13.90 NA7.6.2.2 and 7.6.2.3 Occupant Sensor Acceptance

Use Form NRCA-LTI-02-A

Purpose of the Test

The purpose of the test is to ensure that occupant sensors are located, adjusted, and wired properly to achieve the desired lighting control. There are two basic technologies in three configurations utilized in most occupant sensors: 1) infrared; 2) ultrasonic (passive or active); and 3) a combination of infrared and ultrasonic.

Benefits of the Test

Occupant sensors are used to automatically turn lights ON immediately when a space is occupied, and automatically turn them OFF when the space is vacated after a pre-set time delay. Some sensors are configured so the user must manually switch the lights ON but the sensor will automatically switch the lights OFF (manual-ON controls). These are commonly called ‘vacancy sensors’ and are included in this testing procedure. Automated lighting controls prevent energy waste from unnecessarily lighting an unoccupied space.

Instrumentation

This test verifies the functionality of installed occupant sensors visually and does not require special instrumentation.

Test Conditions

Occupant sensors are installed properly and located in places that avoid obstructions and minimize false signals.

All luminaires are wired and powered.

During the test, the space remains unoccupied.

Document the initial conditions before overrides or manipulation of the BAS. All systems must be returned to normal at the end of the test.

Estimated Time to Complete

Construction Inspection: 0.25 to 0.5 hours (depending on visual and audible inspection requirements)

Equipment Test: 0.5 to 1 hours (depending on necessity to adjust time delay or mask sensor to prevent false triggers)

Acceptance Criteria

Standard occupant sensor responds to “typical” occupant movement to turn the lights ON immediately.

Manual ON occupant sensor requires occupant to switch lighting on.

Multi-level occupant sensors meet uniformity requirements; the first stage activates between 30-70 percent of the lighting power; after that event the occupant has the ability to manually activate the alternate set of lights, activate 100 percent of the lighting, and deactivate all of the lights.

Conditions where partial ON/OFF controls are required 'in 'addition to or instead of the basic controls requirements are identified and the controls properly reduce lighting power by at least 50 percent.

Ultrasonic occupant sensors do not emit audible sound.

Lights controlled by the occupant sensor turn OFF when the preset time delay is met.

The maximum time delay is not greater than 30 minutes.

Occupant sensor does not trigger a false ON or OFF.

Status indicator or annunciator operates correctly.

Potential Issues and Cautions

It is imperative that the test be performed during a time when the tester can have full control over the occupancy of the space.

The time delay can be adjusted to minimize test time, but the time delay setting must be reset upon completion of the test (not to exceed 30 minutes).

Plan sensor location to avoid detection of significant air movement from an HVAC diffuser or other source, which can cause the sensor to turn the lights ON (this is most critical with ultrasonic sensors).

Avoid detection of motion in adjacent areas and unwanted triggers by adjusting coverage pattern intensity or masking the sensor with an opaque material.

Educating the owner about furniture and partition placement in the spaces can avoid future problems with infrared sensor performance (which rely on “line-of-sight” coverage).

The purpose of the test is to ensure that an occupant sensor is located, adjusted, and wired properly to achieve the desired lighting control. Occupant sensors are used to automatically turn lights on and keep them on when a space is occupied, and turn them off automatically when the space is unoccupied after a reasonable time delay. The time delay, typically adjustable, will prevent lights from rapid cycling through ON and OFF when spaces are occupied and unoccupied frequently. It also helps avoid false OFF triggering when there is little apparent occupant movement. There are two basic technologies in three configurations utilized in most occupant sensors: 1) infrared; 2) ultrasonic (passive or active); and 3) a combination of infrared and ultrasonic detection.

Ultrasonic sensors should not emit audible sound. As the name implies, ultrasonic sensors emit ultrasonic sound waves at frequencies that should be imperceptible to the human ear. Ensure the sensor does not emit any sounds that ARE audible to the human ear at typical occupant location.

Ensure that occupant sensors have been certified to the Energy Commission in accordance with the applicable provision in §110.9. Verify that model numbers of all occupant sensors are listed on the Energy Commission database as “Certified Appliances & Control Devices.”

Ensure the space being tested remains unoccupied during the test and wait for the lights to turn off (sensor delay time can be adjusted to shorten test time).

• Lights controlled by the occupant sensor turn off when the time delay is met. If the time delay was not adjusted prior to the test, ensure the maximum delay is not greater than 30 minutes. If the time delay was adjusted to minimize test time, ensure the sensor time delay setting does not exceed 30 minutes.

• Occupant sensor does not trigger a false ON. Ensure that any movement outside the desired control zone does not activate the lights. Examples include:

• Walking in an adjacent zone close to the control zone, (consider that designers sometimes employ overlapping sensor coverage areas as part of the design)

• Movement other than occupants (i.e. air flow from HVAC system or furnishing movement due to external forces)

Step 2: For a representative sample of building spaces, simulate an occupied condition.

• Most occupant sensors have an LED that will illuminate (typically flash) when motion is detected, where others may emit an audible sound.

Except if the sensor has “manual-ON” capability. The occupant sensors that are required to have “manual-ON” capability are identified on the Lighting Control Worksheet.

• Occupant sensor does not trigger a false ON. Ensure that any movement outside the desired control zone does not activate the lights. Examples include:

o Walking in an adjacent zone close to the control zone, (consider that designers sometimes employ overlapping sensor coverage areas as part of the design, so ensure that the zone coverage test has a reasonable demarcation)

o Movement other than occupants (i.e. air flow from HVAC system or furnishing movement due to external forces)

• In the partial off state, lighting shall consume no more than 50% of installed lighting power, or:

o No more than 60% of installed lighting power for metal halide or high pressure sodium lighting in warehouses.

o No more than 60% of installed lighting power for corridors and stairwells in which the installed lighting power is 80 percent or less of the value allowed under the Area Category Method.

• Light level may be used as a proxy for lighting power when measurements are taken.

• The occupant sensing controls turn lights fully ON in each separately controlled areas, Immediately upon an occupied condition

Simulate a situation where an occupant enters a space with a partial on sensor arrangement.

• The occupant sensor will activate the first stage of lighting, between 30 to 70% of the total lighting connected load for the specific lighting equipment controlled.

• After the first stage occurs, manual switches are provided to activate and deactivate the alternate set of lights, bringing the total power consumption up to the full connected load of the controlled lighting equipment.

• Both stages of lighting (automatic and manual stages) turn OFF with a maximum of 30 minute delay from the beginning of the unoccupied condition.

• Occupant sensor does not trigger a false ON. Ensure that any movement outside the desired control zone or HVAC operation does not activate the lights.

Part 4: Occupant Sensor Serving Small Zones In Large Open Office Plan For Power Adjustment Factor (PAF)

For each controlled zone that is being tested, first complete Functional Test 2 (Occupant Sensor) to confirm that the sensor is switching the lights on and off as required. Then enter the information described below:

Write in the size of the controlled zone, which is to say the zone underneath the lighting controlled by this occupant sensor. The boundaries of the controlled zone should lie halfway between one light fixture and the next, if the light fixtures are on a regular grid.

From line (a) on the test form, enter the power adjustment factor that corresponds to the size of the controlled zone (<125sf for PAF=0.4, 126-250sf for PAF=0.3, 251-500sf for PAF=0.2).

• Enter PAF claimed for occupant sensor control in this space from compliance documentation

Simply enter the PAF for this controlled zone, from the Certificate of Compliance

• The PAF corresponding to the controlled area (line b), is less than or equal to the PAF claimed in the compliance documentation (line c)

This step is to ensure that the PAF being claimed in the acceptance test is not more than the PAF that was claimed for the same zone on the compliance form.

• Sensors shall not trigger in response to movement in adjacent walkways or workspaces.

The sensor switches on the lights only in response to movement within the group of workspace(s) that together constitute the controlled area. The lights must not trigger in response to movement in nearby areas.

• All steps are conducted in Functional Test II “Occupancy Sensor (On Off Control)” and all answers are Yes (Y)

This step verifies that Functional Test 2 has been conducted, to verify that the occupant sensor switches the lights between their high and low states as required.