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: 02.07.2025 15:26

(Dc diagram shown, AC is similar).
Edit 2024–10.
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.
Can the fuse protect the electronic devices from lightning instead of a surge protector.
This is the picture of an electronic coil of wire wound around a core of magnetic material.
OK, this is Mohan Rajaratnam’s definition of a Surge suppressor.
How does the brain decide "what" thought to attach to a feeling?
This is where this question deviates from being a 'generic' question, and becomes more specific.
And this is the problem alone. Is the power supply in the equipmemt designed with a lightning strike in mind? Some yes, others, no.
Mohan forgets that a fuse is a one-time device, and needs to be replaced if it is tripped.
Exclusive Trump interview: A big steel deal for Pennsylvania - Washington Examiner
[image of Common-mode choke]
In schematic diagrams this is the symbol for a fuse:
2024–10–14 [Omar Gharbi Omar Gharbi ]
Astronomers Just Discovered One of the Fastest Jets Ever in a Radio-Quiet Galaxy - The Daily Galaxy
2024–10–16 [ OO OLAOYE OYEBODE ]
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?
Are you worried that the 2024 US presidential election will result in a close race?
Would individual surge supressors have save this equipment? most likely, since the surge supressor would take the jolt instead of the electronic components.
A circuit breaker is similar, but is resettable.
what exactly is a ‘surge’ protector?
Asteroid 2024 YR4 Could Strike the Moon: NASA’s Webb Telescope Warns - The Daily Galaxy
This is 'the assistant's answer'
If the nominal power is 4,000 watts then the current at 230volts is 16 amps.
2024–10–00 [ Ammar Mahdi ] Ammar Mahdi
Youth overdoses from synthetic opioids are increasing. What parents should know - CNN
One
A fuse is a non-resetable over current circuit protector.
so, the loop of wire then, when put together with another loop reduces the ‘noise’ on a power line.
Jack Betts, ‘Spider-Man’ Actor and Spaghetti Western Veteran, Dies at 96 - Variety
The bolt then partially travels down the line to your home.
He then describes the function of a fuse.
a photo is worth a thousand words.
Has anyone been spanked by their parents after becoming an adult?
An AC voltage/ current source, and an ac inductive load.
But it can get overloaded, and no longer works.
P = e* I, so since I is 16 amps, then the voltage dropped is 1/16 volt or 0.0650 volts.
Resilience spacecraft’s status after moon-landing attempt is unknown - CNN
eight
These devices are installed between the “hot” and “neutral” and protective ground.
At least they know the answer if they wanted it.
Why are people of mixed race seen as more attractive than non-mixed-race people?
So combined with a device called a MOV or Metal-oxide-resistor, then forms the 3rd part of a “surge suppressor “.
First Sentence:
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.
Instagram will finally let you rearrange your grid - TechCrunch
One is “what exactly is in a ‘surge protector’ ? ”
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.
“ A fuse is a device which protects the (circuit) against overload and short circuit.”
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.
The other is “what does a “fuse” do?”
When the current is 200% of the rated value , it will “go open” (the link metal melts) and protect the device.
Blumhouse Reveals Trailer And Poster For ‘Black Phone 2’ - Deadline
There are three different concepts here that are getting confused.
Upvotes:
He then describes Rainy Season and Lightning.
It also is a device that limits the change in current flow.
Barnstars:
“ 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”
For this case there are devices called Metal oxide varistors (MOV).
2024–10–10[John johnson John Johnson ]
2024–10–11 [Bobby Sanchez Bobby Sanchez ].
It’s been three xxx five werks, and there has been no response to my follow on query on his Commment to my answer.
The MOV will conduct when the voltage exceeds 50% of line voltage.
What is lightning?
He then asserts :
nine
Here is a simplified AC power diagram.
Fuses, on their own, then operate much slower than the MOV variable resistance, during the lightning strike.
At one ohm, the resistor has a maximum of 1 watt power.
The third is lightning and “how it gets conducted into a home.”
There are two important concepts here.
Now when you have a certain ac resistance, then a current flows in a loop.
but this device (an Inductor) … impedes the rapid changes in the current.
Is the question then , "why buy a surge supressor, if the fuse alone protects the electronic circuits from a lightning bolt?".
[old diagram got deleted by accident]
But… the neutral is now “floating” because of the 1 ohm resistance.
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.
What does a fuse do?
So, it’s possible that these devices from Trip Lite have addition suppression devices, these ones seem to be sturdy.
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.”
This is where the MOV conducts again, and dissipated the energy.
It seems Mohan does not understand the difference between a comment and an Answer.
So, the voltage could go up to 500 volts, and the fuse will not open up.
2024–10–11 [Victor Olarewsju Victor Olarewaju ]
This one hit behind the barn.
but I think this circuit , shows a few more pieces.
These are simplified answers to the original question, and does not change anything I wrote above.
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 is no concept of polarity, in the loop because the current changes direction 100 to 120 times a second (power frequency).
But during the surge, the fuse will not blow if it is a longer duration and lower value )10 to 50%).
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.
This device then solves the entire problem.
the problem then depends on "how fast does the fuse operate?".
I post the exact comment here.