Camden CM-810 SPDT Momentary Strike

We've installed the Camden CM-810 across dozens of access control retrofits and new builds, and the momentary-action design consistently outperforms maintained strikes in real-world deployments. The operational benefit is straightforward: when you're managing power distribution across 8–16 door strikes in a single panel cabinet, the difference between always-on and pulse-only current draw translates directly to supply sizing, thermal management, and component lifespan. On a recent 12-door installation in a mid-rise office building, switching from maintained to momentary strikes allowed the integrator to downsize the UPS from 2kVA to 1.5kVA — a non-trivial cost and footprint reduction. The 6A contact rating is more than adequate for standard electromagnetic strikes; we've never seen contact degradation or nuisance lockouts on systems within rated duty cycle. The chief trade-off versus more sophisticated multi-function strikes is the lack of status feedback — the CM-810 is purely output-driven, so you cannot monitor strike armature position or detect a door forced open from the strike itself. Pair it with a separate door position sensor if forensic accountability or forced-entry alarming is required. Temperature rating is conservative but honest; we don't recommend these for unheated vestibules or sun-baked exterior applications without a weatherized enclosure. Cycle-life expectations are realistic at 100,000 operations — that's 27 cycles per day for a year, or sustained use on a medium-traffic exit. Main entrances and high-security mantrap doors with 50+ cycles per day will approach end-of-life in 12–18 months; budget accordingly and have a spare on the shelf.

Technical Highlights:

• SPDT Contact Configuration: Momentary switching eliminates the sustained coil power and thermal overhead of latching strikes. For systems managing multiple strikes on a single 24VDC supply, this translates to smaller gauged feeder wire, lower voltage drop, and measurable power savings in 24/7 operations.
• 24VDC Isolation from Logic Circuits: The strike power return must be isolated from reader signal ground to prevent noise injection into card-reader or biometric-sensor circuits. We've seen intermittent authentication failures traced to poor power distribution discipline — keep the strike return on a separate bus bar from the logic-level returns.
• 100,000-Cycle Life at Rated Duty: This is a mid-range metric. High-traffic doors (corporate main entrance, hospital ER vestibule) will see accelerated wear. Extended-duty variants exist; request a quotation if your application exceeds 30 cycles per day.
• Wall and Pole Mount Flexibility: Both profiles are standard in the field, but the mounting hardware is a separate kit — confirm it's included or budgeted in your BOM. Frame and mullion fitment is straightforward; pole-mount requires a reinforced collar or bracket depending on pole diameter.
• Temperature Operating Window −25°C to +75°C: Indoor controlled environment — this is the assumption. Exterior or unheated-space installations need thermal enclosure or derating analysis.

Deployment Considerations:

• Momentary strikes require a momentary relay output from your access control panel — verify this is available before ordering. Some older wiegand-only panels must be retrofitted with a relay module; confirm panel capability in the engineering phase.
• Do not daisy-chain multiple strikes on a single momentary contact. Each strike must have its own isolated relay coil circuit to avoid voltage sag and unpredictable lockout behavior. This increases wiring complexity but is non-negotiable for reliability.
• The 24VDC supply must be clean and isolated from low-voltage logic signaling. Use separate conduit, separate terminal blocks, and separate grounding for power and logic circuits. Noise on the 24VDC return will couple into reader circuits and cause sporadic authentication failures.
• Wire gauge scales with run length. For runs beyond 50 feet, verify voltage drop at the strike terminal using I²R loss calculation. A 2-wire run of 100 feet at 6A draw in 18AWG copper will drop approximately 1.2V — unacceptable for reliable strike activation. Step up to 14AWG or shorter conduit runs.
• Cycle life is finite — budget replacement on 18-month cycle for high-traffic exits. Keep spare coils or full strike units in inventory if the door is business-critical.

The CM-810 is the right choice for integrators building multi-door access control systems where power efficiency, thermal management, and long-term reliability matter more than feature density. For single-door installations or applications requiring status feedback and extended duty cycles, consider Camden's maintained-action or multi-function strike portfolio. Explore additional options in the Camden catalog.