SE Controls Stand Alone Rain Sensor Manual

Stand Alone Rain Sensor
Technical Information and Operating Instructions
Introduction.
The stand alone rain sensor automatically detects
rain or snow fall and signals the ventilation
control system to close open vents.
The sensor is built into a plastic weatherproof
enclosure. The mounting bracket system has
been designed such that the sensor can be
mounted on to any suitable external façade of a
building and adjusted for optimum rain
detection.
For correct operation, the sensor requires a
24VAC/DC ± 20% power supply @ 55mA to power
the electronics and heater element. The signaling
to the ventilation control system is via volt free
contacts rated at 30VDC @ 1A resistive. The
sensor is NOT suitable for operation at 230VAC.

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Important Notice
• This equipment is intended for permanent connection and does not have an on/off switch.
• Do NOT adjust or alter the device or its enclosure (including labelling/marking).
• Do NOT use the device for any other purpose other than that intended by SE Controls.
• Do NOT allow installation of the device by unqualified persons.
• Failure to install the device in accordance with the manufacturer’s instructions will invalidate any
warranties.
• Unless otherwise indicated, you must not adjust or remove existing manufacturers cabling or use
terminal outputs or inputs for purposes other than their design without written authorisation from SE
Controls.
SE Controls accepts no liability for failure to comply with the above statements or the installation and
operation guidance in the following sections of this guide and reserves the right to invalidate the
warranty of the controller.

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Installation
2. Installation
2.1 Packaging
The stand alone rain sensor assembly comes supplied in a polythene bag.
2.2 Mounting location
The stand alone rain sensor should be mounted on an external façade of the building. It must be mounted
in a location that is easily subjected to rainfall.
2.3 Fixing
Loosen the two bracket adjustment lock screws and fold the bracket up toward the body of the sensor.
Offer the sensor up to the mounting surface with the sensor contacts facing upward. Mark through the
three fixing holes with a marker pen and place the sensor to one side. Drill appropriately sized pilot/fixing
holes and use suitable plastic plugs where appropriate. Note that it is recommended that 30mm No6 pan
head screws are used to secure the body in place. These should preferably be brass or steel that has been
treated for external use (e.g. black japanned). Fix the sensor bracket to the wall using three fixing screws.
Adjust the sensor body so that incident rain will readily run of the sensor’s face and lock up the two bracket
adjustment lock screws.
2.4 Connection details
2.4.1 Preamble
The stand alone rain sensor leaves the factory with all fixings pre-sealed to prevent water ingress. Should it
become necessary to open the enclosure during the installation/configuration process, then it is important
that this sealant is replaced using a suitable silicon-based sealant upon completion of the commissioning
process.

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2.4.2 Standard factory configuration
The stand alone rain sensor is supplied from the factory pre-terminated with 3M of 4 core cable. These
factory selected configurations and settings should be adequate for most installations.
Colour
Signal
Connect To
Red
VA
24VDC/24VAC
Black
VB
0VDC/24VAC
Blue
CM
Volt Free Signal
Connected together when rain is detected.
Yellow NO Volt Free Signal
Alternate Configurations.
•In the unlikely event that an alternate configuration is required, then the following information
should be made reference to:

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Main PCB Connection Detail.
2.5 Sensitivity Adjustment
The sensitivity of the rain sensor has been pre-set at the factory and does not normally require further
adjustment.
Notes.
SE Controls
Lancaster House,
Wellington Crescent,
Fradley Park,
Lichfield,
Staffs. WS13 8RZ
Tel [phone]
www.secontrols.com
Signal
Detail
NO
Normally open contact
Volt free changeover relay
CM
Common contact
NC
Normally closed contact
VA
24VDC connection
Also suitable for 24VDC power if
desired
VB
0VDC connection
HT
Heater enable link
Link together to enable the
heater circuirty
HT Heater enable link