Lifesafety Power C4-BOXED Four-Output Access Control Lock Module
Overview
The Lifesafety Power C4-BOXED is a compact four-channel output module designed to distribute supervised 12VDC power to access control hardware from a centralized logic platform. Each of the four outputs carries independent 3A fusing—meaning a short or failure on one lock circuit does not cascade to the others. This isolation is critical in multi-door deployments where a single fault cannot take down perimeter or interior access control across an entire facility.
The C4-BOXED (often searched as C4 BOXED) supports both failsafe and fail-secure configuration per output, allowing mixed-mode deployments within the same installation. Some doors can unlock on power loss (failsafe, typically for emergency egress compliance), while others remain locked (fail-secure, for high-security zones) based on your building code and security requirements.
Key Features
- Four Independent 3A Fused Outputs: Each output is individually protected at 3A maximum current. This per-circuit fusing prevents a single shorted lock load (magnetic lock, electric strike, solenoid, or relay coil) from affecting the other three outputs—essential when you're controlling multiple door hardware types or brands in parallel.
- 12VDC Output Voltage: The module delivers regulated 12VDC to door control hardware, matching the voltage requirement of most commercial magnetic locks and electric strikes. Verify your main power supply voltage before wiring to ensure compatibility with your access control panel's output specification.
- Supervised Fused Supervision: The module integrates fused supervision into its output design, providing fault reporting if a fuse blows or a circuit opens unexpectedly. This visibility into circuit status helps integrators and building management detect hardware failures or tamper events rather than discovering a dead lock during a user troubleshooting call.
- Failsafe/Fail-Secure Per-Output Configuration: Configure each output independently—do not assume all four outputs behave the same way. Consult your access control panel documentation for the logic signal polarity and voltage levels required to switch each output between failsafe and fail-secure modes. This flexibility is often mandated by fire code (failsafe doors must unlock on power loss for evacuation) and security policy (secure areas must remain locked on power loss).
- Compact Boxed Enclosure: The module fits wall-mounted or cabinet-installed configurations, positioned adjacent to or remote from door hardware depending on your cable run layout. Dimensions and mounting provisions are suitable for both retrofit and new-construction scenarios.
- Third-Party Integration: The C4-BOXED integrates with Lifesafety Power control platforms and third-party access control systems that provide supervised 12VDC or 24VDC logic signals to trigger relay closures. Confirm your access control panel's output voltage and signal type match the module's input requirements before deployment.
Integration & Compatibility
The C4-BOXED accepts supervised logic signals from your access control panel to activate each of the four relay outputs. Low-voltage wiring must be run separately from AC mains cable to avoid noise coupling into logic circuits—a fundamental best practice in any access control installation. Each lock load (magnetic lock or electric strike) connects to its corresponding relay terminal pair. Do not exceed 3A per output; loads drawing more current require a dedicated external relay or second power module.
The module is FAI (Fire Alarm Interface) compatible, meaning it can integrate with fire alarm annunciation if required by code (e.g., releasing magnetic locks on all doors during an alarm event). Verify your fire alarm and access control panel support the same logic signaling standard before finalizing the design.
Installation Guidance
Each of the four outputs is fused at 3A—never attempt to bypass or upsize a fuse without understanding the actual load current. Undersized fusing leads to nuisance trips; oversized fusing defeats the short-circuit protection that prevents cascade failures. Wire lock loads with properly rated twisted pair or shielded cable depending on run length and environmental noise. Test failsafe and fail-secure modes under power-loss simulation to confirm your configuration matches your security posture before signing off the project.
Frequently Asked Questions
Q: Can I use the C4-BOXED to control 24VDC locks?
A: The C4-BOXED outputs 12VDC only. If your locks require 24VDC, you will need a different module or a separate 24VDC power supply feeding a standalone relay bank. Do not attempt to series-connect outputs or use voltage boosters—that approach introduces single points of failure and voids the per-output fusing benefit.
Q: What happens if a fuse blows on one output?
A: The fused supervision circuit signals a fault condition to your access control panel. The affected output stops supplying power to that lock, but the other three outputs continue normal operation. Replace the blown fuse only after confirming the root cause (shorted lock winding, miswired terminal, or genuine short-circuit) and correcting it. Repeat fuse failures indicate a hardware defect that requires lock or circuit inspection.
Q: Can I mix failsafe and fail-secure outputs in the same module?
A: Yes. Each output is individually configurable. Your access control panel's logic input determines the mode per output. Typical configurations include failsafe on main egress doors (fire code requirement) and fail-secure on server room or back-of-house entries (security requirement).
Q: Do I need a separate power supply to drive the C4-BOXED?
A: Yes. The C4-BOXED is an output distribution module only. It requires a dedicated 12VDC power supply (often integrated into your access control panel or provided as a standalone module) that can deliver the combined current of all four outputs plus panel logic overhead. A 5A or 10A supply is typical for four 3A lock circuits; confirm your power budget in the panel specifications.
Q: Is the C4-BOXED suitable for outdoor door hardware?
A: The module itself is designed for indoor cabinet or wall-mount installation. Outdoor locks (magnetic locks or strikes) can be controlled by the C4-BOXED provided the wiring and connectors are rated for the environment (UV-resistant conduit, outdoor-rated terminals). Consult your lock manufacturer's installation guide and local electrical code for outdoor low-voltage wiring requirements.
Q: What's the maximum cable run distance between the C4-BOXED and a door lock?
A: Standard twisted-pair low-voltage cable is suitable for runs up to 50–75 feet at 3A load current. Longer runs may require larger-gauge wire to avoid voltage drop that weakens lock actuation. Use shielded or twisted-pair cable in electrically noisy environments (near AC mains or fluorescent ballasts). Test actual voltage at the lock terminal under worst-case current draw to confirm adequate actuation voltage.
The C4-BOXED is a straightforward, field-proven distribution module that solves a real problem in multi-door access control: protecting one lock circuit from cascading failures caused by another. Independent 3A per-output fusing is not a marketing feature—it's a mandatory design choice for any facility managing four or more doors from a single power supply.
Technical Highlights:
- 3A Per-Output Fusing: Each of the four outputs is independently fused at 3A, preventing a shorted magnetic lock on Door A from pulling down power to Doors B, C, and D. In a 16-door installation with four C4-BOXED modules in series, this isolation architecture means a single hardware failure isolates to one door only—critical for uptime in multi-tenant or multi-zone facilities.
- 12VDC Supply: Matches the vast majority of commercial magnetic locks and electric strikes in production. Confirm your main power supply explicitly supports 12VDC output at 12A minimum for a full four-output deployment (3A × 4 outputs + overhead).
- Fused Supervision: Delivers real-time fault indication to your access control panel if a fuse opens. No more guessing whether a lock is dead or misconfigured—the panel tells you immediately that Output 2 is off-line.
Deployment Considerations:
- Do not undersize your main 12VDC power supply. A typical four-output deployment (magnetic locks) draws 8–12A under sustained actuation. Undersized power causes chronic voltage sag, weakening lock response and triggering false supervision faults.
- Wire separation is non-negotiable. Run low-voltage control signals and lock load cables in separate conduit or at least 12 inches apart from AC mains. Coupling noise from building power into logic circuits is the #1 cause of mysterious access control glitches integrators blame on the panel or lock instead of the installation.
- Each output supports both failsafe and fail-secure mode—but your access control panel must explicitly command each mode. Do not assume the module defaults to failsafe (many do not). Test every output under power-loss conditions before commissioning.
The C4-BOXED belongs in any multi-door installation where per-output fault isolation and mixed failsafe/fail-secure configuration are required. Typical deployments include corporate campuses (separate modules per building entrance, failsafe egress doors + fail-secure back-of-house), hospital access control (OR suite + loading dock on the same supply), and warehouse automation (multiple dock doors with mixed release logic). Not a glamorous product, but absolutely essential for reliable multi-door access control infrastructure.
