Installation Overview

The main function of the Weather Alarm is to alert a greenhouse controller that the weather conditions require the roof vent to be closed. The Weather Alarm can also report to the Bartlett Instrument Company Computer Interface System (CIS) program for weather monitoring and control. This installation manual will cover the general installation of the Weather Alarm and the specific connections to the Bartlett Instrument Company RWL Natural Ventilation Controllers and GHK Greenhouse Environmental Controllers.

A typical installation consists of Weather Alarm WR, plug-in transformer, sensor junction box, anemometer and rain sensor. Optional temperature and humidity sensors can also be connected to the Weather Alarm WR.

BE SURE ALL POWER IS OFF BEFORE INSTALLATION!
 

BE SURE ALL WIRING AND EQUIPMENT IS INSTALLED ACCORDING TO LOCAL ELECTRICAL CODES.

THE WEATHER ALARM WR IS A LOW VOLTAGE DEVICE. LIMITED TO 24V AC CONTROL VOLTAGES.

CAUTION:  The Weather Alarm WR is designed to be reliable but as with all equipment, failures do occur. Therefore, in situations where loss could result from the failure of the Weather Alarm WR, separate backup thermostat or alarm systems should be provided.

The reliability and performance of the Weather Alarm WR can be compromised by locating the controller in direct sunlight or in direct water spray.

Placement and Mounting

Mount the Weather Alarm WR in an easily accessible location. Usually close to the RWL Natural Ventilation Controller or GHK Greenhouse Environmental Controller. Protect the Weather Alarm WR from direct sunlight for better reliability and readability. Moisture can cause corrosion and premature failure, so avoid direct water and have all wires enter and leave through liquid-tight connectors, waterproof conduit, or seal the wires with silicone sealant.

WARNING: Some sealants release acetic acid while curing. Be sure sealant is completely cured (up to 3 days) before closing control box to avoid corrosion damage.

To mount the Weather Alarm WR, remove the front cover and unplug ribbon cable from the relay board. Insert the 4 self-drilling screws provided with the Weather Alarm WR through the 4 screw-hole knockouts and fasten the box to the wall. Cover the screw heads with plastic cups provided. After all wiring is complete and any sealant cured, reattach the ribbon cable and screw on the front cover.

Alternately, the Weather Alarm WR may be mounted with drywall screws placed through the corner holes of the box.
 
 

Rain Sensor

The rain sensor detects moisture on the surface of the sensor. It does not measure the amount of moisture that has fallen. The Weather Alarm WR junction box has one rain sensor input labeled RS. When the Weather Alarm WR detects moisture on the rain sensor the Weather Alarm WR turns on a rain sensor heater to quickly dry off the surface of the rain sensor after the rain has stopped. The Weather Alarm WR junction box has one rain sensor heater input labeled RSH.

To ensure proper readings, the rain sensor should be mounted in a location that will not be sheltered from rain from any direction. Mount the sensor at a 10 degree angle to keep water from pooling on the sensor surface. Also, the sensor should be mounted in an easily accessible location in order to clean any debris from the sensor surface.

The rain sensor comes with 6’ leads to connect the rain sensor and 6’ leads to connect the rain sensor heater to the four terminals of the junction box. The white/black twisted pair connect to rain sensor. The red/black twisted pair connect to the rain sensor heater.

Anemometer
For anemometer mounting instructions please refer to WS-201-01B manual.

Temperature Sensor

The optional thermistor is the temperature sensor. The Weather Alarm WR junction box has one thermistor input labeled TH.

To ensure proper readings, the thermistor should not be in direct sunlight or where it will be sprayed with water.

The thermistors come with 24’ leads and can be connected directly to the two terminals labeled TH. There is no special orientation to the thermistor leads.

Humidity Sensor

The optional humidity sensor should be mounted in any location that it is necessary to measure humidity levels. The Weather Alarm WR junction box has terminals marked Hum In, Hum Power and Hum GND.

To ensure proper readings, the humidity sensor should not be in direct sunlight or where it will be sprayed with water.

Weather Alarm WR Outputs

The Weather Alarm has three alarm outputs – wind alarm, rain alarm, and wind or rain alarm. The wind and rain outputs activate separately based on individual sensors. The “wind or rain” output activates when either sensor exceeds its set point.

The wind alarm, rain alarm and wind or rain alarm are dry contacts to directly connect to a RWL Natural Ventilation Controller or GHK Greenhouse Environmental Controller. It is possible to source 24 V AC to drive a relay by using a jumper wire to connect terminal 1 to terminal 22 – see diagram Connecting Multiple Controllers, Isolated.

Connection Locations