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Off-white rectangular motion detector model 31

SDC SECURITY DOOR CONTROLS

SDC SECURITY DOOR CONTROLS MD-31DOW Motion Detector with Time Delay Off White

SKU CH-S8D0-9MS39

Motion detector with time delay unlocks doors immediately upon detecting a person approaching for uninhibited egress

  • Unlocks door instantly for hands-free egress when motion is detected
  • Adjustable time delay keeps door open after activation
  • Off-white finish blends with commercial door frames
  • Designed for request-to-exit access control systems

REX Motion Sensor for Door Egress

The SDC MD-31DOW detects a person approaching the door and unlocks it immediately for uninhibited egress. It is designed for access-control systems that require hands-free exit detection in commercial or institutional settings. The off-white finish suits standard interior door frames.

Time-Delay Adjustment for Tailored Hold-Open

The built-in time delay off function lets installers set how long the door remains unlocked after detection. This single adjustment prevents nuisance re-locking while maintaining security. Buyers who need a sensor without an adjustable hold-open period should choose a different model.

How it compares

Measured against everything we stock in Home Protection & Access Devices, at today’s prices. Recalculated every night.

Price $205.99
Pricier than about 80% of the 1,270 comparable items (median $64.99).

Specifications

Product
Brand nameSDC SECURITY DOOR CONTROLS
Model nameMD-31DOW

Questions about this item

What does the MD-31DOW model number indicate about how the sensor behaves in a real installation?

The MD-31DOW is a request-to-exit motion detector that unlocks the door immediately when it detects a person approaching, allowing free egress without pressing a button.

What interface does the MD-31DOW use and what does that connection limit in practice?

The sensor is wired directly to the door controller's REX input, so its only practical limit is the cable run length and the controller's voltage requirements.

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