Altronix MAXFIT33F Dual-Output Supervised Power Supply System

The Altronix MAXFIT33F is a dual-channel, expandable power supply system housed in the BC750 enclosure — purpose-built for security integrators who need flexible 12VDC and/or 24VDC power distribution with full supervision in a single wall-mount cabinet. Each of the two independent power supply/charger modules delivers up to 6A, giving you configuration options that match the actual load mix of your installation: two 12VDC zones, one 12V and one 24V zone, or dual 24VDC outputs. For access control and IP camera installations where device voltage requirements vary by location, that flexibility eliminates the need for separate enclosures.

Overview

The MAXFIT33F draws from 120VAC/60Hz mains and provides non-power-limited DC outputs through two independent power supply channels. A separate auxiliary power-limited output rated at 1A is available for supervised or lower-current devices. Input is protected by a 5A/250V fuse, and each output is filtered and regulated with over-voltage protection — the combination that keeps downstream cameras, readers, and control panels from seeing transients that cause nuisance resets or premature failure.

The BC750 wall-mount enclosure accommodates up to four 12VDC/12AH sealed lead-acid or gel-type batteries, giving you substantial standby capacity without sourcing a second enclosure. Batteries are sold separately, but the charger is built in — so you're buying a complete backup power platform, not a power supply that also happens to fit a battery. If your jurisdiction or site spec calls for 40AH or 65AH, Altronix supports those configurations in a separate enclosure.

Key Features

Dual independent 6A outputs: Each supply module operates independently at up to 6A — deploy two 12VDC zones, mix 12V and 24V, or run dual 24VDC. For multi-door access control panels that mix 12V locks with 24V readers, this eliminates a second enclosure and its associated wiring run.

Form C supervision on AC and battery: Both AC failure and battery status are reported via Form C contacts. That means your panel or monitoring system gets a dry-contact change-of-state — not just a voltage level — so supervision integrates cleanly into existing annunciation circuits without additional conversion hardware.

Deep-discharge battery protection: The charger automatically shuts down DC output terminals if battery voltage drops below 71–73% (12V units) or 70–75% (24V units). Over a multi-day outage, that protection extends battery life significantly — gel and SLA batteries that deep-cycle repeatedly see accelerated capacity fade, and this circuit prevents that.

Instantaneous failover on AC loss: The system transfers to battery backup without a delay window. For door controllers and access readers, a power gap of even 200ms can cause a controller reset and a temporary loss of door state — instantaneous failover eliminates that scenario.

Four-battery capacity in the BC750 enclosure: The wall-mount cabinet fits up to four 12AH/12VDC batteries. At 12AH each, a fully loaded cabinet gives you 48AH of standby — enough runtime on a moderate load to satisfy most high-rise or commercial UL 294 standby requirements without a separate battery box.

Fire alarm disconnect supervision: The unit includes a supervised fire alarm disconnect with selectable latching or non-latching operation and a 10K EOL resistor. For integrated fire/access systems, this is a code-driven requirement — having it factory-built into the power supply means one fewer field-wired supervisory circuit.

Aux 1A power-limited output: The unswitched auxiliary output stays on regardless of DC output state, useful for powering supervisory circuits or low-draw devices that need to remain live during a fault condition.

LED status indicators: Discrete LEDs confirm 120VAC presence and DC output state at a glance during commissioning and service calls — no meter required for a basic go/no-go check.

Operating range 0°C to 49°C: Rated for standard indoor environments. The storage range extends to -20°C / 70°C, which matters if the unit spends time in a contractor's van or an unheated staging area before installation.

Integration & Compatibility

The MAXFIT33F is compatible with the LINQ2 Network Communication Module, which provides remote diagnostics, control, and reporting of power supply status — useful on enterprise campuses or managed service contracts where a site visit to check power health is cost-prohibitive. The LINQ2 is listed as an accessory and is sold separately.

The enclosure is a wall-mount indoor unit dimensioned at 16.5