MS-HS3 Humidity Sensor Switch
Specifications:
- Model: MS-HS3
- Product: Humidity Sensor Switch
- Power Input: 120 V~ 50 / 60 Hz
- Maximum Load: 3 A
- Application: English Fan
Product Usage Instructions:
Installation:
- Turn power OFF at the circuit breaker to avoid shock
hazards. - Ensure a neutral or ground connection is present in the
electrical box. - Remove the existing device and connect the humidity sensor
switch following the provided guidelines based on neutral
availability. - Mount the switch securely using the provided screws.
- Turn power ON at the circuit breaker and allow the device to
power up fully (up to 20 seconds).
Operation:
After full power up, use the main toggle button to change the
load state and test the installation. Note that humidity sensing
will activate after a button press to turn off the fan, with a
default timeout of 30 minutes.
FAQ:
Q: Can the humidity sensor switch be used in multi-location
circuits?
A: No, the humidity sensor switch is designed for single-pole
locations only and should not be used in 3-way or multi-location
circuits.
Q: What should I do if I don’t have a neutral or ground
connection in my electrical box?
A: If no neutral is present, connect the green-sleeved wire to
ground. If neither wire is present, it is recommended to consult an
electrician for proper installation.
Q: How can I test if the humidity sensor switch is functioning
correctly?
A: After installation, restore power and observe the LED status
indicator. Press the main toggle button to test changing the load
state. Allow the default timeout of 30 minutes after turning off
the fan to activate humidity sensing.
MS-HS3
Humidity Sensor Switch
120 V~ 50 / 60 Hz
English Fan 3 A
Introduction
The humidity sensor switch controls exhaust and vent fans to remove moisture in the space when humidity levels exceed the threshold. The humidity sensor switch is ideal for bathrooms as it can detect rapid increases in humidity from showers or baths to reduce mold and mildew. It will also detect gradual increases in humidity in bathrooms as well as utility rooms, basements, and other spaces.
Important Notes
1. CAUTION: To reduce the risk of overheating and possible damage to other equipment, DO NOT use to control receptacles. 2. Install in accordance with all national and local electrical codes. 3. A neutral or ground connection is required for the product to function. When a neutral connection is available, remove the green sleeve and connect to the
neutral. If a neutral is not available, connect the green-sleeved wire to ground only in retrofit and replacement applications. If neither wire is present, consult a licensed electrician. 4. For indoor / dry location use only. Operate between 32 °F and 104 °F (0 °C and 40 °C). 5. Clean with a soft damp cloth only. DO NOT use any chemical cleaners. 6. DO NOT exceed twenty (20) devices on a single branch circuit. 7. Device makes an audible click when turning on / off. This is normal functionality. 8. Do not use for ceiling paddle fans. 9. For supply connections use 18 AWG (1.0 mm2) or larger wires suitable for at least 167 °F (75 °C).
WARNING: ENTRAPMENT HAZARD. To avoid the risk of entrapment, serious injury, or death, these controls must not be used to control equipment that is not visible from every control location or that could create hazardous situations if operated accidentally or through malfunction (for example, motorized gates, garage doors, industrial doors, microwave ovens, heating pads, fireplaces, space heaters, etc.). It is the installer’s responsibility to ensure that these controls are connected only to suitable loads and equipment types and that such equipment is visible from every control location. Failure to do so could result in serious injury or death.
1 Turn power OFF at the circuit breaker
WARNING: SHOCK HAZARD. May result in serious injury or death. Turn off power at circuit breaker or fuse before installing.
ON OFF
2 Ensure a neutral or ground connection is present
Look for a bundle of white neutral wires coming out of the electrical box. A. When a neutral is present, remove the green sleeve and connect the white wire to neutral from the electrical box. Connect the bare wire from the device to
the ground wire from the electrical box. B. If no neutral is present, connect the bare and green-sleeved wire from the device to the ground wire from the electrical box (can only be used in retrofit and
replacement applications when neutral is not available). C. If neither wire is present, consult an electrician. This device will not function if it is not connected to neutral or ground.
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MS-HS3
3 Remove the existing device and connect the humidity sensor switch
Note: The humidity sensor switch is for single-pole locations only. Not for use in 3-way or multi-location circuits.
A. If neutral IS present in the electrical box: Remove green sleeve, connect white wire to neutral.
B. If neutral IS NOT present in the electrical box: Connect the green-sleeved wire to ground.
Black
Black
Black
Bare wire
Insert and twist to tighten
Ground wire (bare or green) REQUIRED
White wire (green sleeve removed)
Neutral white wire(s)
Notes: · Wire colors in the electrical box may vary. · The black wires coming out of the humidity sensor switch are
interchangeable.
4 Mount the switch using the provided screws
Black
Bare wire Green-sleeved wire
Insert and twist to tighten
Ground wire (bare or green) REQUIRED
Note: The black wires coming out of the humidity sensor switch are interchangeable.
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ON OFF
5 Turn power ON at circuit breaker
MS-HS3
Once the power has been restored the status LED will blink until the device is fully powered up, which may take up to 20 seconds. Pressing the main toggle button during this time will not change the load state and the LED will continue to blink to indicate the powering up is still in progress.
After power has been restored and the device has fully powered up, the main toggle button can be used to change the state of the load and to test the installation.
Note: Humidity sensing will not be operational until the timeout has expired after a button press to turn off the fan. The default timeout is 30 minutes.
Status LED
6 NAdEdWitiToInTaLlEmNoEdEeDsEaDnd settings
The default factory settings have been optimized to meet the expectations of most customers for standard bathrooms and damp spaces (e.g., utility rooms and basements). However, the humidity sensor switch has several adjustable settings that can be used to alter operation for user preference or when necessary to address specific issues to accommodate non-standard space configurations. Air Cycle Mode This mode is used to circulate stale, stagnant air in spaces such as basements with poor ventilation. The fan will turn on every hour and run for the duration determined by the timeout setting. To enable Air Cycle Mode, go to www.lutron.com/MS-HS3/air_cycle
7 Installation is complete!
Lutron recommends adding the support QR code label (provided in box) to the back of the wallplate prior to fully installing it over the humidity sensor switch. If changes are needed after living with the humidity sensor switch for a few days, adjustments can be made by scanning the QR code or by going to www.lutron.com/MS-HS3 to get detailed instructions on how to make changes to the settings by using Advanced Programming Mode (APM).
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8 Operation
MS-HS3
General Operation
The humidity sensor switch measures humidity levels in the space and uses advanced signal processing to determine when to activate the fan. The default operating mode will detect shower activity and / or high humidity levels, at which point the controlled fan will turn on. The fan will then run until the user-selectable timeout has expired (the default setting is 30 minutes). When the fan is running, the white status LED will be bright. Once the timeout has expired, the white status LED will transition to “dim”.
For most bathrooms, the fan will turn on during the shower or slightly after the shower has ended and the user has opened the shower enclosure. Typical propagation of humid air will fill the room starting at the ceiling and then move down the walls. This means that it is not uncommon for the mirror to begin fogging before the control senses that the humidity has changed and turns on the fan.
Operation
Main Toggle Button: · Tap On: Fan runs for the set timeout period · Tap Off: Humidity sensing disabled and fan stays
off for the set timeout period
Humidity Sensing: · Detects excessive humidity, fan runs for the set
timeout period
User-Selectable Global Timeout Setting 1
(Default: 30 minutes)
30 minutes
Note: The ability of the humidity sensor switch to detect changes in humidity levels and how quickly the fan turns on can be impacted by many factors. Spaces with high ceilings, open floorplans, glass shower doors with small openings, or significant ventilation will delay the movement of humidity towards the control and delay when the fan turns on.
1 The default timeout period is 30 minutes. This is a global timeout that applies to any operation where timeout period is referenced. Timeouts and humidity sensing modes are programmable. For more information, go to www.lutron.com/MS-HS3
Override: On Tap twice quickly to turn on indefinitely
1 second
Override: Off Hold for 1 second to turn off indefinitely
Notes: · The status LED will cycle between 2 seconds bright and a
0.5 second dim. · Pressing the main toggle button once will return the unit to
normal operation.
Notes: · The status LED will cycle between 2 seconds dim and a
0.5 second bright. · Pressing the main toggle button once will return the unit to
normal operation.
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9 Troubleshooting
MS-HS3
For the best experience and to fully understand the humidity sensor switch’s operation in your unique space, Lutron recommends that you live with the device for a few days using the default settings prior to making any adjustments.
· Test the fan operation by manually pressing the toggle button. If the fan does not turn on, turn off power at the breaker and check the wiring. If the status LED turns bright when the button is pressed but the fan does not turn on, the fan may be faulty and may need to be replaced.
Note: Humidity sensing will not be operational until the timeout has expired after a button press to turn off the fan. The default timeout is 30 minutes.
· If the device is not operating as expected, please scan the QR code label on the humidity sensor switch or go to www.lutron.com/MS-HS3 to learn about helpful hints and tips to optimize the sensor switch for your space.
· If additional help is needed, please go to the Need Help section at www.lutron.com/MS-HS3
Limited Warranty: www.lutron.com/warranty or call 1.844.LUTRON1 for a printed copy. Lutron and any related trade dress and logos are trademarks or registered trademarks of Lutron Electronics Co., Inc., in the U.S. and other countries. All other product names, logos, and brands are property of their respective owners.
www.lutron.com/support
24 / 7 Support: 1.844.LUTRON1 (USA / Canada) +1.888.235.2910 (Mexico)
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Documents / Resources
 | LUTRON MS-HS3 Humidity Sensor Switch [pdf] Owner's Manual MS-HS3, MS-HS3 Humidity Sensor Switch, Humidity Sensor Switch, Sensor Switch, Switch |