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: 27.06.2025 00:22

A fuse is a non-resetable over current circuit protector.
The third is lightning and “how it gets conducted into a home.”
so, what happens?
New Study Reveals the #1 Sleep Mistake That Harms the Brain - AOL.com
but this device (an Inductor) … impedes the rapid changes in the current.
There are two important concepts here.
So combined with a device called a MOV or Metal-oxide-resistor, then forms the 3rd part of a “surge suppressor “.
Nasa delays next flight of Boeing’s alternative to SpaceX Dragon - The Edge Malaysia
But during the surge, the fuse will not blow if it is a longer duration and lower value )10 to 50%).
the problem then depends on "how fast does the fuse operate?".
Here is a simplified AC power diagram.
New Discovery of Deep Sea 'Spiders' Is Unlike Anything We've Seen Before - ScienceAlert
For this case there are devices called Metal oxide varistors (MOV).
2024–10–00 [ Ammar Mahdi ] Ammar Mahdi
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.
WWDC 2025: iOS 26 Rumored Features - MacRumors
Now when you have a certain ac resistance, then a current flows in a loop.
So, it’s possible that these devices from Trip Lite have addition suppression devices, these ones seem to be sturdy.
Fuses, on their own, then operate much slower than the MOV variable resistance, during the lightning strike.
Will Ukraine eventually return to Russia's sphere of influence?
This is 'the assistant's answer'
This is where the MOV conducts again, and dissipated the energy.
This is where this question deviates from being a 'generic' question, and becomes more specific.
2024–10–16 [ OO OLAOYE OYEBODE ]
[old diagram got deleted by accident]
nine
What is something you saw while on an airplane that you couldn't believe?
A circuit breaker is similar, but is resettable.
“ 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”
eight
Summer McIntosh Posts 4:23.65 400 IM to Break Her Own World Record - SwimSwam
Edit 2024–10.
The bolt then partially travels down the line to your home.
But… the neutral is now “floating” because of the 1 ohm resistance.
Bruins Sign Victor Soderstrom to One-Year, Two-Way Contract - NHL.com
At one ohm, the resistor has a maximum of 1 watt power.
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.
Mohan forgets that a fuse is a one-time device, and needs to be replaced if it is tripped.
Junk Food Alert: Our Bodies Treat Ultra-Processed Foods Like Foreign Invaders! - Glass Almanac
2024–10–11 [Bobby Sanchez Bobby Sanchez ].
He then describes the function of a fuse.
so, the loop of wire then, when put together with another loop reduces the ‘noise’ on a power line.
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.
It’s been three xxx five werks, and there has been no response to my follow on query on his Commment to my answer.
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.
There are three different concepts here that are getting confused.
An AC voltage/ current source, and an ac inductive load.
So, the voltage could go up to 500 volts, and the fuse will not open up.
The other is “what does a “fuse” do?”
But it can get overloaded, and no longer works.
This is the picture of an electronic coil of wire wound around a core of magnetic material.
These devices are installed between the “hot” and “neutral” and protective ground.
“ A fuse is a device which protects the (circuit) against overload and short circuit.”
2024–10–11 [Victor Olarewsju Victor Olarewaju ]
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.
These are simplified answers to the original question, and does not change anything I wrote above.
It seems Mohan does not understand the difference between a comment and an Answer.
P = e* I, so since I is 16 amps, then the voltage dropped is 1/16 volt or 0.0650 volts.
He then describes Rainy Season and Lightning.
Is the question then , "why buy a surge supressor, if the fuse alone protects the electronic circuits from a lightning bolt?".
Barnstars:
What is lightning?
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?
And this is the problem alone. Is the power supply in the equipmemt designed with a lightning strike in mind? Some yes, others, no.
(There is no concept of polarity, in the loop because the current changes direction 100 to 120 times a second (power frequency).
a photo is worth a thousand words.
He then asserts :
One
OK, this is Mohan Rajaratnam’s definition of a Surge suppressor.
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.
Upvotes:
Would individual surge supressors have save this equipment? most likely, since the surge supressor would take the jolt instead of the electronic components.
what exactly is a ‘surge’ protector?
This device then solves the entire problem.
[image of Common-mode choke]
At least they know the answer if they wanted it.
(Dc diagram shown, AC is similar).
2024–10–10[John johnson John Johnson ]
but I think this circuit , shows a few more pieces.
2024–10–14 [Omar Gharbi Omar Gharbi ]
First Sentence:
One is “what exactly is in a ‘surge protector’ ? ”
In schematic diagrams this is the symbol for a fuse:
Because the load is inductive, the current lags the voltage.(by a bit).
When the current is 200% of the rated value , it will “go open” (the link metal melts) and protect the device.
“ … to protect building, lightning arrestor, is provided above building and directly connected to earth.”
The MOV will conduct when the voltage exceeds 50% of line voltage.
What does a fuse do?
If the nominal power is 4,000 watts then the current at 230volts is 16 amps.
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.
I post the exact comment here.
It also is a device that limits the change in current flow.
This one hit behind the barn.
Can the fuse protect the electronic devices from lightning instead of a surge protector.