Camden CM-850 Remote Door Release Switch SPDT

The Camden CM-850 is a remote door release switch designed to integrate electromagnetic lock systems into access control deployments. It delivers SPDT (Single Pole Double Throw) contact functionality in both momentary and maintained operating modes, giving you flexibility in how long the strike remains energized during credential-based access events. Operating at 12VDC, the CM-850 connects directly to HID reader infrastructure and standard electromagnetic strike hardware, eliminating the need for separate relay modules in smaller to mid-sized installations.

Key Features

• SPDT Contact Configuration: Single Pole Double Throw means the switch can control two independent circuits — typically one energizing the strike on access grant, the other handling monitoring or auxiliary functions. This reduces auxiliary relay count and simplifies wiring in modular access control designs.
• Momentary and Maintained Modes: Momentary mode holds the strike open only while the credential is actively present; maintained mode energizes the strike for a fixed duration after release command. Choose based on your door hardware spec and entry-flow requirements.
• 12VDC Operating Voltage: Operates directly on standard 12VDC control power supplied by most commercial access control systems. No exotic power conditioning required — integrates into existing 12VDC rails in your access control panel.
• Electromagnetic Lock Compatibility: Designed for use with electromagnetic locks and strikes commonly deployed in commercial entry points. The CM-850 handles the switching logic; your strike hardware provides the holding force.
• HID Credential System Ready: Integrates with HID reader infrastructure (card, badge, PIN, or multi-factor credential) and standard access control wiring practices. Suitable for installations targeting 50-door commercial or institutional deployments using credential-based access.
• Commercial Integrator Class: Built for security integrators and IT architects installing access control across multiple doors in the same facility. Supports standard rack and panel mounting in access control enclosures.

Integration and Deployment Context

The CM-850 fits naturally into modular access control topologies where credential readers trigger door release decisions at the controller level. Install the switch inside your access control panel or in a weatherproof auxiliary enclosure near the strike hardware, depending on your wiring run and electrical code requirements. Because it operates at 12VDC and supports both momentary and maintained switching modes, you can deploy it in environments ranging from office building entry vestibules to warehouse receiving doors without hardware redesign — the mode selection changes behavior without changing the physical installation.

In larger deployments, the access control systems page provides context on how door release switches integrate with controller logic, reader assignment, and audit trail capture. For wiring guidance specific to your credential reader type and strike hardware, consult your integrator's access control integration guide.

Frequently Asked Questions

Q: Does the CM-850 work with non-HID credential systems?

A: The CM-850 is a passive SPDT switch — it operates with any access control system that outputs a 12VDC momentary or maintained signal. HID readers are one common source; Salto, Allegion, and other brands with 12VDC dry-contact outputs will work equally well. Verify your system delivers 12VDC to the switch input.

Q: What is the difference between momentary and maintained mode on the CM-850?

A: Momentary mode energizes the strike only while the access event signal is active — typically 1–2 seconds after credential validation. Maintained mode holds the strike energized for a timer-controlled duration set in your access control panel (often 10–30 seconds). Momentary suits high-traffic entry points; maintained suits areas where users need extended time to push through doors with heavy springs.

Q: Can the CM-850 be used outdoors?

A: The CM-850 is rated for indoor use in standard commercial environments. For outdoor strikes or weatherproof applications, install the switch inside a climate-controlled access control enclosure and run protected cabling to the outdoor strike hardware.

Q: Is the CM-850 suitable for fire-rated doors?

A: Fire-rated door release is a code-governed application. Verify with your authority having jurisdiction (AHJ) and fire code official that electromagnetic strikes and remote release switches meet your local fire, egress, and life-safety rules. The CM-850 itself is a standard switch; code compliance depends on system design and door hardware certification.

Q: How many doors can a single CM-850 control?

A: One CM-850 switch controls one electromagnetic strike or lock. For multi-door deployments (50 doors, for example), you provision one CM-850 per door, typically installed in your main access control panel or in distributed auxiliary panels near strike hardware clusters.

Ted Perry

Perspective based on aggregated IP Security Depot and affiliated engineering team experience.

The CM-850 is a straightforward, purpose-built switching element for credential-based door release — no bloat, no integrated intelligence. It does one job: translate a 12VDC access grant signal into a clean SPDT contact closure that energizes an electromagnetic strike. In mid-sized commercial deployments (think office parks, institutional buildings, light warehouse access), this simplicity is an asset, not a limitation.

Technical Highlights:

• SPDT Configuration: Two independent pole-throw pairs mean you can simultaneously energize a strike on one pole and route monitoring or alarm feedback on the other — reduces relay overhead and keeps your access control panel wiring cleaner and easier to audit.
• Dual Mode Switching (Momentary and Maintained): Momentary respects high-traffic user flow (door open only while credential active), while maintained mode accommodates mechanical constraints (heavy door springs, delayed entry mechanisms) — configure per-door based on hardware, no board revision needed.
• 12VDC Direct Integration: Operates on voltage already present in your access control panel. No isolated 24V supply, no step-down transformer — one less failure point and one fewer power rail to budget.

Deployment Considerations:

• Indoor Environment Only: The CM-850 itself is not sealed for outdoor mounting. If your strike is outside, mount the switch indoors and run shielded control cabling to the strike through conduit — adds labor but avoids moisture ingress into the switching contacts.
• One-to-One Mapping: One CM-850 per door means multi-door deployments require inventory at scale. For 50-door sites, you're provisioning, installing, and labeling 50 switches — budget accordingly in labor and spare parts stock.
• Code Compliance Verification Required: Fire-rated doors, egress paths, and accessible entry require fire marshal and AHJ sign-off on the release mechanism. The switch itself is code-neutral, but your system design (held-open duration, fail-safe relay logic, backup power path) must meet NFPA and local fire codes. Work with your fire consultant early.

Position the CM-850 in commercial access control projects where credential readers drive door release, door count is moderate (25–100 doors), and your integrator team is provisioning and testing per-door electronics as part of standard commissioning. It's the right choice for IT architects or security integrators handling modular deployments where simplicity and known wiring patterns reduce risk and speed installation timelines.