What sort of protection devices are these other sites recommending? In fact, I can't see how any of the typical devices could protect against a sustained overvoltage unless it results in an over-current fault. To do it properly, you would need to have a high current relay with upper and lower supply voltage limits.
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What sort of protection devices are these other sites recommending? In fact, I can't see how any of the typical devices could protect against a sustained overvoltage unless it results in an over-current fault. To do it properly, you would need to have a high current relay with upper and lower supply voltage limits.
That device tells you whether the power outlet is wired correctly, although it can't detect neutral-earth reversal. You still need a multimeter to measure the actual voltage.
A surge protector can only absorb a relatively tiny amount of energy for only a short time. They seem to be typically rated at 1000 joules.
240V x 40A x 100 millisec = 960 joules
240V x 400A x 10 millisec = 960 joules
They are good for absorbing those switch-on spikes which are typically responsible for pops and clicks.They do this via metal oxide varistors (MOVs). These are small disc shaped components, typically 14mm or 20mm in diameter, usually rated for 275VAC. In the presence of a sustained overvoltage these will explode, hopefully taking out the thermal fuse or glass fuse.
The other components are chokes and capacitors. These filter out high frequency electromagnetic interference (EMI).
This is a commercial product, but the explanation is sound: