Can I run multiple appliances at once on my inverter?

Yes – as long as the total running wattage of your appliances stays below the inverter’s continuous power rating, and their combined start-up surge doesn’t exceed the surge capacity. Always allow a buffer to avoid tripping the system.

What happens if I exceed the inverter’s surge rating?

If your appliances draw more than the inverter's surge capacity during start-up, the inverter may shut down or enter protection mode. In worst-case scenarios, repeated overloading can damage the inverter.

How do I know the surge wattage of my appliances?

Check the appliance’s manual or data plate. If not listed, a general rule is that devices with motors (fridges, pumps, compressors) draw 2–3 times their running power at start-up. When in doubt, size up your inverter or ask a 12V expert.

Understanding Your Inverter: Continuous Load vs Start-Up Surge

When you're setting up your off-grid 12V system, choosing the right inverter is critical. One of the most common points of confusion is the difference between continuous load and start-up surge. If you don’t get this right, you could end up with an inverter that shuts down when you need it most – even if you think you’ve sized it correctly.

Here’s what you need to know.

What Is Continuous Load?

The continuous load rating refers to how much power (in watts) your inverter can deliver constantly, without overheating or shutting down. This is the core power output you should size your inverter around.

For example, the KickAss 1000W Pure Sine Wave Inverter can safely run appliances that draw up to 1000W continuously – think laptops, TVs, coffee machines, and small fridges. If your total load exceeds this for an extended time, the inverter will likely trip out or enter protection mode.

What Is A Start-Up Surge?

Some appliances draw a quick, powerful burst of energy the moment they start – especially ones with motors or compressors. This is called the start-up surge or peak load, and it's where your inverter’s surge rating matters.

All KickAss inverters are designed to handle surges up to 200% of their continuous rating. That means:

1000W Inverter → 2000W surge
2000W Inverter → 4000W surge
3000W Inverter → 6000W surge

This short burst (usually lasting a few seconds) gives you the headroom to start up gear like:

12V/240V fridges and freezers
Water pumps
Induction cooktops
Power tools and air compressors

So while a fridge might only draw 120W when running, it may spike to 1000W or more at start-up. If you’re using a 1000W inverter without enough surge capacity, it may trip out or fail to start the fridge at all – even though the running load is well within limits.

Real-World Example

Let’s say you’ve got a setup with a fridge (120W running, 1000W start-up), a fan (50W), and some lighting (100W). That’s only 270W of continuous draw – easily handled by the 1000W inverter.

But when the fridge kicks in, the surge jumps to over 1000W. This is right on the limit of the KickAss 1000W Inverter’s 2000W surge capacity, and it’ll probably cope just fine.

Now imagine you’ve added an induction cooktop (1500W running, 2500W surge). Suddenly, the 1000W inverter isn’t going to cut it. You’ll need a 2000W or possibly even 3000W Inverter, depending on how much you plan to run at the same time.

Planning Your System

When deciding which inverter is right for you:

Add up the running wattage of all appliances you want to use together.
Check the surge ratings of appliances with motors or compressors.
Choose an inverter with enough continuous and surge capacity for your total load – with some buffer.

It’s always better to oversize slightly than push your inverter to the edge. Not only will it perform more reliably, but it’ll also run cooler and last longer.

Ready to Go?

Whether you're running a basic 12V setup or a full off-grid kitchen, KickAss has the right inverter for the job – they all provide clean, reliable, pure-sine-wave power that will keep all your AC appliances singing. Explore the full range of KickAss inverters here.

Still not sure which size you need? Get in touch – our team of experts will be happy to help. Call into one of our retail store, or call 07 3123 4715.