system installers who require reliable power distribution and relay switching in a single compact enclosure. This access power controller combines a regulated dual-output 24VDC power supply with integrated charger functionality and 16 independently fused relay outputs, all housed in the industry-standard BC800 enclosure. The MAXIMAL77 delivers 9.7 amperes per supply rail, providing sufficient power for mid-to-large scale access control deployments, door readers, locks, and ancillary devices.
Key Features
- Dual 24VDC Power Supplies: Two independent 24VDC regulated outputs, each rated at 9.7A, enable segregated power distribution and redundancy in access control topologies
- 16 Fused Relay Outputs: Each relay output is individually fused, protecting downstream circuits and allowing selective load isolation without system-wide shutdown
- Integrated Charger: Built-in battery charging capability supports backup power configurations for continuous operation during mains loss
- 115VAC Input: Standard North American single-phase AC input voltage simplifies installation and reduces transformer requirements
- BC800 Enclosure: Compact, wall-mountable steel enclosure with professional finish suitable for electrical closets, telecommunications rooms, and secure areas
- Industrial-Grade Construction: Heavy-duty relay contacts and power distribution bus rated for continuous access control duty cycles
Technical Operation
The MAXIMAL77 accepts 115VAC mains input and conditions it through a transformer-isolated power supply stage to produce two synchronized 24VDC rails at 9.7A each. This dual-supply architecture permits independent control of access door systems, panel-mounted readers, and electric locks without cross-talk or voltage sag affecting parallel devices. All 16 relay outputs are SPDT (single-pole double-throw) contact form, allowing normally-open or normally-closed logic per application requirement. Each relay is backed by individual fuses rated for the relay coil current, preventing single-load failure from disabling the entire output bank. The integrated charger maintains connected backup batteries (typically lead-acid or lithium), ensuring continued lock release and reader power during utility outages.
Installation & System Integration
The MAXIMAL77 mounts in vertical or horizontal orientation within the BC800 enclosure, with screw terminals for 115VAC input and Class 2 output connections (24VDC, relay common, and relay normally-open/normally-closed pairs). Wire terminals accommodate 10–12 AWG copper conductors, supporting standard commercial low-voltage installation practices. The dual 24VDC outputs can be wired in parallel for doubled amperage (19.4A combined) where load analysis permits, or kept separate for redundant, non-interacting subsystems. Relay outputs integrate directly with door strike solenoids, maglocks, request-to-exit sensors, and auxiliary switching logic without intermediary relays in most single-door and multi-door topologies.
Applications
The MAXIMAL77 serves mid-scale access control projects including multi-door office environments, secure facilities, parking access systems, and building automation integrations where simultaneous power distribution and relay switching are required. Its dual-supply design is particularly suited to architectures where redundancy or load segregation demands isolation between access zones or reader banks.
Ted PerryPerspective based on aggregated IP Security Depot and affiliated engineering team experience.
In my experience deploying mid-scale access control systems, the Altronix MAXIMAL77 offers a practical balance between power capacity and relay switching density. The dual 24VDC supplies at 9.7A each handle typical reader and locking hardware loads without requiring additional step-down supplies, and the 16 fused relay outputs provide flexible logic control for door state monitoring, auxiliary devices, and system interlocks.
Technical Highlights:
- Dual Independent 24VDC Rails: The two 9.7A supplies allow segregated distribution, reducing risk of voltage collapse if one rail encounters a transient load spike. This is invaluable in systems with mixed-impedance readers and solenoids.
- 16 Individually Fused Relays: Each relay is independently protected, so a single shorted load or wiring fault isolates to one relay rather than cascading across the bank. This significantly simplifies troubleshooting in the field.
Deployment Considerations:
- The MAXIMAL77 requires access to 115VAC mains within the enclosure or nearby conduit. Verify site power availability before procurement.
- For systems exceeding 16 switching outputs or requiring greater than 19.4A total 24VDC capacity, plan for stacked or secondary MAXIMAL77 units with coordinated control logic.
- Integrate backup battery charging capacity into the initial design; the built-in charger accepts standard lead-acid or compatible lithium cells to maintain locks during outages.
The MAXIMAL77 is a reliable, proven choice for integrators seeking a compact, all-in-one power and relay solution. Its proven field durability and straightforward wiring make it suitable for both retrofit and new-build access control environments.
