We take cryptocurrency — so the coins you hold can buy real hardware.Pay in crypto, spend it on real hardware. Free insured shipping worldwide over $399. Plain, unbranded boxes, sent from Germany.Free insured shipping over $399. Your rate is locked for 30 minutes once checkout opens.Rate locked 30 minutes. Every item sealed, serial-checked and covered by a 24-month warranty.Sealed, 24-month warranty.

Saved items Sign in
Black rectangular motion detector with rounded corners

SDC SECURITY DOOR CONTROLS

SDC SECURITY DOOR CONTROLS MD31DB Motion Detector Black with Time Delay

SKU CH-PWWF-H9F7X

A black motion detector with adjustable time delay for access control and security systems

  • Motion detection with adjustable time delay for customised coverage
  • Black finish blends discreetly into door frames and entryways
  • Designed for access-control and surveillance accessory installations
  • SDC Security Door Controls engineering for reliable performance
  • Model MD31DB listed by manufacturer in 2021

Motion detector with time delay

The SDC Security Door Controls MD31DB is a black motion detector that includes an adjustable time delay function. It is designed for integration into access-control or security systems that require presence detection before triggering a door release or alarm input. Installers can use it to add reliable motion sensing to commercial or residential entry points.

Suited for access-control integration

This device suits installers who need a standalone detector with a built-in delay timer for door-hold or request-to-exit applications. It is not intended for users who want a camera-based sensor, a wireless battery-powered unit, or a detector that communicates over a smart-home protocol such as Zigbee or Z-Wave.

Behaviour under continuous operation

The detector maintains its detection pattern and delay timing during extended periods of use without requiring a reset cycle. Performance remains consistent when the unit is powered continuously in a high-traffic doorway, and the time delay continues to function accurately across repeated activation events.

Highlights

  • Motion detection with adjustable time delay for customised coverage
  • Black finish blends discreetly into door frames and entryways
  • Designed for access-control and surveillance accessory installations
  • SDC Security Door Controls engineering for reliable performance
  • Model MD31DB listed by manufacturer in 2021

Specifications

BrandSDC SECURITY DOOR CONTROLS
ModelMD31DB

Questions about this item

Does the MD31DB need a separate power supply or can it run from the access control panel?

The detector requires an external power source; connect it to the panel’s auxiliary output following the wiring diagram.

Will the MD31DB trigger correctly when mounted beside an older magnetic lock?

Yes, the passive infrared sensor detects motion independently of the lock’s electromagnetic field.

How can I verify the time delay is active after wiring the MD31DB?

Walk through the detection zone; the output should stay high for the preset interval before resetting.

Also in this aisle

People compared these

Same shelf, same checkout — eight coins and a 30-minute rate lock.