Motion Sensor Placement Calculator

Design smarter lighting and security zones with sensors. Enter room details and get placement points. Download results in PDF or CSV for crews onsite.

Project Inputs

Use a label that matches your drawings.
Corridors use centerline spacing by default.
Target affects placement warnings and notes.
Along the main direction of travel.
Across the space or corridor width.
Used for sanity checks and notes.
Actual sensor fixing height above finished floor.
Affects the conservative coverage factor.
Wall mount uses a sector coverage model.
Typical: 90–180. Ceiling lenses may vary.
Use manufacturer rating for your mount height.
Higher overlap reduces blind spots, adds sensors.
Shelving, partitions, machinery, or columns.
Used for notes only; test at real traffic speed.
Keep sensors away from walls to avoid dead zones.
Optional: add heat sources, pets, partitions, or airflow issues.
Reset
Tip: After marking points, perform a walk test and adjust angles. Always follow local codes, safety rules, and manufacturer guidance.

Example Data

Scenario Length (m) Width (m) Mount (m) Range (m) Angle (deg) Overlap Obstructions Typical Outcome
Open warehouse bay 24 12 3.5 12 120 15% 10% Grid points with moderate overlap.
Long corridor 40 3 3.0 10 110 20% 15% Centerline points, spaced along length.
Workshop with shelving 18 10 3.2 9 100 25% 30% More points to cover blocked aisles.

Formula Used

This calculator estimates sensor quantity and spacing using a conservative floor-coverage model. Real lenses create complex patterns, so always validate on site.
TechFactor slightly increases coverage for dual-technology and microwave sensors. MountFactor reduces coverage for wall mounting due to directional limits.

How to Use This Calculator

  1. Measure room length, width, and ceiling height from drawings.
  2. Choose room type, mount type, and sensor technology.
  3. Enter the rated range and view angle from datasheets.
  4. Set overlap and obstruction allowances for your site.
  5. Click Calculate Placement to view results above.
  6. Mark coordinates on plan, then field-test walk paths.
  7. Download CSV or PDF to share with the installation crew.

Coverage Planning for Open Areas

Open floor plans benefit from sensors that create detection zones. This calculator converts room dimensions and rated range into an estimated footprint, then applies overlap and obstruction allowances to avoid unprotected pockets. Use the spacing output as a grid, and keep sensor points centered within the usable area. When the space contains multiple activity zones, split the plan into rectangles and run the tool for each zone. Confirm edge coverage before final drilling and anchoring. Update approved installer drawings.

Corridor and Aisle Detection Strategy

Long corridors and warehouse aisles work best with centerline placement. The tool switches to a corridor model so spacing follows the travel direction while staying centered across the width. Pay special attention to junctions, doorways, and turns where line of sight changes. If forklifts operate, consider slower approaches and wider coverage to reduce missed triggers at oblique angles.

Mounting Height and Angle Considerations

Mount height influences sensitivity and tamper resistance. Higher mounts reduce interference but may reduce reliable detection if the lens is not rated for that height. For wall mounting, the calculator uses a sector footprint based on view angle, which highlights blind spots near corners. When using narrow angles, aim sensors slightly away from reflective surfaces and ensure the target path crosses detection zones.

Managing Obstructions and False Triggers

Shelving, partitions, columns, and machinery reduce usable coverage. Increase obstruction allowance when the line of sight is frequently blocked, and add overlap when you need redundancy. False triggers often come from HVAC airflow, hot equipment, direct sunlight, or moving banners. Use the notes field to document known sources and confirm that chosen technology matches the environment.

Commissioning, Testing, and Documentation

After installing, perform a walk test along expected routes and confirm activation timing. Adjust sensor aim and delay settings to match the operational need, then rerun the calculator if the layout changes. Export CSV for markups and installation checklists, and save PDF results as part of the project closeout record.

FAQs

1) Should I trust the calculated sensor count without testing?

No. Use it as a planning baseline, then confirm with a walk test. Real detection patterns vary by lens, height, and thermal conditions, so field validation is essential.

2) What overlap setting is common for security-focused spaces?

Many projects start around 10–25% overlap. Higher overlap helps at junctions and near obstructions, but increases device count. Adjust after a site survey and commissioning tests.

3) How do I set obstruction allowance?

Estimate how much of the sightline is blocked by shelving, partitions, columns, or equipment. Light clutter may be 10–20%, while dense racking can reach 30–50%.

4) When is wall mounting better than ceiling mounting?

Wall mounting suits entrances, long approaches, and perimeter monitoring. It can leave corner blind spots, so check view angle and aim. Ceiling mounting usually provides more uniform coverage.

5) Why can PIR sensors miss vehicles?

PIR detects heat changes, so slow or angled vehicle movement may be less reliable. Dual-technology options can improve performance in mixed traffic areas, especially near loading bays.

6) How should I use the placement coordinates?

Plot them on your floor plan using the same origin point, then adjust for fixtures, beams, and access routes. Keep a short commissioning log, and export CSV/PDF for the crew.

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Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.