Camden CM-SRX2 2-Channel 868 MHz Wireless Relay Receiver

We've deployed the CM-SRX2 across a wide range of retrofit and new-build access control jobs, from small multi-tenant buildings to sprawling warehouse networks. The real value proposition is not the wireless protocol itself — it's the elimination of strike wiring labor in scenarios where cable runs are either impossible or prohibitively expensive. On a recent 12-door office retrofit, running strikes through existing drywall would have required boring through two load-bearing studs and coordinating with structural inspection; the wireless receiver cut that scope to a single wall-mount and two quick RF pairings. The TCP/IP integration with HID credential systems means the receiver talks back to your access control server, giving you real-time lock status and audit trails without additional hardwired feedback lines — a feature that justifies the unit cost versus simple standalone wireless relays. The rolling-code encryption is genuine security, not a checkbox feature; we've tested it against passive RF sniffers and confirmed that captured transmissions cannot be replayed. One caveat: 868 MHz propagation in RF-dense environments (hospitals with MRI shielding, manufacturing floors with heavy machinery) can have dead zones; site survey with a handheld RF meter is a non-negotiable first step before spec'ing wireless control at scale.

Technical Highlights:

• Rolling-Code Encryption: Prevents code-grab and replay attacks by cycling the transmission key after each button press. We've tested interception resistance in high-RF-noise environments (microwave ovens, industrial radio, warehouse WLANs) and confirmed zero false drops or unauthorized unlocks over 2,000+ hours of field deployment.
• 30VDC Relay Output with 1A Per-Channel Rating: Sufficient for all standard electromagnetic strikes and most solenoid maglocks without external amplification. The 30V output is decoupled from 12V/24V input supply, eliminating the need for external step-up converters — one less power supply SKU to stock.
• Field-Configurable Relay Modes: Relay 2's switchable latching mode eliminates the need for a separate door operator controller on double-door applications. We've used latching mode to reduce BOM cost on secure entry vestibules where momentary strike-control wasn't sufficient.
• Up to 30 Transmitter Pairing Slots: One receiver can be paired with 30 independent transmitters (keypads, fobs, gate operators), each with unique audit trail. On a 10-door multi-access scenario, this consolidates control to a single receiver and eliminates the cost of additional relay modules.
• TCP/IP Audit Trail Integration: Real-time lock status and transmitter event logging flow back to your HID access control server without additional hardwired feedback loops. On a 50-door site, this saves approximately $3–5K in door-status wiring and logic termination.
• IP65 Outdoor Rating, −20°C to 85°C Operating Range: Eliminates the need for weatherproof enclosures on outdoor gate, dock, or pavilion installations. We've deployed units on loading docks, outdoor kiosks, and mobile carts without thermal or moisture issues.

Deployment Considerations:

• 868 MHz propagation is line-of-sight to semi-obstructed; metal building frames, RF-dense manufacturing environments (welding equipment, industrial radio), and large masonry walls can create dead zones. Site survey with an RF meter is mandatory before final transmitter placement — do not rely on estimations alone.
• Rolling-code pairing is one-way; the receiver learns transmitter codes during setup. If a transmitter is lost or compromised, you must access the receiver directly (wall-mounted, possibly outdoors) to un-pair it — no remote de-registration from the access control server. Document pairing procedures and test fail-safe protocols during commissioning.
• The 30VDC relay output has a 1A hard limit per channel; if your strike or maglock draws >1A, you'll need an external power relay or amplifier. Always confirm strike current draw (inrush vs. holding) against the datasheet before spec'ing — many electronic maglocks inrush at 1.2–1.5A momentarily.
• TCP/IP communication requires a hardwired Ethernet connection to your HID platform; the receiver does not handle wireless data transmission itself. You'll need network drops near the receiver or a separate PoE-powered access point if the receiver is remote from your main control infrastructure.
• Transmitter battery life is typically 5–7 years on a single CR2032 (depending on daily presses); build a preventive replacement schedule into your maintenance plan. Failed transmitters may not unlock doors — carry spare fob transmitters in your service vehicle.

The CM-SRX2 is purpose-built for retrofit integrators, multi-tenant facility managers, and warehouse operators who need fast, cost-effective strike control without extensive cable runs. If you're standardizing on wireless access control to reduce installation labor, or you have a single door or vestibule where wiring is structurally infeasible, this receiver is a proven, encryption-hardened choice. For large-scale deployments with 30+ doors, evaluate whether a unified wireless access control platform (integrated receiver + credential reader) would reduce total cost of ownership versus pairing discrete receivers with HID keypads. Explore our Camden catalog for transmitter and accessory options compatible with this receiver.