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?
09.06.2025 10:35

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.
Is the question then , "why buy a surge supressor, if the fuse alone protects the electronic circuits from a lightning bolt?".
Mohan forgets that a fuse is a one-time device, and needs to be replaced if it is tripped.
2025 NHL Draft Combine Notebook: What we learned - Daily Faceoff
What does a fuse do?
Now when you have a certain ac resistance, then a current flows in a loop.
One
One of the Best Xbox Series X Games Is $56 Off Right Now - ComicBook.com
Upvotes:
so, what happens?
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?
The third is lightning and “how it gets conducted into a home.”
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.
So, the voltage could go up to 500 volts, and the fuse will not open up.
10-year Treasury yield rises ahead of key jobs report - CNBC
A fuse is a non-resetable over current circuit protector.
First Sentence:
It seems Mohan does not understand the difference between a comment and an Answer.
Ask Ethan: What are the "first stars" in the Universe? - Big Think
But during the surge, the fuse will not blow if it is a longer duration and lower value )10 to 50%).
2024–10–10[John johnson John Johnson ]
An AC voltage/ current source, and an ac inductive load.
Popular chicken chain shares, massive expansion plan - TheStreet
So, it’s possible that these devices from Trip Lite have addition suppression devices, these ones seem to be sturdy.
[old diagram got deleted by accident]
nine
Top prospects for 2025 Draft arrive in Buffalo for Scouting Combine - NHL.com
eight
There are two important concepts here.
When the current is 200% of the rated value , it will “go open” (the link metal melts) and protect the device.
what exactly is a ‘surge’ protector?
OK, this is Mohan Rajaratnam’s definition of a Surge suppressor.
2024–10–11 [Victor Olarewsju Victor Olarewaju ]
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.
He then describes the function of a fuse.
but I think this circuit , shows a few more pieces.
Samsung teases Galaxy Z Fold 7 with an absolutely bizarre ‘Ultra experience’ [Video] - 9to5Google
Barnstars:
For this case there are devices called Metal oxide varistors (MOV).
A circuit breaker is similar, but is resettable.
5 Things to Know Before the Stock Market Opens - Investopedia
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.
“ 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”
He then asserts :
Your Brain Wrinkles Are Way More Important Than We Ever Realized - ScienceAlert
Fuses, on their own, then operate much slower than the MOV variable resistance, during the lightning strike.
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.
The bolt then partially travels down the line to your home.
The MOV will conduct when the voltage exceeds 50% of line voltage.
Here is a simplified AC power diagram.
These are simplified answers to the original question, and does not change anything I wrote above.
This is where this question deviates from being a 'generic' question, and becomes more specific.
Because the load is inductive, the current lags the voltage.(by a bit).
This is 'the assistant's answer'
It also is a device that limits the change in current flow.
If the nominal power is 4,000 watts then the current at 230volts is 16 amps.
P = e* I, so since I is 16 amps, then the voltage dropped is 1/16 volt or 0.0650 volts.
This is where the MOV conducts again, and dissipated the energy.
Edit 2024–10.
a photo is worth a thousand words.
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]
the problem then depends on "how fast does the fuse operate?".
In schematic diagrams this is the symbol for a fuse:
One is “what exactly is in a ‘surge protector’ ? ”
This is the picture of an electronic coil of wire wound around a core of magnetic material.
At least they know the answer if they wanted it.
But… the neutral is now “floating” because of the 1 ohm resistance.
But it can get overloaded, and no longer works.
2024–10–11 [Bobby Sanchez Bobby Sanchez ].
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.
These devices are installed between the “hot” and “neutral” and protective ground.
At one ohm, the resistor has a maximum of 1 watt power.
So combined with a device called a MOV or Metal-oxide-resistor, then forms the 3rd part of a “surge suppressor “.
“ … to protect building, lightning arrestor, is provided above building and directly connected to earth.”
2024–10–00 [ Ammar Mahdi ] Ammar Mahdi
“ A fuse is a device which protects the (circuit) against overload and short circuit.”
Can the fuse protect the electronic devices from lightning instead of a surge protector.
What is lightning?
The other is “what does a “fuse” do?”
And this is the problem alone. Is the power supply in the equipmemt designed with a lightning strike in mind? Some yes, others, no.
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.
(Dc diagram shown, AC is similar).
2024–10–16 [ OO OLAOYE OYEBODE ]
I post the exact comment here.
There are three different concepts here that are getting confused.
This device then solves the entire problem.
(There is no concept of polarity, in the loop because the current changes direction 100 to 120 times a second (power frequency).
He then describes Rainy Season and Lightning.
It’s been three xxx five werks, and there has been no response to my follow on query on his Commment to my answer.
This one hit behind the barn.
2024–10–14 [Omar Gharbi Omar Gharbi ]
but this device (an Inductor) … impedes the rapid changes in the current.
so, the loop of wire then, when put together with another loop reduces the ‘noise’ on a power line.