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: 18.06.2025 00:52

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.
Can the fuse protect the electronic devices from lightning instead of a surge protector.
What is lightning?
Why are Republican politicians so afraid to oppose Trump?
This is where this question deviates from being a 'generic' question, and becomes more specific.
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?
Is the question then , "why buy a surge supressor, if the fuse alone protects the electronic circuits from a lightning bolt?".
Do you regret being married to your current wife?
This one hit behind the barn.
What does a fuse do?
the problem then depends on "how fast does the fuse operate?".
Have you ever been a victim of gaslighting? What happened?
[old diagram got deleted by accident]
He then asserts :
In schematic diagrams this is the symbol for a fuse:
The third is lightning and “how it gets conducted into a home.”
P = e* I, so since I is 16 amps, then the voltage dropped is 1/16 volt or 0.0650 volts.
(Dc diagram shown, AC is similar).
This is 'the assistant's answer'
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.
Which bands became massively popular for covering songs rather than recording originals?
2024–10–10[John johnson John Johnson ]
There are two important concepts here.
The bolt then partially travels down the line to your home.
He then describes Rainy Season and Lightning.
The other is “what does a “fuse” do?”
So combined with a device called a MOV or Metal-oxide-resistor, then forms the 3rd part of a “surge suppressor “.
Can I use the LEG PRESS to build muscle?
Edit 2024–10.
but this device (an Inductor) … impedes the rapid changes in the current.
So, the voltage could go up to 500 volts, and the fuse will not open up.
Doctors Say You Might Be Eating Way Too Much Salt — Here’s How To Tell - BuzzFeed
“ … to protect building, lightning arrestor, is provided above building and directly connected to earth.”
Upvotes:
For this case there are devices called Metal oxide varistors (MOV).
5 Simple Walking Tricks That Burn Fat and Build Muscle, According to a Trainer - Eat This Not That
I post the exact comment here.
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 is the picture of an electronic coil of wire wound around a core of magnetic material.
What are the best self-care practices to improve mental health?
Mohan forgets that a fuse is a one-time device, and needs to be replaced if it is tripped.
When the current is 200% of the rated value , it will “go open” (the link metal melts) and protect the device.
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.
Would you let your partner cheat on you every now and again?
These devices are installed between the “hot” and “neutral” and protective ground.
Would individual surge supressors have save this equipment? most likely, since the surge supressor would take the jolt instead of the electronic components.
At one ohm, the resistor has a maximum of 1 watt power.
What are the 10 things you regret doing in your life?
2024–10–00 [ Ammar Mahdi ] Ammar Mahdi
“ 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”
2024–10–14 [Omar Gharbi Omar Gharbi ]
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.
(There is no concept of polarity, in the loop because the current changes direction 100 to 120 times a second (power frequency).
So, it’s possible that these devices from Trip Lite have addition suppression devices, these ones seem to be sturdy.
2024–10–16 [ OO OLAOYE OYEBODE ]
A circuit breaker is similar, but is resettable.
so, what happens?
Barnstars:
An AC voltage/ current source, and an ac inductive load.
what exactly is a ‘surge’ protector?
OK, this is Mohan Rajaratnam’s definition of a Surge suppressor.
Because the load is inductive, the current lags the voltage.(by a bit).
But it can get overloaded, and no longer works.
But… the neutral is now “floating” because of the 1 ohm resistance.
One is “what exactly is in a ‘surge protector’ ? ”
But during the surge, the fuse will not blow if it is a longer duration and lower value )10 to 50%).
2024–10–11 [Bobby Sanchez Bobby Sanchez ].
Now when you have a certain ac resistance, then a current flows in a loop.
A fuse is a non-resetable over current circuit 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 photo is worth a thousand words.
One
“ A fuse is a device which protects the (circuit) against overload and short circuit.”
eight
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 are three different concepts here that are getting confused.
so, the loop of wire then, when put together with another loop reduces the ‘noise’ on a power line.
but I think this circuit , shows a few more pieces.
This device then solves the entire problem.
The MOV will conduct when the voltage exceeds 50% of line voltage.
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.
2024–10–11 [Victor Olarewsju Victor Olarewaju ]
It seems Mohan does not understand the difference between a comment and an Answer.
Fuses, on their own, then operate much slower than the MOV variable resistance, during the lightning strike.
He then describes the function of a fuse.
nine
At least they know the answer if they wanted it.
This is where the MOV conducts again, and dissipated the energy.
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.
[image of Common-mode choke]
First Sentence:
These are simplified answers to the original question, and does not change anything I wrote above.
Here is a simplified AC power diagram.
It also is a device that limits the change in current flow.