Fire Protection System
Each photovoltaic installation should be equipped with a fire protection system. A protection device automatically shuts down the installation in case of fire, thus providing for additional safety.
Preventive fire protection
Overheated solar cables, abrasion by wind, and damages caused by martens can quickly lead to a short circuit in the solar installation, possibly followed by an arc-fault. A DC arc-fault is a very feared phenomenon for it produces over 6,000°C and cannot be extinguished by conventional means, posing significant risks even to firefighters. Thus, in most cases a DC arc-fault will start a fire.
The functions of a safety system can help to easily prevent a fire by automatically extinguishing an arc-fault during it’s starting process. The data cable works in this case as a long cable sensor. This cable, included in the string of solar cables, will be intentionally damaged before the solar cables get damaged by fire. This results in automatic powering down of the installation.
Inverters can be monitored, too. Being made of plastic, they can present risk in case of damage or overheating. When registering excessive temperatures, the safety system immediately shuts down the solar installation, thus cutting off the power supply of the inverter.
Furthermore, it is recommended to switch off the AC side of the solar system, too, by the means of an AC-relay. The inverter will thus be cut off both from DC and AC, which is the ideal preventive fire protection at a very low cost.
By preventing the inverter from overheating from the start, the development of flames can be avoided.
Practical for maintenance
During maintenance or cleaning work on the solar modules, a single string or the complete system can be disconnected from the supply. Maintenance work can be thus carried out danger free. Afterwards, the solar system is switched on again simply by turning the provided key.