Whole-Home Surge Protection vs Surge Power Boards: What's the Difference?

Most homes in Cairns have at least one surge power board — behind the TV, under the desk, maybe at the back of the fridge. It feels like protection. But it only covers whatever is plugged into it, and that leaves most of your house exposed.

What a surge power board actually protects

A surge board sits between one power point and the gear you plug into it. It can take the edge off a small spike on that one circuit. It does nothing for anything that isn’t plugged into it, and that includes most of the expensive stuff in the house:

• Hardwired appliances — ovens, cooktops, ducted and split-system air con, hot water systems and pool pumps are wired straight to the switchboard. There’s no plug to put a power board on.
• Big plug-in appliances — fridges, freezers and washing machines are usually plugged directly into the wall, not into a board.
• Everything else on the circuit — lights, other power points, garage doors, and anything else fed from your switchboard.

If you want to see how many of your appliances a power board can’t reach, the 30-second surge check tallies it up for your place.

What whole-home surge protection does

A whole-home surge protection device (SPD) is fitted inside your switchboard, where every circuit in the house starts. When a spike arrives, it clamps the voltage and diverts the excess to earth before it spreads through the wiring. One device covers plugged-in and hardwired gear alike, because it protects the source, not the individual appliance.

It’s a small module in the board. There’s no rewiring and no change to how anything works day to day.

Which one do you need?

They do different jobs, and you can have both.

	Surge power board	Switchboard SPD
Covers	Only what’s plugged into it	Every circuit in the house
Hardwired appliances	No	Yes
Handles big spikes	Not designed to	Yes, that’s its job
Fitted by	Anyone	A licensed electrician

The way it’s meant to work is layered. The device at the switchboard takes the big hit as it arrives. A good power board behind your TV or computer can then mop up whatever small spike gets through. If you only buy one, the switchboard unit is the one that protects the most.

Power boards wear out too

The protection in a power board is used up a little each time it absorbs a spike, and after a bad storm it may have nothing left to give. Some boards have a light that shows protection is still working, and some don’t. If a board has been through a serious storm or a few years of wet seasons, treat it as due for replacement.

Why it matters in Cairns

Storm season up here brings lightning and grid switching that regularly push spikes through the network. A surge doesn’t have to hit your house to reach it. It can come in along the power lines. That’s why protection belongs where the power enters your home rather than at a single outlet.

A switchboard SPD on a standard single-phase home is a quick job, usually under an hour. If your board is older, it may be worth a look at other things too while an electrician is there.