What exactly is the difference between a surge protector and a fuse? Can a fuse protect the electronic devices from lightning instead of surge protector?
Last Updated: 24.06.2025 05:56

These devices are installed between the “hot” and “neutral” and protective ground.
This one hit behind the barn.
Now when you have a certain ac resistance, then a current flows in a loop.
This is where the MOV conducts again, and dissipated the energy.
What is lightning?
This is a high voltage low current spike that comes down the line because of the power poles being struck, and the voltage suppressors activating on the primary side of the transformer.
Stocks to Open Flat as Trade Pact Details Awaited: Markets Wrap - Bloomberg
It also is a device that limits the change in current flow.
This is a photo where a lightning bolt took out a home's complete mains distribution box, and a lot of electronic gear as well.
2024–10–10[John johnson John Johnson ]
This is the picture of an electronic coil of wire wound around a core of magnetic material.
For this case there are devices called Metal oxide varistors (MOV).
One
Why are so many people getting sick from eating cucumbers? - NBC News
but this device (an Inductor) … impedes the rapid changes in the current.
There are three different concepts here that are getting confused.
So, it’s possible that these devices from Trip Lite have addition suppression devices, these ones seem to be sturdy.
At the secondary, it is 1000 times less.)turns ratio). If it gets hit with a 100,000 volt bolt of lightning then the voltage arrestors conduct and clamp the voltage down to line voltage, ( but a small amount leaks down the line). This is the problem.
This device then solves the entire problem.
so, what happens?
How to watch the 2025 Tony Awards on Sunday - NPR
At one ohm, the resistor has a maximum of 1 watt power.
Because the load is inductive, the current lags the voltage.(by a bit).
“ … to protect building, lightning arrestor, is provided above building and directly connected to earth.”
Barnstars:
But it can get overloaded, and no longer works.
Here is a simplified AC power diagram.
He then describes Rainy Season and Lightning.
At least they know the answer if they wanted it.
There are two important concepts here.
The sun's poles have flipped. A spacecraft is watching what happens next. - Mashable
What does a fuse do?
a photo is worth a thousand words.
A circuit breaker is similar, but is resettable.
Is sunscreen toxic? The UV truthers on the internet sure think so. - The Boston Globe
When the current is 200% of the rated value , it will “go open” (the link metal melts) and protect the device.
This is 'the assistant's answer'
It’s been three xxx five werks, and there has been no response to my follow on query on his Commment to my answer.
“ A fuse is a device which protects the (circuit) against overload and short circuit.”
2024–10–11 [Victor Olarewsju Victor Olarewaju ]
Edit 2024–10.
Why does it feel like music today is boring?
He then asserts :
2024–10–11 [Bobby Sanchez Bobby Sanchez ].
So, the voltage could go up to 500 volts, and the fuse will not open up.
Xbox finally reveals handheld console after decade of speculation - BBC
(Dc diagram shown, AC is similar).
There is no harm in having the surge suppressor along with the fuse in the circuit. The fuse will not open up until the current melts the link. This will take time, and in the interim, that jolt will get transmitted into the power supplies.
eight
A fuse is a non-resetable over current circuit protector.
In schematic diagrams this is the symbol for a fuse:
If the nominal power is 4,000 watts then the current at 230volts is 16 amps.
2024–10–00 [ Ammar Mahdi ] Ammar Mahdi
I post the exact comment here.
OK, this is Mohan Rajaratnam’s definition of a Surge suppressor.
But… the neutral is now “floating” because of the 1 ohm resistance.
P = e* I, so since I is 16 amps, then the voltage dropped is 1/16 volt or 0.0650 volts.
First Sentence:
2024–09–27 [ Mohan Rajaratnam Mohan Rajaratnam ] . Thinks you can get free electricity from nothing : Mohan Rajaratnam's answer to Is it possible to generate free electricity at home using a magnet or other low-cost methods? If so, how does it work?
This is an electronic circuit designed to clamp voltages so that the Voltage Potential that appears at the outlet is never going to exceed the nominal value.
(There is no concept of polarity, in the loop because the current changes direction 100 to 120 times a second (power frequency).
The other is “what does a “fuse” do?”
Is the question then , "why buy a surge supressor, if the fuse alone protects the electronic circuits from a lightning bolt?".
The MOV will conduct when the voltage exceeds 50% of line voltage.
Once the voltage goes over 0.0650 volts, then this fact can be used to amplify the difference, and turn the circuit breaker off , furthur down the line. Essentially that is what a RCD/GFCI does, it compares the incoming current, to the outgoing current, and if the difference between the two currents is over 5mA, then it trips the circuit breaker.
Lightning arrestor is a spark-gap device, and can be installed anywhere. What is important, is that the wire is thick enough to withstand the lightning bolt and conduct the energy away from the building.
One is “what exactly is in a ‘surge protector’ ? ”
The bolt then partially travels down the line to your home.
nine
[old diagram got deleted by accident]
But during the surge, the fuse will not blow if it is a longer duration and lower value )10 to 50%).
And this is the problem alone. Is the power supply in the equipmemt designed with a lightning strike in mind? Some yes, others, no.
so, the loop of wire then, when put together with another loop reduces the ‘noise’ on a power line.
the problem then depends on "how fast does the fuse operate?".
This is where this question deviates from being a 'generic' question, and becomes more specific.
Fuses, on their own, then operate much slower than the MOV variable resistance, during the lightning strike.
Mohan forgets that a fuse is a one-time device, and needs to be replaced if it is tripped.
“ A surge suppressor is the one which is connected at the input supply so that when there is a sudden change voltage it bypasses thereby protecting the (circuit) and electronic components”
An AC voltage/ current source, and an ac inductive load.
The third is lightning and “how it gets conducted into a home.”
These are simplified answers to the original question, and does not change anything I wrote above.
Upvotes:
2024–10–16 [ OO OLAOYE OYEBODE ]
It seems Mohan does not understand the difference between a comment and an Answer.
but I think this circuit , shows a few more pieces.
Can the fuse protect the electronic devices from lightning instead of a surge protector.
So combined with a device called a MOV or Metal-oxide-resistor, then forms the 3rd part of a “surge suppressor “.
Would individual surge supressors have save this equipment? most likely, since the surge supressor would take the jolt instead of the electronic components.
[image of Common-mode choke]
2024–10–14 [Omar Gharbi Omar Gharbi ]
what exactly is a ‘surge’ protector?
He then describes the function of a fuse.