User Guide

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Operation Instructions When more than 1 area is controlled by the GX™ 850 system, it is also possible to pri- oritize the areas. Prioritizing makes it possible to operate 2 areas, even if the required power for 2 areas is not present. The GX™ 850 is fully automatic and operated digitally by means of the intelligent sen- sors located in the heated terrain. Each sensor measures both temperature and mois- ture, and the system turns the heating elements on and off based on these readings. By combining moisture and temperature readings, the system is able to save around 75% energy compared to systems which only measure temperature readings. The digital sensors used for the GX™ 850 also provide the most exact readings when compared with corresponding analogue systems. The result is optimum functionality and low energy consumption. A typical installation consists of:
• Controller unit (only one)
This is the device which, based on the measure- ments from the sensors, decides when to heat the connected area(s).
• Power supply (one or more)
The power supply delivers power to the controller unit and the connected sensors.
• Ground sensor (one or more)
At least 1 ground sensor is needed for each ground area, but to get the best performance of a system, 2 or more sensors are recommended. For more information please refer to the sensor manual.
• Roof sensor (one or more)
At least 1 roof sensor is needed for each roof area, but for complex roof constructions, 2 or more sen- sors are recommended. For more information please refer to the sensor manual.
For more information about the ice and snow melting function of the GX™ 850, please refer to: Appendix B: “How it works”.
Operation Instructions
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Ground system The ground system is fully automated. It gathers information on moisture and temperature via digital sensors continuously. The sensors are placed on stra- tegic spots on the ground area (for further informa- tion on the sensor please refer to the sensor manual). By combining measurements of both moisture and temperature a reliable detection of the situation is achieved. Hence it is known whether heating is required to prevent ice and snow from covering the roof area. Standby The system is on standby awaiting need for heating. If the measured temperature is below the chosen standby temperature the system will automatically heat the area in order to maintain the standby temperature. Melting (heating) will start when the two following conditions are fulfi lled: • Measured moisture is higher than the chosen setpoint for moisture. • Measured temperature is lower than the chosen melting temperature Temperature and moisture are measured continuously by the sensors. Melting ice and snow As long as the measured temperature is lower than the chosen melting temperature heating of the ground area will be on. When the measured temperature reaches the chosen melting temperature and the measured moisture level is below the chosen limit, the post-heating function will be activated. The post-heating function can be disabled. If moisture is detected on the ground area the system will continue to heat the area in order to maintain the melting temperature. It is, however, important to understand that even when the system is melting ice and snow it is not necessarily heating at all times. The heating will be turned on and off in accordance with the measured tempera- ture in order to maintain a constant melting temperature. If the temperature rises more than 35°F (1.5°C) above the chosen melting temperature the system will automatically stop heating the area irrespective of the moisture on the area. Appendix B
Standby
(No heating)
Melting
(Heating)
Post-heating
(Heating)
Standby
Mantaining standby
temperature
(Heating)
Temperature < Melting temperature and Moisture > Moisture limit Moisture < Moisture limit
Temperature < Standby temperature Temperature >- Standby temperature
Poat-heat time elapsed
Temperature >
Melting
temperature + 1,5˚C