Comparison Must PV18-3224 PRO vs Must PV18-3224 VPM

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

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.

The maximum allowable input power from solar panels, expressed in kilowatts (kW). Let us remember that 1 kW contains 1000 W.

When selecting an inverter based on this indicator, they are based on the total power of the solar panels involved in generating electricity. Moreover, it often makes sense to select models with an inverter input power slightly less than the maximum power of solar panels - for example, if they are shaded part of the time or for other reasons do not receive enough sunlight during the day. The power of the solar battery should not exceed the power of the inverter by more than 30%. However, for some inverters the excess can be only 10%, while for others it can be up to 100%. It is better to clarify this point in advance.

The operating range of the inverter is usually located between the starting voltage and the maximum voltage. This interval is indicated in volts.

Connection interfaces provided in the inverter design for solar panels.

- RS232. A specialized communication interface used to directly connect the inverter to a computer. As a rule, the interface provides the ability to monitor solar generation systems around the clock using a local network. Also, the RS232 connector can be used to communicate several inverters with each other, or, less often, for software updates or service testing.

- RS485. A connector often used to connect several inverters to a central hub, which, in turn, connects to a computer. This connection can be useful for setting up a solar generation system or sending monitoring data over the network.

- USB. A standard USB port is often used for configuring equipment via a wired connection to a computer or for inverter firmware updates.

- LAN (RJ45). The presence of a LAN connector (RJ45) in the inverter design. Such ports are standardly used for wired connections in computer networks using a twisted pair cable.

- Wi-Fi. Wi-Fi communication module for wireless connection of the inverter to a computer, laptop or mobile phone. Using specialized software, you can receive monitoring data from the inverter directly “over the air” - transmitting information over a Wi-Fi network eliminates the...fuss with wires.

— Bluetooth. Option to wirelessly pair the inverter with smartphones, tablets or laptops via Bluetooth. Thanks to data synchronization, the user will be able to monitor equipment performance and remotely control the inverter within range of the Bluetooth wireless network.

The protection class of the housing is traditionally indicated according to the IP standard - the “IP” marking with two numbers. The first describes protection against the penetration of dust and foreign objects. The following options may occur:

— 2. Protection against objects with a thickness of 12.5 mm or more, prevents the penetration of fingers.
— 3. Protection against objects with a thickness of 2.5 mm, in particular many tools.
— 4. Protection from objects with a thickness of 1 mm (most wires).
— 5. Complete protection from contact of the “internals” with foreign objects, resistance to dust (it can penetrate inside the case, but in scanty quantities that do not affect the operation of the device).
— 6. Completely closed housing, preventing dust from getting inside.

The second digit in the IP marking characterizes the degree of protection against moisture:

— 0. Complete absence of any protection; water ingress into the housing is not allowed.
— 1. Protection from vertical drops of water.
— 2. Protection against vertical drops when the body is tilted up to 15° from the standard position.
— 3. Protection against splashes falling on the body at an angle of up to 60° to the horizontal, the minimum indicator that allows us to talk about resistance to rain.
- 4. Protection against splashes from any direction, allows you to safely withstand rain and strong winds.
— 5. Protection from water jets from any...direction, resistance to storms.
— 6. Protection from strong water jets or strong sea waves (when the device can be completely hidden under the wave for a short time).
— 7. Possibility of short-term immersion to a depth of up to 1 m (without the possibility of constant operation in submerged mode).
— 8. possibility of long-term immersion to a depth of more than 1 m (with the possibility of constant operation in submerged mode).

The degree of IP protection is especially important to consider when choosing outdoor models - they are the ones most susceptible to adverse environmental influences. This parameter is also important when placing the inverter in rooms with high humidity levels.