Peak power
The highest total output power in watts (W) that the inverter can deliver to a load for a relatively short period of time, on the order of 2 to 3 seconds. As a rule, this power is 30 - 50% more than the rated power (see above). The peak load value can be useful when calculating how the inverter works together with appliances that consume a lot of energy at start-up (vacuum cleaners, borehole pumps, power tools, etc.). The rule here is simple - the peak power of the inverter must not be lower than the starting power of the load.
Operating voltage PV
The operating range of the inverter is usually located between the starting voltage and the maximum voltage. This interval is indicated in volts.
Short circuit current
The maximum solar panel short circuit current that the inverter can accept without the risk of breakdown or emergency shutdown. The parameter is usually indicated in amperes.
Functions
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UPS function. Inverters with a UPS function automatically switch to battery-powered mode when there is insufficient power generation from solar panels or in cases where the main power source is disconnected. This ensures load redundancy. Note that switching may not occur instantly, but with a certain delay (about 10-30 ms).
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Connecting the generator. Inverters that support the generator connection function significantly increase the reliability and efficiency of autonomous solar energy systems. In practice, the function can be implemented in several basic ways. First, the system can automatically turn the generator on and off depending on the battery charge level or current power consumption, ensuring efficient use of resources and minimizing fuel consumption. Secondly, switching the load to the generator can be carried out when there is a shortage of electricity generation from solar panels. And thirdly, the generator can be used to maintain an optimal battery charge level so that the system is in full readiness at any time.
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Parallel connection. The inverter has special connectors through which two or more devices can be connected to a single electrical network. Parallel connection is used when one inverter is not able to pull the entire load from solar panels and the input power exceeds the capabilities of the device itself.
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Built-in monitoring. The presence of a built-in monitoring module on board the inverter, which collects information about the productivity of solar panels, allows you to monitor energy production and consumption, as well as monitor the performance of the system as a whole. Moreover, these parameters can often be viewed and controlled in real time (including through a mobile application for a smartphone). The monitoring module is usually connected to the Internet via a Wi-Fi network.
Protection
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Overload protection. A protection system against connecting an off-design load whose power consumption exceeds the capabilities of the inverter for solar panels. In such situations, the power to the outlets is automatically turned off, since overloading the device promises failure and even fire. Triggering of the protection is usually accompanied by a sound and/or light signal.
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Overheat protection. This protection is triggered when the temperature inside the inverter rises critically. When such situations occur, the device turns off, which avoids breakdowns. In the future, some models will automatically turn on when the temperature normalizes, while others must be turned on manually. Note that overheating is caused not only by malfunctions, but also by completely normal reasons - for example, long-term operation at high air temperatures. Typically, overheating protection is accompanied by a sound and/or light signal.
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Protection against ↑ or ↓ battery voltage. A protection system that prevents the inverter from being supplied with excessively high or excessively low voltage from the batteries. When the operating voltage range is exceeded, the device automatically turns off to avoid breakdowns and other troubles. A sound and/or light signal can warn of protection activation.
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Short circuit protection. Protec
...tion that is triggered when the output current increases critically (for example, due to a foreign metal object getting between live parts of the load). To avoid breakdowns and failure, the power at the inverter output is automatically turned off. Triggering of the protection system is usually accompanied by a sound and/or light signal.
— Reverse polarity protection. Protection system in case of incorrect polarity of connection. If the “plus” and “minus” do not match, the inverter is disconnected from the power supply in order to avoid damage to the electronic components. Notification of protection activation is often provided by a sound and/or light signal.
— Protection class. The class of protection against dust and moisture provided by the inverter housing for solar panels. Indicated according to the IP standard by two numbers: the first (from 1 to 6) means resistance to penetration of foreign objects and dust, the second (from 1 to 8) - protection from moisture. The higher the number, the higher the level of protection provided. Also note that instead of the first digit in the designation of the protection class, “X” may be indicated - for example, IPX7. In this case, the device is not certified for dust protection, although in fact the level of such protection may be quite high. So, in the example with moisture resistance “7”, the case can be completely immersed in water - which means it is closed very tightly from dust.
The IP protection level is especially important to consider when choosing models for outdoor use and installation in rooms with high humidity levels - they are the ones most susceptible to adverse environmental influences. A high IP class will guarantee stable operation of the inverter for solar panels in such difficult conditions.Display
The presence of its own display provides more visual control of the device’s operation. Various operating characteristics can be displayed on the screen: current electricity generation, load level, voltage and frequency in the network, operating mode, battery charge, etc. Inverters are equipped with both simple monochrome displays and full-fledged color panels for visual visualization of parameters.