Euro efficiency
The European inverter efficiency is measured based on several load values (e.g. 10%, 30%, 50%, 100%), which better reflects the actual operating conditions of the device. Indeed, in fact, inverters rarely operate at full power in constant mode. To calculate the Euro index, the weighted average of the inverter efficiency at different load levels is taken into account. Note that there is no single generally accepted formula here - it may vary depending on the specific standard or equipment manufacturer. Nevertheless, Euro efficiency allows you to more accurately assess the efficiency of the inverter under conditions of partial and full power use
Rated power
The rated output power of the inverter, expressed in volt-amperes (VA). Essentially, this value is equivalent to power in watts (W).
This parameter refers to the power that the device can continuously deliver to consumers. When choosing based on this parameter, ensure that the rated power of the inverter exceeds the expected load power by approximately 15-20%. Additionally, keep in mind that some electrical appliances (particularly those with electric motors, such as vacuum cleaners, refrigerators, etc.) consume significantly more energy at startup than during regular operation. For such loads, it's important to check the peak power of the inverter (see the relevant paragraph) — it should be higher than the starting power of the load.
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.
Rated AC current
The current strength that the device is capable of stably and safely delivering when operating in rated mode (i.e. for the longest possible time without the risk of overloads and failures). The indicator is expressed in Amperes (A).
Maximum AC power
The maximum current in amperes (A) that the inverter, when operating, is capable of outputting without overloads or failures.
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.
Noise level
The noise level in decibels (dB) produced by the inverter during operation. The lower this indicator, the more comfortable the use of the equipment will be, which is especially important for residential premises.
Note that decibels are a non-linear quantity, so the easiest way to assess the noise level is to use comparative tables. Here is a simplified table for the range that most modern inverters fall into:
35 dB – conversation in muted tones;
40 dB – quiet conversation; maximum noise level allowed in residential premises during the daytime;
45 – 50 dB – conversation in a normal tone;
55 dB - background noise in an office without special noise sources;
60 dB - loud conversation;
65 dB - city street with average traffic intensity;
70 dB - a conversation between several people in a raised voice.
Operating temperature
The range of ambient temperatures in which the solar panel inverter is guaranteed to maintain normal operation. Here it is necessary to focus on the expected minimums and maximums of temperatures. Moreover, for operation in the cold season, it is worth paying close attention to models with the ability
to operate at sub-zero temperatures.