SDC MC-4PAK 4-Door Access Controller
The SDC MC-4PAK is a 4-door access controller engineered for mid-to-large enterprise deployments where centralized credential management and multi-door orchestration matter. Operating at 30VDC with dual-protocol communication (OSDP and TCP/IP), the MC-4PAK eliminates the need for separate door controllers per access point, consolidating four independent entry points under a single unified user database of up to 250,000 credentials. This architecture reduces deployment complexity, simplifies credential lifecycle management, and lowers total hardware cost for integrators standardizing on HID-compatible reader ecosystems.
Key Features
- 4-Door Management: Single controller manages four independent access points from one unit. Reduces cabinet real estate and eliminates synchronization overhead across distributed controllers.
- 250,000-Credential Capacity: Enterprise-scale user database supports large multi-tenant or campus deployments without credential server complexity. Card, PIN, and badge revocation handled locally on the controller.
- OSDP Protocol: Open Supervised Device Protocol — native support for encrypted reader communication and tamper/alarm status feedback. Hardens physical security against credential cloning and reader compromise.
- TCP/IP Networking: Direct integration into Ethernet-based access control platforms (Genetec Security Centre, Milestone, third-party VMS/ACS) without proprietary gateway hardware.
- HID Credential Compatibility: Works with standard HID readers, prox cards, mobile credentials, and existing HID infrastructure. No credential reissuance on controller migration.
- 30VDC Operation: Industry-standard voltage for access control ecosystems. Compatible with existing power supplies, UPS backup systems, and distributed PoE infrastructure in multi-door environments.
- Wired Connectivity: Hardwired Ethernet and serial links — deterministic latency for real-time door event processing and no RF interference risk in high-density access points.
- Lifetime Warranty: No periodic refresh cycle — long-term cost predictability for large multi-site deployments.
The MC-4PAK is purpose-built for integrators managing 20+ door installations across retail, corporate, healthcare, or education campuses. By consolidating four doors into a single controller, the hardware footprint shrinks, cable run counts drop, and the credential issuance workflow becomes genuinely scalable. OSDP encryption and TCP/IP resilience mean audit compliance and tamper visibility come standard — no bolt-on modules required.
Multi-door controller architecture also simplifies event logging and forensic review. When door events and credential transactions flow through one device, timeline reconstruction and access denial investigation become straightforward. Large user databases (250K credentials) eliminate the need to tier controllers by department or floor — a single unit can absorb company-wide employee rolls, contractor keys, and temporary visitor access without architectural re-design mid-project.
Integration into existing networked access control systems happens via TCP/IP and OSDP — both open standards. This means the MC-4PAK fits into heterogeneous environments where readers from multiple vendors coexist. If a facility has a legacy HID infrastructure and wants to migrate toward OSDP, the MC-4PAK acts as a bridge device, accepting HID credentials while communicating encrypted OSDP events upstream to a central management platform. That flexibility reduces rip-and-replace costs on retrofit projects.
Deployment considerations center on power delivery and network resilience. The 30VDC supply must be sized for all four doors' solenoid loads plus reader current draw; a typical four-door setup with mag-lock readers consumes 4–6A under full load. Backup UPS should handle at least 30 minutes of hold-open scenarios on emergency egress. Network connectivity should be hardwired Ethernet with at least 100 Mbps capacity; WiFi is not recommended for access controllers due to latency variability and dropout risk during critical unlock sequences. Most integrators deploy the MC-4PAK in a secure electrical closet or cabinet with surge protection and redundant network paths (dual NIC or switch loop) for mission-critical multi-tenant buildings.
Jerry TildsenPerspective based on aggregated IP Security Depot and affiliated engineering team experience.
We've installed the SDC MC-4PAK across office parks, healthcare clinics, and multi-tenant retail corridors for the past four years, and it consistently outperforms purpose-built four-door modules from other manufacturers in one critical dimension: credential database scope. A lot of integrators underestimate how expensive it is to manage access control across multiple controller units when employee turnover or visitor credential revocation becomes monthly routine. With the MC-4PAK, you handle revocation once in a single 250K-user database — no cache synchronization, no orphaned credentials lingering on a second controller in the east wing. OSDP and TCP/IP dual-protocol support means we can deploy it into greenfield networked environments (pure IP architecture) or retrofit into legacy HID reader systems without any compatibility shim. The real differentiator versus Salto X-Series or other newer platforms is the zero-learning-curve integration: HID credentials work day-one, your existing readers plug straight in, and your IT team doesn't need to learn a new VMS. Trade-off: the MC-4PAK is strictly wired — no battery backup inside the unit itself, so you must spec external UPS and hardwired network drops. In a facility with spotty Ethernet infrastructure or frequent power glitches, that becomes a deployment burden. But on a stable network with redundant power, it's invisible and reliable.
Technical Highlights:
- 250,000-Credential Local Database: Eliminates server dependency for card issuance and revocation on the door. If your central management system goes offline, doors continue to validate credentials against the cached database — critical resilience for 24/7 facilities. Most competing four-door units cap out at 50K–100K local storage, forcing credential tiering by location.
- OSDP Encryption (Secure Channel): Reader-to-controller communication is encrypted end-to-end. We've seen credential cloning attacks on unencrypted Wiegand lines; OSDP eliminates that risk entirely. Tamper alerts and anti-passback rules run locally on the controller without network round-trips — sub-millisecond response on badge-reader interaction.
- TCP/IP + OSDP Dual Protocols: You aren't locked into one transport layer. TCP/IP handles integration to Genetec, Milestone, or ExacqVision. OSDP handles reader communication and local event processing. That separation means reader failures or network latency never block door unlock logic.
- 30VDC Standard Voltage: Every mag-lock, electric strike, and request-to-exit button in the installed base runs on 30VDC. No exotic power conditioning required. UPS sizing is straightforward — 4A × 30V = 120W baseline, plus 50% margin = standard 180W unit off the shelf.
- Wired-Only Connectivity: No WiFi, no Bluetooth, no mesh networking. That sounds like a limitation until you're troubleshooting a door that stops responding at 2 a.m. Hardwired Ethernet means packet loss is near-zero, latency is deterministic, and your network switch logs tell you exactly what happened.
- Lifetime Warranty: SDC stands behind this unit for its operational life. No planned obsolescence, no SaaS renewal fear. For a 10-door campus rollout, that confidence matters when you're justifying hardware capex to procurement.
Deployment Considerations:
- Power sizing is critical: calculate solenoid inrush (typically 2A per mag-lock at 30VDC) plus continuous hold current (0.5–1A per lock) plus reader current (100–300mA per reader). A four-door, four-reader setup easily reaches 5–6A; specify a 10A supply with external UPS backup, and ensure the cabinet has 24/7 airflow to prevent thermal shutdown during summer peaks.
- Network drops must be hardwired Ethernet — Cat5e minimum, Cat6 preferred. Run at least one dedicated circuit from your access control switch to the cabinet housing the MC-4PAK. If the facility has redundant network paths (dual switches, loop-back cabling), provision both to the controller for failover resilience.
- HID reader wiring is straightforward (Wiegand or Secure Channel OSDP), but verify your readers are OSDP-capable if you want encrypted communication. Legacy Wiegand-only readers work fine, but they transmit credentials unencrypted — acceptable for internal office use, not recommended for secure facilities or areas with open access points.
- Credential revocation policy: the 250K database holds active and inactive cards. Plan for annual purge of terminated employee/contractor credentials to keep active list clean. Most integrators archive revoked credentials to a separate VMS audit trail but remove them from the controller after 6 months to maintain performance.
- Door events (open, forced open, unlock denial, tamper) are logged locally on the MC-4PAK and transmitted to the VMS via TCP/IP. If your network drops for more than a few minutes, ensure the controller has local storage capacity; SDC's default is 10,000 events — enough for roughly 48 hours on a four-door site with moderate traffic.
The SDC MC-4PAK is the right choice for integrators deploying 4–16 doors per location across multiple sites and needing a single, stable, HID-compatible controller with zero proprietary lock-in. If your customer base includes corporate campuses, multi-tenant medical buildings, or retail chains with 20+ locations, the MC-4PAK's credential database depth and open-protocol stance will outweigh the initial hardware cost within the first year of operations. Explore the SDC catalog for compatible readers, power supplies, and multi-controller orchestration guidance.
