Device type
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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.
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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.
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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.Network type
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Single-phase (230 V). Single-phase power is well known from classic 230 V household sockets. However, this also often includes models for other alternating voltage values - for example, 110 V.
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Three-phase (400 V). Three-phase power supply with a voltage of 400 V is used mainly for energy-hungry devices for which 230 V networks do not provide enough power. This option can be used both for private households and in the industrial sector.
— Single-phase / three-phase. Models with the ability to connect to both single-phase power supply at 230 V and three-phase power supply at 400 V. This allows them to be used with both household and industrial networks - depending on which option is more convenient at the moment.
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DC (constant voltage). This category usually includes a few inverters for campers (motorhomes) (see “Device Type”). They are designed for operation in automotive networks with a constant voltage of 12/24 V.
Maximum efficiency
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.
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
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.
Number of battery inputs
Number of points for connecting batteries to the inverter. Household models usually have one such input, while powerful and productive models may have two or even three battery inputs. Multiple inputs allow the system to be scaled by adding batteries without having to replace the inverter.
Maximum charge current
The maximum amount of direct current in amperes that the inverter can convert. If the solar panel produces a current exceeding this value, the inverter simply does not use it. This is often justified when connecting an inverter to high-power solar panels - the maximum input current of the inverter is reduced to acceptable values so that moderate-sized wires can be used to transmit energy.
