SDC Security Door Controls MC-4PAK 4-Door Access Controller

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.