Inverter Size for RV: Finding the Perfect Fit

When it comes to RV living, having a reliable power source is crucial for ensuring a comfortable and convenient experience on the road. One essential component that enables you to power various appliances and electronics while off-grid is an inverter. However, determining the right inverter size for your RV can be a bit challenging if you're not familiar with the technicalities involved. In this blog post, we'll explore what an inverter is, how it works, and guide you through the process of deciding the appropriate inverter size for your RV. We'll also cover important considerations when buying an inverter and shed light on the differences between RV inverters and converters.

What is an Inverter and How Does It Work?

An inverter is an electronic device used to convert direct current (DC) power into alternating current (AC) power. It is commonly used in various applications, including residential and commercial power systems, renewable energy systems, and electronic devices.

The primary purpose of an inverter is to change the form of electrical power. DC power typically comes from sources such as batteries, solar panels, or fuel cells, which provide a constant voltage or current flow in one direction. On the other hand, most household appliances require AC power, which oscillates in a sinusoidal waveform and changes direction periodically.

The working principle of an inverter involves several stages:

Inversion: The input power source (DC power) is fed into an inverter circuit, which employs electronic switches, typically metal-oxide-semiconductor field-effect transistors (MOSFETs) or insulated gate bipolar transistors (IGBTs). These switches rapidly turn on and off in a specific sequence, modulating the DC voltage to produce an AC output waveform.

Pulse Width Modulation (PWM): The switches in the inverter circuit are controlled by a technique called Pulse Width Modulation. PWM adjusts the width (duration) of the switch-on time within each period of the AC waveform. By varying the width of the pulses, the inverter can control the magnitude and frequency of the output AC signal.

Output Filtering: The resulting AC waveform from the inverter circuit may still contain some harmonic distortions or fluctuations. Therefore, the output is usually passed through an output filter to smooth out any ripples and provide a clean sinusoidal waveform that closely resembles the standard AC power.

Overall, the inverter continuously converts the DC power input into a high-frequency AC waveform, which is then filtered and stepped up or down in voltage if necessary. This enables the inverter to supply AC power that is compatible with various electrical devices and systems, allowing them to function as if they were connected to a conventional AC power grid.

How to Decide Inverter Size for RV?

Now that we understand the basic functionality of an inverter, let's discuss how to determine the appropriate inverter size for your RV. The size of an inverter is typically measured in watts and is directly related to the power requirements of the devices you intend to run simultaneously.

To calculate the inverter size you need, follow these steps:

1. Identify the power consumption: Make a list of all the appliances and devices you plan to run simultaneously using the inverter. Note down their power consumption in watts. You can usually find this information on the appliance labels or user manuals.

2. Determine the starting power requirements: Some appliances, like air conditioners or refrigerators, require extra power when they initially start up. This initial surge is known as the "starting power" or "surge power." Identify the appliances with starting power requirements and make a note of their surge wattage. (The standard wattage refers to the amount of power required for the machine to operate continuously, whereas the surge wattage represents the energy needed to initially start the device.)

3. Add up the power requirements: Add up the power consumption of all the devices you listed in Step 1. Be sure to include the surge wattage for appliances with starting power requirements.

4. Choose an inverter size: Based on the total power requirements calculated in step 3, select an inverter size that is slightly larger than the total power to ensure efficient operation. It's generally recommended to have an inverter with a capacity around 20% higher than your total power requirements to handle any power spikes or future additions to your RV's electrical system.

Let's say you need 3000 watts of running power and 4000 watts of surge power to start your appliances. Then you need an inverter with a power capacity 20% higher than the total surge power:

4000watts x 1.20 =4800watts

This means you need an inverter with at least 5000W size.

What to Consider When Buying an Inverter for RV?

When purchasing an inverter for your RV, there are a few important factors to consider to ensure you make the right choice. Here are some key considerations:

Power Requirements

Determine the power needs of your RV appliances and devices. Calculate the total wattage you will be using simultaneously to ensure the inverter can handle the load. Consider both the continuous power (wattage required for normal operation) and peak power (wattage required during startup or when devices have high initial power demands).

Inverter Type

One crucial aspect to evaluate is the type of power output the inverter provides. Pure sine power inverters generate power that closely resembles the smooth, clean power supplied by utility companies. On the other hand, modified sine wave power inverters produce a rougher power output. While modified sine wave inverters are more affordable, they may not be compatible with all devices and can potentially cause issues or damage certain electronics.

Battery Connection

Verify the compatibility and connection requirements between the inverter and your RV's battery system. Ensure that the inverter can be connected properly and safely to the battery bank.

Brand and Reliability

Choose a reputable brand known for manufacturing reliable and durable inverters. Read reviews and consider customer feedback to gauge the overall performance and reliability of the inverter.

If you have no idea which brand to choose, Anker is worth looking into. The Anker Solar Generator 757 includes a Powerhouse 1229Wh with three 100W Solar Panels. The Powerhouse 1229Wh provides a substantial capacity, allowing for extended usage of various devices and appliances. The three included solar panels convert up to 23% of sunlight into energy, enabling efficient solar charging while on the go. Equipped with multiple ports, including fast-charging USB-A,C, and AC outlets, the Anker Solar Generator 757 is a versatile and reliable solution for your RV adventures.

What's the Difference Between RV Inverter and Converter?

Many RV owners often confuse inverters with converters, but these two devices serve different purposes. While an inverter converts DC power from the batteries into AC power for running appliances, a converter, as the name suggests, converts AC power from an external source (like a campground hookup or generator) into DC power to charge the RV's batteries and power DC-based devices within the RV. Both inverters and converters are essential for an RV's electrical system, but their functions and operation differ significantly.

Conclusion

Selecting the right inverter size for your RV is crucial for ensuring a reliable power supply and an enjoyable experience on the road. By understanding the basics of inverters, following the calculation process for sizing, considering important factors during the buying process, and distinguishing between inverters and converters, you can make an informed decision that suits your power needs. Remember, it's always better to have an inverter with slightly higher capacity than you require to accommodate potential power surges and future additions to your RV's electrical system. So, invest wisely and enjoy the convenience of powering your RV appliances while embracing the freedom of off-grid adventures.