PIR Detector Performance Testing

Fresnel Factory measures how far, how wide and how strongly a PIR detector actually senses a moving human target — using an automated 5-axis CNC test system and a temperature-controlled scaled dummy, instead of a person walking across a room.

Which PIR test do you need?

Pick by the stage you are at: SPT-A tunes a new module, SPT-R and SPT-S verify a finished product against a standard, SPT-F verifies an animal-immunity claim, and DCM watches for drift once you are in production.

Why does an assembled PIR detector need to be measured?

Because detection range and detection area are not properties of the sensor alone. They are produced by the lens, the sensor position, the enclosure, the electronic circuit and the sensitivity settings acting together.

A PIR sensor element by itself cannot form a defined detection direction or detection area. The Fresnel lens does two things: it concentrates infrared energy from a chosen direction onto the sensor element, extending detection distance, and it divides the space in front of the detector into detection and non-detection zones. When a person crosses from a non-detection zone into a detection zone, the incident infrared energy changes and the detector produces a signal.

That means the same sensor element, behind two different lenses, gives two different products. And the lens itself does not always behave as designed:

• Optical design — the position, angle and focal characteristics of each lens segment decide where detection zones land. Differences show up more clearly at the periphery than at the centre.
• Lens material — internal infrared transmittance varies with material, colour, additives and thickness, changing how much energy reaches the sensor.
• Mold manufacturing — Fresnel lenses need smooth optical surfaces, so mold machining quality feeds directly into sensing performance.

Why an automated test instead of a walk test

IEC 63180 and EN 50131-2-2 both specify test conditions for motion detector evaluation, including movement speed and travel distance. Running those conditions with a real person requires a large test space and a long measurement time, and differences in walking speed and gait between operators change the result. Two runs are not comparable.

Automated measurement replaces the person with a movable dummy that simulates a human target. Heaters in the head, torso and leg sections hold defined temperatures representative of a human body. The detector is fixed at a specified position and height, the dummy is driven at a specified speed, and the system records detection position together with the sensor output signal. The result is stable conditions, reproducible data and far less measurement time.

SPT-A — Angular Signal Profile

Module signal measurement and threshold tuning support Tune

SPT-A records the actual signal your sensor module receives, at several angles across the field of view, so that threshold and delay time can be set from measured data instead of from trial and error in the field.

The detector is measured as a complete module — lens, the sensor you have selected, the circuit and the enclosure together. The dummy is driven at a specified speed and the sensor output is recorded continuously as relative signal strength against movement time, repeated at several field-of-view angles. What comes back is the shape of the signal, not a pass or fail verdict.

Standard angle set — 14 angles

A standard SPT-A engagement measures 14 angles, in one of two ways:

• a 140° sector swept in 10° steps, or
• 14 angles you specify, distributed across the full field of view of the device under test.

The second option suits detectors whose field of view is wider or narrower than 140°, or where you already know which zones matter. Additional angles beyond 14 are quoted separately.

What you receive

• Signal waveform for each of the measured angles
• Peak values, and centre-zone versus edge-zone comparison
• The observed margin between motion signal and background
• Reference data for evaluating Threshold and Delay Time settings

SPT-A needs signal strength, not just an ON/OFF output. The whole point of this test is the shape and amplitude of the signal, so a dry contact that only says “detected” is not enough. An analog test point ahead of the comparator is the usual way to provide it — but it does not have to be analog. Any output that lets us read signal strength per angle works, including a digital or serial output that reports the sensor level. Tell us what your module can expose and we will confirm before quoting. See what you need to send.

Where it helps

• Setting Threshold and Delay Time against the real movement speeds your product must catch
• Finding where in the field of view your noise margin is thinnest
• Comparing two lens candidates against the same sensor, under identical conditions
• Checking that a detection zone actually produces the sensor signal it was designed to produce

Signal-strength data is supplied as measured reference data for your own evaluation. We report what the module produced under the stated conditions; the final Threshold and Delay Time decision stays with your engineering team.

SPT-R — Detection Range Report (IEC 63180)

Detection distance and detection area to IEC 63180 Verify

SPT-R measures where a moving target is detected and plots the result as a detection map, following the test conditions defined in IEC 63180.

IEC 63180 — Methods of measurement and declaration of the detection range of detectors — Passive infrared detectors for major and minor motion detection — was published by the International Electrotechnical Commission in June 2020. It allows a scaled test dummy for automated testing at different mounting heights, which is what makes a 45 m detection diameter measurable indoors.

Tests performed

Test	Method
Radial motion	The target starts as far from the detector as the setup allows and moves toward it until detection occurs; the detection range is recorded. The table then rotates 10° and the measurement repeats until the full detection area is covered.
Tangential motion (major motion)	Grid cells of 1 m square as defined in the standard (0.2 m square at 1:5 scale).
Tangential small movement	Small-movement detection within the detection area.
Detection boundary	Tangential dummy movement with rotation angle −5° to +5° as defined in the standard.

What you receive

• A test report stating the device under test, test procedure, setup and conditions
• A plot for each test — radial, boundary and tangential small movement
• A comprehensive combined detection map
• Idealised detection areas expressed as diameters, ready for a declaration of detection range

Test conditions can be scaled to your product. A recent report, for example, covered a detector at a 4.6 m (15 ft) installation height with a 44 m (145 ft) maximum range and a 1 m/s target speed, measured at a 5:1 scale ratio.

SPT-S — Security Detector Evaluation (EN 50131-2-2 based)

Movement-condition testing for intrusion detectors Verify

SPT-S runs an intrusion detector through the movement speeds and travel distances defined in EN 50131-2-2 and returns a grid-based map of where the detector responded and where it did not.

EN 50131-2-2 is the part of the EN 50131 series that covers passive infrared detectors for intrusion and hold-up alarm systems. The sibling parts cover other detection technologies — EN 50131-2-3 for microwave, EN 50131-2-4 for combined PIR and microwave, and so on. Our testing is for PIR, so EN 50131-2-2 is the relevant part.

Security grades 1 to 4

EN 50131-2-2 provides for security grades 1 to 4 and environmental classes I to IV. The grade changes the requirements — target speeds, detection coverage and feature set all tighten as the grade rises, and Grade 3 and above add anti-mask requirements.

We are not limited to any single grade. The test conditions are configured to the grade you are targeting. The SPT machine drives the target from very low speeds up to 25 km/h, which covers the movement-speed requirements of every grade in the standard, and the grid resolution and measurement area are set per test rather than fixed.

Grade 2 and above normally require testing in an independent laboratory, which is slow and expensive to repeat. SPT-S is designed to be run before that: a fast engineering evaluation that finds the failure while it is still cheap to fix.

Example scenario set

The scenarios below are an example configuration from a customer project, not a fixed menu. Speeds, areas and travel distances are set to the grade and installation condition being evaluated.

Scenario	Target speed	Measurement area	Travel distance
Human detection on the field-of-view boundary	1 m/s	Customer-specified boundary	3 m
Human detection within the boundary	0.5 m/s	22.5 m × 40 m	3 m
Human detection within the boundary, high velocity	2 m/s	22.5 m × 40 m	3 m
Human detection close in	0.5 m/s	2 m × 3 m	3 m

What you receive

• A grid map of detection and non-detection points across the specified boundary
• The same map across the full measurable field
• Close-in and high-velocity response results
• Consistency of response across repeated runs

This is an engineering evaluation, not a certification. An EN 50131-2-2 based test performed here must not be described as product certification. Formal certification has to be carried out separately under the required certification procedure, by a body entitled to issue it.

What you receive — a look at the actual report

Every test returns a written report with the test conditions stated, a plot for each test performed, and a combined result you can act on. Below are pages from a real IEC 63180 report, with the customer's identifying details removed.

What a test report contains

• Device under test — what was tested, in what configuration, with which lens and settings
• Test procedure — which standard clauses were followed, and any agreed deviation stated explicitly
• Test setup and conditions — scale ratio, installation height, maximum range, target speed, test sequence, ambient temperature and humidity
• Results — a separate plot for each test performed
• Comprehensive data — the combined detection map
• Test summary — the measured result stated in plain numbers, such as idealised detection areas expressed as diameters

Reports are delivered as PDF. Underlying measurement data can be supplied on request in a tabular format for your own analysis.

False-alarm immunity and production monitoring

Two further services sit outside the development-project group above, because they answer different questions for different people.

SPT-F — False-Alarm Immunity Test Verify

Most PIR datasheets carry a pet-immunity figure — 20 kg, 85 lb, 80 cm height. Very few are backed by measured data, because a live animal will not repeat a defined path at a defined speed.

SPT-F uses temperature-controlled animal dummies on the same CNC stage to measure the ratio between the human signal and the animal signal at the same position: your discrimination margin. Indoor and outdoor products both apply, because the specification is written in mass and height, not species.

Pet and wildlife immunity testing →

DCM — Detection Conformance Monitoring Monitor

Approval-day performance is not guaranteed to survive two years of production. Mold wear, resin lot changes, supplier changes and production-condition drift all move a Fresnel lens, and nothing in the industry routinely checks it.

DCM is an annual programme that re-measures your product every quarter and compares it against its approved baseline. Your detector does not have to be one we designed.

Quarterly conformance monitoring →

Test system specification

The Scaled Performance Test (SPT) machine is a 5-axis CNC automated test system that measures a motion detector through a full 360° circle in a single measurement cycle.

Scaled test dummy

Testing at different mounting heights uses a scaled test dummy, which IEC 63180 permits for automated testing. A 1:5 scaled dummy is acceptable with the head held at 14 K above ambient temperature and the body and legs at 7 K above the ambient temperature of the test room. Head, torso and leg sections are numerically temperature controlled, and the whole assembly is driven by the CNC positioner rather than carried by an operator.

Mounting and fixtures

Devices under test are held in 3D-printed holders made for the specific product, and can be measured in wall-mounted or ceiling-mounted configurations. Custom measurement conditions — mounting height, tilt, target speed, grid resolution, angular step — can be set to match your product rather than the other way round.

How a test project runs

1. Tell us the product and the question. Detector type, mounting height and tilt, intended detection distance and area, and which of the services above fits.
2. We confirm test conditions. Scale ratio, target speed, grid resolution, angular step, mounting configuration, ambient conditions. Anything non-standard is agreed in writing before we start.
3. You send the device under test. A complete, assembled detector is preferred, because the measurement is of the whole system. Send the sensitivity settings you want measured.
4. We measure. Automated run on the SPT machine under the agreed conditions.
5. You receive the report — typically 2 to 4 weeks from receipt of samples.

Where testing fits in a lens development programme

If we are also designing your lens, performance evaluation is an optional step in the standard development process: customer request review → NRE quotation → optical design → customer design approval → mold fabrication → sample supply → performance evaluation → customer sample approval → mass production preparation → mass production. If we are not, that changes nothing about the test — we measure detectors regardless of who designed the optics.

What you need to send

Send complete, working detectors with power and signal wiring already attached, plus the mechanical and setting information we need to hold and configure them. The one requirement people miss is that SPT-A needs access to signal strength, not just the ON/OFF output.

SPT-R, SPT-S and SPT-F can be run from the normal ON/OFF detection output, because those tests record where detection occurred. The signal-strength requirement applies to SPT-A, and to the discrimination-margin part of SPT-F.

Pricing and what is included

Prices below are list prices for one product configuration, and include setup, the measurement itself and the written report.

Quoted separately

So there are no surprises in the invoice, the following sit outside the list price and are quoted before work starts:

• Measurement angles beyond the standard 14 (SPT-A)
• Additional settings configurations — for example the same detector measured at two threshold settings
• Additional devices under test beyond the units needed for the standard run
• Additional mounting configurations, such as measuring the same product wall-mounted and ceiling-mounted
• Non-standard test conditions — custom grid resolution, custom angular steps, speeds or areas outside the standard set
• Scenarios added beyond the four in SPT-S
• Expedited turnaround ahead of the normal 2 to 4 weeks
• Return shipping, where samples are to be sent back

Bundled pricing is available when several services run on the same device in one session, and when testing is attached to a lens development project with us. Ask for a written scope with the quotation — we will state the angles, configurations and mounting conditions the price covers.

Frequently asked questions