Altronix R1042ULADA Rack-Mount NAC Power Extender, 10A 4-Circuit
Overview
The Altronix R1042ULADA is a UL Listed, NFPA 72-compliant notification appliance circuit (NAC) power extender purpose-built for rack-mount fire alarm infrastructure. Delivering 10A at 24VDC across four independently supervised Class A or Class B circuits, it addresses the most common integration challenge in large commercial fire systems: your fire alarm control panel simply cannot drive enough current to power all the horns, strobes, and combination devices across a multi-zone building. The R1042ULADA offloads that burden cleanly, fitting into a standard 19-inch rack in a 3U footprint and handling standby battery backup without requiring a separate charger or enclosure.
This unit draws from a standard 120VAC/60Hz, 5A feed — typical commercial building power — and converts to the regulated 24VDC that drives UL-listed notification appliances. Each of the four outputs delivers up to 2.5A, so you can balance circuit loading across zones without pushing any single leg near its limit. A 1A auxiliary output is also available for compatible panel signaling or supervisory devices.
Key Features
- 10A Total Alarm Output at 24VDC: Extends the notification capacity of virtually any FACP that runs short on current. A single unit can support high-draw strobe-heavy zones that would otherwise require panel upgrades or additional modules.
- Four Class A or Class B NAC Circuits: Each circuit is independently supervised and configurable for Class A (Style Z, four-wire loop) or Class B (Style Y, two-wire), giving installers flexibility to match the panel's wiring topology without rewiring the field device side.
- 2.2K Ohm EOL Resistors: Supervision uses the industry-standard 2.2K EOL value, which is compatible with the overwhelming majority of North American FACP brands — no special resistor kits required on most jobs.
- Form C Trouble Output, 1A/28VDC: Feeds a fault signal directly back to the FACP or building management system. If any supervised condition — AC fail, low battery, battery presence, or loop fault — trips, the trouble relay closes and the panel sees it immediately.
- Four-Point Supervision (AC Fail, Battery Presence, Low Battery, Loop): Full-time monitoring across all critical failure modes means you are not flying blind between inspections. AHJ inspectors routinely check for exactly this coverage.
- 1000 Ohm Ground Fault Test Impedance: Built-in ground fault detection at 1K Ohm impedance satisfies NFPA 72 Class A wiring requirements without external test equipment during commissioning.
- Sealed Lead-Acid or Gel Battery Support (12VDC, 7AH or 12AH): The onboard charger accepts either chemistry in both common standby capacities. A 12AH battery provides substantially longer standby runtime for systems in jurisdictions requiring 24-hour or 60-hour standby.
- Rack-Mount 19-Inch Form Factor, 3.375" H: Integrates cleanly into fire alarm or AV/security rack builds. The 26.5-inch depth accommodates internal battery installation without a separate enclosure, keeping the rack footprint predictable.
- 0°C to 49°C Operating Range, up to 85% Humidity: Covers mechanical rooms, telecom closets, and equipment rooms typical in commercial and industrial facilities — though this is not rated for outdoor or uncontrolled environments.
Integration & Compatibility
The R1042ULADA is designed to integrate with UL Listed FACPs that output a compatible NAC sync protocol. Confirm your panel's sync protocol (Wheelock, System Sensor/Cooper, Gentex, or Potter) matches the strobe synchronization module in use — the power extender itself passes the NAC signal but does not generate sync independently. Review the Altronix compatibility guide or consult pre-sales engineering before specifying for panels with proprietary sync requirements. For broader fire alarm power options in the Altronix line, the Altronix power and access control catalog covers rack and wall-mount variants across current ranges. Pair with an appropriate fire alarm control panel and verify the NAC extender is listed for use with your specific FACP model per the panel's installation manual.
Frequently Asked Questions
Q: What agency listings does the R1042ULADA carry?
A: The R1042ULADA is UL Listed, CSFM (California State Fire Marshal) Approved, and NFPA 72 Compliant — the standard certification stack required for commercial fire alarm system components in most U.S. jurisdictions.
Q: Can this unit be used with both Class A and Class B NAC wiring?
A: Yes. Each of the four output circuits is independently configurable for Class A (Style Z, four-wire supervision) or Class B (Style Y, two-wire) topology, so you can mix circuit types within a single unit to match your building's wiring infrastructure.
Q: What battery types and sizes are supported?
A: The R1042ULADA accepts 12VDC sealed lead-acid or gel batteries in either 7AH or 12AH capacity. Battery selection should be based on your jurisdiction's required standby duration — consult NFPA 72 Chapter 10 and local AHJ requirements.
Q: Does the R1042ULADA work with any fire alarm control panel?
A: It is designed for use with UL Listed FACPs. Compatibility depends on the panel's NAC sync protocol. Confirm the strobe synchronization protocol (Wheelock, System Sensor, Gentex, etc.) aligns with the notification appliances on each circuit before specifying.
Q: What does the trouble output signal cover?
A: The Form C trouble relay (1A/28VDC) activates on four supervised conditions: AC power fail, battery presence fault, low battery, and NAC loop open/short. All four are continuously monitored, satisfying NFPA 72 supervisory requirements.
The spec I always check first on a NAC extender is per-circuit current, and the R1042ULADA lands at 2.5A per output — that is enough headroom to drive a strobe-dense corridor without stacking two outputs in parallel, which simplifies your as-built documentation considerably. I have specified this unit on multi-tenant commercial builds where the base FACP was sized for the panel budget, not the notification load, and the R1042ULADA closed the gap cleanly in rack without requiring a separate battery enclosure.
Technical Highlights:
- 10A Total / 2.5A Per Circuit: Four circuits at 2.5A each let you balance strobe-heavy zones independently; losing one circuit to a ground fault does not pull down adjacent zones.
- Four-Point Supervision: AC fail, battery presence, low battery, and loop supervision all feed the Form C trouble relay — AHJ inspectors get a verifiable supervision record without installing additional modules.
- 12AH Battery Compatibility: Accepting a 12AH gel or SLA battery in the same enclosure means you can meet 60-hour secondary power requirements on certain occupancy types without a separate rack unit.
Deployment Considerations:
- Verify NAC sync protocol compatibility with your FACP before ordering — the R1042ULADA passes the panel sync signal but does not generate it; a protocol mismatch will cause strobe flash-rate violations under NFPA 72 Table 18.5.4.3.1.
- Operating temperature ceiling is 49°C (120°F): adequate for most conditioned telecom rooms, but confirm mechanical room temps in facilities with intermittent HVAC — sealed battery performance degrades at elevated temperature well before the unit's rated limit.
This unit is the right specification for mid-to-large commercial tenant build-outs and campus buildings where a single FACP serves multiple notification zones and the panel's internal NAC capacity was sized conservatively — exactly the scenario where adding a rack-mount extender is cleaner and cheaper than a panel swap.
