Sensor planning, four ways: choosing the right Relux tool for the job
A well-placed PIR sensor turns a lighting installation into measurable energy savings. A poorly placed one creates blind spots, false triggers, and a permanently underused investment.
That makes sensor planning one of the highest-leverage steps in a modern lighting project, and one of the easiest to underestimate. "Sensor planning" can mean very different things depending on the project stage:
- An early-stage feasibility check for a tender
- Selecting the right detector from a manufacturer's catalogue
- Detailed 3D coverage planning with detection cones
- Integration into a full BIM workflow
Relux offers four complementary tools, each built for one of those jobs. Here is a practical guide to choosing between them.
1. SensCalc - for fast feasibility and ROI
Free, browser-based, no installation. SensCalc is the right starting point when the client asks the question every sales conversation eventually arrives at: how fast does the investment pay off?
You define a room (geometry, usage profile per EN 12464-1, installed lighting power per SIA 387/4), filter certified sensors by GTIN, brand, or mounting type, and SensCalc calculates how many sensors you need, where they go, what the energy savings are, and when the installation amortises.
The output is a customer-ready PDF with the recommended sensor count, their placement, the resulting energy savings, the payback estimate, and a per-sensor GTIN list for ordering, everything a non-technical client needs in one document.
Best for: early sales conversations, tender support, quick what-if scenarios, customers who need a one-page ROI document.
Not for: complex geometry, advanced control logic, detailed lighting calculation, BIM deliverables.
One detail that matters: nothing you do in SensCalc is throwaway. Projects export to JSON (for back-up and re-upload) or RECAD, which opens directly in ReluxDesktop for deeper planning.
2. ReluxNet - for sensor selection and product data
Before placing a sensor, you have to choose one. ReluxNet is the online database where roughly 1,000 certified PIR sensors from international manufacturers sit alongside a broad catalogue of luminaires.
You filter by mounting position, brand, technical specification, and pull data sheets, technical drawings, and mounting instructions on the spot. Files come in the formats your downstream tools expect: ROLFz, RFA for Revit, DWG for AutoCAD, IES, Eulumdat, GLDF.
Best for: product research, specification writing, comparing options across manufacturers, exporting clean product data into other planning environments.
Not for: actual coverage or savings calculation, ReluxNet is the catalogue, not the planner. Use it to find the sensor, then send it on to SensCalc, ReluxDesktop, or ReluxCAD.
3. ReluxDesktop - for detailed planning
This is where sensor planning gets serious. ReluxDesktop is the only desktop lighting planning software that plans PIR sensors with full detection-area visualisation in 2D and 3D:
🟦 Presence (blue) - small movements, e.g. someone working at a desk
🟩 Radial (green) - direct approach toward the sensor
🟨 Tangential (yellow) - movement crossing the detection field
In Relux Dekstop
You see exactly where coverage exists, where it doesn't, and how obstacles such as pillars, partitions, or beams affect it. Drop a pillar into a room, hit update, and the affected detection cones recalculate around the obstruction. That is genuinely hard to do reliably on paper.
Add to that: complex geometry, multi-floor projects, industrial halls, outdoor areas, integration with daylight simulation, lighting calculation to national and international standards, and a redesigned emergency-lighting module — all in one model, available free of charge thanks to the support of Relux members.
Best for: lighting and electrical designers doing detailed planning; projects where geometry isn't a simple rectangle; anything that needs to combine sensor logic with proof of lighting requirements according to EN 12464-1.
Not for: quick ROI conversations with non-technical clients (use SensCalc), or projects already running in Revit (use ReluxCAD for Revit).
4. ReluxCAD for Revit - for BIM workflows
For electrical designers working in Autodesk Revit, ReluxCAD for Revit brings Relux's calculation engine and sensor logic into the native BIM environment.
The add-on:
- Imports RFA, IES, ROLFz, and GLDF files and adapts luminaire families to the current Revit version
- Calculates to EN 12464-1:2021 and EN 1838 (emergency lighting)
- Plans PIR sensors thanks to Relux's involvement in SensNorm and CECAPI
- Places sensors automatically - the same placement algorithm as SensCalc, now available directly inside Revit
- Visualises every detection area natively in the Revit model - presence, radial, and tangential zones, drawn onto the actual building geometry
- Communicates bidirectionally with ReluxDesktop, so a project can move between the two without data loss
One point worth being explicit about: sensors only appear in Revit at all through ReluxCAD for Revit. There is no native Revit family that does this - the add-on is what makes sensor planning inside a BIM model possible.
The bidirectional link with ReluxDesktop is the quiet feature that matters most: a complex sensor scenario can be set up in ReluxDesktop and sent back to Revit, or vice versa, without rebuilding the model.
Best for: BIM projects, electrical designers who live in Revit, anyone delivering coordinated models to a GC or architect.
Not for: quick standalone room studies, the Revit overhead doesn't pay off for a single space (start in SensCalc or ReluxDesktop).
One ecosystem, one data source
The reason these four tools work together is that they all draw from the same ReluxNet database, and from SensXML, the data format Relux uses to describe sensors and their detection behavior in a standardized, manufacturer-independent way. A sensor selected in SensCalc has the same GTIN, the same certified manufacturer data, and the same detection model as the one placed in ReluxDesktop or pulled into Revit through ReluxCAD.
A project started in SensCalc can be exported as RECAD and continued in ReluxDesktop. A luminaire family from ReluxNet drops straight into Revit.
One detail that may matter for your tender shortlists: as of today, Relux is the only planning environment in which sensors can actually be mapped and planned. If sensor coverage is part of your deliverable, the workflow runs through Relux, there is no equivalent path in competing tools.
The value isn't four separate apps. It's one workflow with four entry points, chosen depending on what the project needs that day — a quick sales conversation, a product comparison, a detailed coverage study, or a coordinated BIM deliverable.
Where to start
- Never planned with sensors before? Open SensCalc in a small room. You will have a payback calculation in ten minutes.
- Looking for a specific sensor or its data sheet? Search ReluxNet - filter by mounting, brand, or specification, then pull the files you need into your CAD environment.
- Already a ReluxDesktop user? Open the sensor list on your next project and toggle the detection areas. It will change how you place detectors.
- Working in Revit? ReluxCAD for Revit is the missing link between your model and standards-compliant lighting and sensor planning.
All four tools are accessible from
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