Is Your Inverter Wiring Sized Correctly?

When we’re diagnosing a van electrical system, we often find problems that aren’t immediately obvious.

The inverter might be working. The system might appear to function normally. But that doesn’t necessarily mean everything was installed correctly.

Take this 3,600-watt inverter we recently looked at. The inverter itself wasn’t the issue. The concern was the wiring supplying it.

The system had been wired with dual 6 AWG cables. Without even running the full calculations, we could tell that was smaller than what we would normally use for an inverter of this size. For comparison, we’d typically use larger cable on a 3,000-watt inverter.

Why does wire size matter?

In a van electrical system, the wiring has to be sized appropriately for the amount of current the system can draw.

An inverter converts DC power from your batteries into AC power for things like appliances, tools, chargers, and other equipment. The larger the inverter, the more current it can potentially pull from the battery bank.

That means the cables connecting the battery system to the inverter need to be capable of safely handling that load.

Using undersized wiring can create excessive voltage drop and heat, and it can prevent your system from performing the way it should. That's why cable sizing isn't something you want to guess at or base on what happened to work in someone else's van.

What we're doing with this system

Rather than simply leaving the existing cables in place, we're going to remake them using appropriately sized cable.

We're also looking at the rest of the installation while we're there, including the protection and connections around the system.

That's an important part of electrical work: don't just fix the one thing you noticed. Look at the system as a whole.

A component may be perfectly functional while the wiring around it isn't appropriately sized or installed. Catching those issues while you're already working on the system can prevent bigger problems later.

The takeaway for DIY builders

If you're installing an inverter in your van yourself, don't choose your cable size based on a quick internet search or because someone used the same size in their build.

Your wire size should be based on the specific inverter, expected current, cable length, system voltage, and applicable electrical requirements.

And when you're working with a high-powered electrical system, this is one of those areas where getting a professional set of eyes on your plan can be well worth it.

Your inverter doesn't just need to turn on.

The entire system needs to be designed so it can safely handle the load you're asking it to carry.

If you're unsure whether your van's electrical system was wired correctly, or you're planning an upgrade and want to make sure you're doing it right, we can help.

Book a diagnostic session with Adventure Life Vans to have your system evaluated before you start replacing components or chasing problems.