Comparison Must PV18-1512 VPM vs Huawei SUN2000-2KTL-L1

— Autonomous inverter. Voltage and power converters that are not connected to an external electrical network. They are supposed to be used as part of autonomous photovoltaic systems - such inverters generate electricity, which is spent exclusively for the needs of the household. It can be consumed directly by household appliances or accumulated in batteries. This type of inverter is often called off grid.

— Network inverter. Inverters operating synchronously with the external power supply network. They are designed to convert solar energy into alternating power with the parameters of the general network. Grid-connected inverters are used in battery-free systems - all generated energy is used for own consumption, and the excess is transferred to the network at a “feed-in tariff”. To do this, some indicators of generated electricity are adjusted, in particular, amplitude differences are eliminated, the network frequency is equalized, etc. Grid-tied inverters are also known as on-grid inverters.

— Hybrid inverter. Battery-grid inverters are peculiar hybrids of autonomous and network converters. Actually, this is where the name hybrid comes from. Inverters of this type work with battery chains, and excess electricity is sent to the general network. This ensures the energy independence of the system based on solar panels with the ability to use the...energy accumulated in the batteries without disconnecting from the network. For example, if DC power is prioritized, power is primarily supplied from batteries, and any energy shortages are supplied from the external grid. This comes in handy in case of bad weather conditions or insufficient power generated by solar panels. If electricity is generated in excess, the excess energy is released into the general network at a “feed-in tariff”.

— Inverter for campers (motorhomes). Such narrow-niche inverters usually work in conjunction with a branded charging station - while staying at a campsite, it charges the vehicle’s battery. And while driving, such inverters are connected to the car’s alternating power generator and with their help, the energy reserves in the battery cells of the charging station are replenished.

Inverter efficiency for solar panels.

The efficiency indicator is the percentage ratio between the amount of energy that the device delivers to the load and the energy consumed from the solar panel. The higher this parameter, the more efficient the operation of the device and the lower the losses during conversion. In modern inverters for solar panels, efficiency values of up to 90% are considered average, and above 90% are considered good.

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

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.

The rated output power of the inverter, expressed in watts (W).

This parameter means the power that the device can provide to consumers for an unlimited time. It is necessary to choose according to this indicator so that the rated power of the inverter covers the power consumption of the expected load by approximately 15-20%. It is also worth considering that some electrical appliances (in particular, units with electric motors - vacuum cleaners, refrigerators, etc.) consume significantly more energy when starting up than after entering the mode. For such a load, it is also necessary to clarify the peak power of the inverter (see the corresponding paragraph) - it should be higher than the starting power of the load.

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.

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).

The maximum current in amperes (A) that the inverter, when operating, is capable of outputting without overloads or failures.

The form that the graph of the voltage produced by the inverter has.

This can be a pure sinusoid with a high quality output signal - the voltage on the graph changes evenly, without sudden jumps and drops. It is as close as possible to the parameters of conventional sockets. Models with pure sine wave voltage allow you to connect almost any load - even delicate electronics that are sensitive to power quality. On the other hand, such quality requires the use of complex control circuits and significantly affects the cost of the inverter, and there is not always a real need for it.

Another option for the output signal shape is a modified (approximated) sine wave. As a rule, such graphs are constructed from stepped lines, sometimes quite large. The disadvantage of the modified sine is the inability to work with sensitive equipment (for example, where asynchronous motors or transformers are installed). However, in the absence of such a need, this moment cannot be called critical.