The wattage maths nobody explains

A standard wall socket and a standard power board share the same 10-amp circuit, rated at 2,400 watts. That's the ceiling, and it's shared by everything plugged into that socket, not per device.

The working number to keep in your head is 1,920 watts, about 80 percent of that 2,400 watt rating. That buffer exists because most appliances draw more current at startup than while running, a fridge compressor or an air conditioner kicking in spikes higher than its steady state draw. Low draw devices, chargers, modems, a TV, a couple of lamps, will sit well under 500 watts combined even with six things plugged in. Then someone adds a kettle, an iron, a heater, or an air fryer, and that single device alone can eat the entire circuit.

Why daisy chaining is worse than just too many things plugged in

Plugging a second power board into the first doesn't create a second circuit. It routes the second board's entire load through the first board's internal wiring before any of that current reaches the wall. The first board was never rated to carry both loads at once, and its internal contacts and cabling are the weakest point in the chain, not the wall socket.

This is the exact pattern I see most often on jobs in the Parramatta area: a power board behind a TV unit or under a desk, with a second board plugged into it to cover the shortfall, usually in homes built before open plan living rooms had this many devices in them. It works fine for months, until the day it doesn't.

What's actually safe to run together

Anything low draw is fine to share a board, phone chargers, laptop chargers, a modem, LED lamps, a TV. What should never share a board with anything else: kettles, toasters, heaters, hair dryers, irons, and air fryers. These are single point loads that can eat an entire circuit on their own, and they need their own outlet, not a shared one.

A fridge in particular should be on its own dedicated point, not sharing a board with anything, because it's a continuous load running around the clock, not an occasional one.

When it's a power board problem versus a switchboard problem

If you're reaching for extra power boards because there simply aren't enough outlets in the room, that's not a power board problem, it's a wiring problem, and a power board is a workaround, not a fix. The proper fix is an extra power point installed on its own circuit, or in older homes, a broader look at whether the switchboard has the capacity for how the home is actually being used now.

If your board trips every time a couple of these devices run together, that's the switchboard telling you something, not the power board.