User Manual

Application Note #480
21 Technical Support — 800.523.9466
®
Ambient Light Detection (ALD)
How it Works
ALD allows you to maximize the cost savings of lighting
by keeping lights OFF when the natural light in a space
provides adequate lighting.
The Lutron® ALD feature learns your preference as you
live with the product in your space. The learning algorithm
employs user input to determine when ambient light is not
adequate.
Will my Maestro® Sensor Dimmer use ALD?
Your Maestro® Sensor Dimmer will use ALD if you’ve
selected Ambient Light Detect (ALD) mode while
programming your unit. Some Lutron® in-wall sensor
models allow you to change the Auto‑ON settings
independently of ALD. In those models, you must have
both ALD and Auto‑ON/Auto‑OFF (Occupancy mode)
enabled. Dual Tech sensor models offer two ALD modes:
Learning ALD and Fixed ALD; the Learning ALD mode
matches the ALD modes used in all other Lutron® in-wall
PIR sensors. Refer to the instruction sheet for your product
to determine how to activate and use ALD.
How does the Maestro® Sensor Dimmer learn my
preference?
Whenever you enter a room with a Lutron® in-wall sensor
using the Learning ALD feature, the sensor will either turn
the lights ON or keep the lights OFF, based on its current
light-level threshold set in ALD mode. If you enter the
room and the lights do not respond as you’d like, press
the
T
button on your Maestro® Sensor Dimmer to turn
the lights ON (or OFF, if that was your preference) within
5 seconds of entering the room. The Maestro® Sensor
Dimmer has now learned a new light threshold for ALD.
The example below illustrates the learning process:
1. You enter the room, the lights stay OFF, and you decide
that you want the lights ON because there is not enough
ambient light in the space for you.
2. You press the
T
button (within 5 seconds of entering
room).
3. The Maestro® Sensor Dimmer has now learned your
preference for when lights should turn ON, and adjusted its
threshold accordingly.
FAQs
If I press a button AFTER 5 seconds of entering a room,
will my Maestro® Sensor Dimmer learn that preference?
No, you must interact within the first 5 seconds of entering
the room.
How many times will I have to interact with the Maestro®
Sensor Dimmer until it remembers my settings?
Typically, the Maestro® Sensor Dimmer learns the
appropriate threshold within 6 –10 interactions or less.
Do you offer ALD and Off-While-Occupied (OWO)
Enabled together?
When ALD is selected in your Maestro® Sensor Dimmer,
OWO is enabled as well. In order for the ALD to respond
correctly to the user’s preference, it will always maintain the
light level in the room for as long as the space is occupied,
whether that light level is ON or OFF.
I believe I’m using ALD correctly in my Maestro® Sensor
Dimmer, but I’m still not getting the response I expect.
What could be happening?
– You may have multiple users with widely different
preferences. If multiple users continue to teach the unit
separate preferences, it will continue to adjust to meet
the threshold, but may be stuck somewhere in between
the preferences of the two users.
– You may be trying to apply this feature to an application
that is not exposed to daylight. This feature is designed
to respond to natural light; it will not necessarily respond
with the same sensitivity to synthetic light sources that
operate on different wavelengths.
– You may not be able to reach your unit within
5seconds. If your interactions do not occur within
5seconds, you may not be teaching the unit a new
threshold.
Note: Make sure that you interact with the Maestro®
Sensor Dimmer within 5seconds of entering the room, if
you intend to teach it to turn ON. If multiple users interact
with the unit on a regular basis, and have different light
preferences, the unit may be trying to learn two separate
preferences. Ensure that ALL users are educated in how
ALD works when ALD is selected.
Will the Maestro® Sensor Dimmer actively adjust the
light level to maintain a certain level of brightness in the
room?
No, the lights will turn on to whatever level has been set as
your Occupied Level. ALD allows the unit to determine only
when light is needed; it does not determine how much light
you want.