BEARWALL that has nothing to do with gaming.
Has anyone ever told you this before?
“Oh, it was no big deal. It was just a blown fuse. I replaced it, we’re good to go”
Just so you know, that saying is a test.
A lot of things in life are tests, and it can be hard to recognize it when one comes around.
This post is in the way of a public service message for those of you that aren’t all too sure what “a blown fuse” means, and don’t want to look stupid or ignorant when someone tells you this in the future.
From now on, instead of nodding your head and walking away feeling vaguely worried, I’m going to arm you with science so you know what they’re saying… and what pointed questions to ask.
A Firm Grounding
Here’s the deal. If you’re reading this, you’re plenty smart enough and educated enough to understand what a fuse is, and what it means. You might just need a frame of reference.
Don’t panic. This won’t get technical.
You know your electronics runs on a power source we call electricity.
There are lots of technical terms used when discussing electricity, how it’s measured, how to calculate volts and amps, etc.
You don’t need to know any of that to live your life.
What you need to know is, how does it make that iPod spin out music, and can my iPod electrocute me if I drop it in water?
Quick answer: No.
We can functionally describe electricity as being similar to water. Water that is unaffected by gravity… but that loves finding a path to the deep, dark underworld.
What do I mean?
Let’s look at how water functions.
Water, when flowing, pushes things in front of it. The force of water pushing on things in it’s path can be used to get work done. The stronger the flow (or current), the more it can push, the more it can do.
Electricity works much the same way.
Picture a flowing stream or babbling brook. If there is a building on the riverbank, and that building has a waterwheel dipping into the river’s current, the force of the flowing water pushes on the paddles that are at the bottom, moving them forward, turning the wheel so that the next paddle dips into the current, and the rotation of the wheel continues, forever and ever, amen, ’til the river rises and the cows come home.
That waterwheel rotates on a shaft, and the shaft goes into the building, and what you get is a turning shaft inside a big building, powered by the flow of water. You can then attach stuff like gears and things, linkages and doodads, and get working machinery… powered purely by water. Triphammers, mill wheels, saws and drills and all sorts of stuff can be powered in this way.
Well, electricity is the same exact thing.
Except… instead of electricity flowing as water does, pulled down by gravity following the lowest surface it can find, electricity is special water that flows wherever it can find a conductive surface to carry it into the ground.
Electricity always heads for the easiest, simplest, fastest connection to the deep earth it can find. It follows the path of least resistance.
What is a conductive surface? Well, it depends on how strong the current of the electricity is, really.
Things like metal and water can be great conductors. Electricity touching metal will go straight to wherever the metal is touching the ground at the best point.
Rubber and the air can both be very good insulators, blocking the flow of electricity dead in it’s tracks. Plastic is pretty good at that, too.
But the more power, the more force, the more oomph in the electricity, the more resistance (or insulation) the electricity can overcome.
At high enough levels, the electricity can even jump through the air, conducting through the air itself to get to the ground. We call that an arc, and that’s some serious high power fry your ass mojo.
Why, if there is enough current in the electricity, YOU can be a conductor! You are a lot more conductive than the air, by the way. A LOT more conductive than the air.
Let’s have a brief experiment to illustrate this point.
Say you take a metal knife, and you stick it in a wall outlet… the electricity will instantly see that if it flows through the metal knife, and then through your body, it can reach the ground through your knees where you’re touching it, and off it goes.
At this point, you will either get blasted away from the outlet because the electricity flowing through your body from your hand to your knees caused your muscles to spasm, OR you will get locked rigidly to that knife, taking the juice constantly, because your muscles all just convulsed and locked up.
This can be a fun experiment, because if your friend or loved one sees you there unmoving or unresponsive, they might run over to grab you and pull you away… and IF they are suddenly a better conductor (say they are in bare feet while you’re wearing jeans) than you are, now the electricity sees a BETTER conductive path of least resistance through them, and BOOM, they get zapped too.
Quick fun fact: In the Marines, when you’re going to work with electricity, we used to make safety devices. What these were, were long wooden sticks covered in rubber, with a metal hook screwed into one end and also covered with rubber. They were for when a Marine grabbed a live wire, convulsed, and you had to get them free without electricuting yourself. You could grab the 8′ long rubber-coated hook off the wall, and either hook them and drag them away or just whack them good with the rubber stick.
Oh no? Oh, hell yes.
Are you paying attention now?
Just to ease your worried mind, you should know that there are two kinds of electricity… direct current (DC) and alternating current (AC). The kind of electricity in your wall outlets and in your home is all AC, or alternating current. Think of it as special electricity that pulses instead of just staying strong and steady. It pulses so fast you wouldn’t notice it without special gear, but your muscles will know the difference, because if you get zapped by AC, the first pulse may lock your muscles up and cause them to contract but the next pulse will convulse you and blast you free.
Direct Current, now… that shit will lock you up, holmes.
Where do you mostly find DC (Direct Current)? Why you find it INSIDE a lot of pwoerful electronics like TVs, stereos, microwave ovens, motors, air conditioners, all that kind of stuff. AFTER where the AC power cord comes into the gizmo, goes through a transformer and some other stuffs, and gets distributed throughout the thingie as nice, smooth DC voltage.
THIS IS WHY YOU AREN’T SUPPOSED TO SCREW AROUND INSIDE ELECTRONICS WITHOUT TRAINING.
Electricity is like water, it pushes stuff in front of it. It is supposed to start at, say, a wall outlet or breaker box. Then it flows through a conductive material, like metal wire, that is covered in a insulating material like rubber to keep it IN the wire, goes into a gizmo, pushes stuff around inside the gizmo to make it move and get work done… and then, believe it or not, goes right back out a second insulated metal wire and back into the wall outlet, return to sender.
It makes a complete circuit.
This is why, if you look at an AC power cord, it is two wires, each wrapped in rubber to isolate them from each other. One is the supply of juice TO teh gizxmo, the other is the return pipe FROM teh gizmo. They are commonly called the ‘Hot” and the “Neutral”, respectively. The hot is usually coated with black rubber, and the neutral is coated with white, when found in American wiring diagrams or inside a junction box.
You often also find a third wire. It is colored green inside gizmos, and it is called the ground wire.
Why? Because the ground wire does NOT carry any juice at all. None. It is dead as a doornail… and it is there to save your life.
The ground wire is attached to the deepest, darkest pit of black underground wetness there is anywhere near your house. It is THE favorite path for current to flow.
The ground wire is plugged into your gear, fixed to metal parts like the case… and is supposed to be a safety. If the hot or the neutral gets cut or shorted, instead of you getting killed by touching the metal case of your stereo, the power goes through the case, to the ground wire, and down to that inky it of blackness where all electricity finds it’s home instead.
It also provides a wonderful way of making sure you don’t get outside sources of electricity, like static electricity, interfering within your delicate electronics like your Xbox 360. If you zap the case, the ground wire bleeds the electricity off to ground so it never zaps the guts of the machine.
But what about fuses, you idiot!
It is normal to put a fuse in the wire at different points.
Breakers in your electrical panel in your house are, essentially, fuses too.
What a fuse is, is a wire designed to melt at a certain temperature, enclosed in a VERY insulative holder. It’s just the same as wire, but if it gets too hot, it melts.
Fuses melt when they get too hot, and when that happens, no more path for the current to flow. Electricity stops flowing, because the wire just got cut. The gizmo stops working… because the electricity HAS to flow for it to push or otherwise make the gizmo do stuff.
So, if a fuse is designed to melt when it gets too hot, what causes it to heat up?
More specifically, the amperage in the electricity.
What is amperage?
You don’t need to know exactly what it is, but it can help to think of it like this.
Now, this is completely and totally wrong, and yet it may help. Professionals, if you think I’ve taken liberties before this, hold onto your hats. It’s all in a good cause.
When you see a sign saying # of volts, # of amps, think of it like this.
The amount of volts is the size of pipe the electricity is traveling in. The more volts, the bigger the flow of electricity can be, the more work it COULD do.
The amount of amps is the actual POWER, the push, the big honking wave that is flowing through the pipe, doing the actual work.
To complete this horrible analogy, the stuff that the electricity is pushing in whatever gizmo you’ve got? That is the resistance. The more it resists the amps trying to push it, the more amps you need to provide to get it to go.
Here is why you should care.
You could have 480 volts on the line, a huge pipe. But if there are only .2 milliamps in the circuit, an itty bitty amount of current, you can grab the bare wire in your hand and only feel a tickle.
If you lick a 9 volt battery, getting your tongue on both prongs at once and feel the electricity flow across your taste buds from one pole to another, it won’t blow your ass up because the amps are very low.
But if you grabbed that same 480 volt wire, and there were 20 or more amps on there… if those 20 amps of force decided to flow through YOU as the fastest way to get to the ground, if YOU became the “path of current flow”, then you can die, cooked from the inside out, with your feet blown off and still steaming in your boots.
I’m not kidding around here.
What makes a fuse melt?
Amps of force performing work, pushing through things that offer resistance, generate heat.
If there is too little wire to handle all the amps flowing through it, that wire will, literally, melt.
The reason you have circuit breakers in your house is to prevent you plugging in too many things on one circuit or loop of wire, drawing a SHOTLOAD of amps through the wires in the walls of your house to power all that crap, melting the wires buried in your walls and setting your house on fire.
The circuit breaker is a fuse, designed to trip out or ‘break’ when it gets too hot… and capable of being reset. It trips when there are more amps flowing through it than the wires attached to it are capable of handling.
Circuit breakers are designed to be reset, on the assumption you know enough to unplug stuff from the appropriate outlet when one pops. Old school power panels had actual fuses that you had to replace… and many skilled and brilliant electricians would replace them, all right. With copper pennies. Sigh.
So, pop quiz because you know the answer now. What does a blown fuse mean?
It means that something got so hot it melted a piece of wire. It melted a piece of wire that was designed to melt for a reason; to protect something else from getting damaged from too much force/amps/electricity/power.
So now we come to the main event.
If a fuse blew, it didn’t do it out of spite, or vindictiveness.
That fuse blew because something somewhere else went wrong, and the fuse melted to protect your valuable shit, or even your life.
Why your life?
Because the most common place to stick a fuse is right where the wire comes into your gizmo from the power cord plugged into the wall. If that fuse melted, something somewhere in your gizmo suddenly decided to suck so much juice out of the wall it melted a wire… melted that wire before it melted something else. Or tripped a breaker in your power panel.
Or shorted right through you, blowing off your feet.
So if someone says to you, “Oh, it was no big deal. It was just a blown fuse. I replaced it, we’re good to go”, the very next question you need to ask is, “What caused the fuse to blow?”
That is the test.
To know that a blown fuse is not the problem, a blown fuse PROTECTED you from the problem.
What caused the fuse to blow? Because if all you did was replace the fuse, what the hell is stopping whatever it was from causing it to blow again?
What if the reason the fuse blew, was that there is water somewhere inside the gizmo. Electricity likes to find the easiest path to ground, right? And water makes for a good conductor. the electricity doesn’t want to do work, it doesn’t want to flow through any resistance, it’s always looking for the easiest way out.
So there is water, and sometimes the gizmo moves, the water flows, touches somewhere that has electricity, and the electricity says “Ah HAH! I can bypass almost all this other shit, flow right through the water, take a shortcut, and go through this here control knob, through that person’s hand, down their arm, and ground myself on the metal arm of the chair. YAHOO! FREEDOM AT LAST!”
Or maybe, and god this is common, maybe you’ve got a motor that is powered by electricity in your gizmo. Like your car. Or your air conditioner. The motor is physically moving, spinning round, from the force of electricity pushing it.
It takes a lot of amps to physically move a motor. Lots more than your iPod needs. Rule of thumb, if the electricity has to get a motor physically moving, it’s got a LOT of juice running through it. Moving parts take power.
The motor has all this power running through it, some insulation starts wearing away, or the bearing that lets the shaft turn nice and smooth starts binding up making the motor use a LOT more power to get that shaft to turn, and the heat from the increased amp draw builds up.
The fuse blows. It gets hot and melts, protecting your motor from turning into slag.
If this is caught right away, the motor can usually be fixed. Maybe by something as simple and easy as putting a bit of grease or oil on the bearing that the shaft turns on, reducing how hard the motor has to work.
But what do I see all the damn time?
“Fuse blew, I replaced it and got the device back in service.”
“What caused it to blow?”
“I dunno, probably just a power spike.”
“Nothing else went down, and the lights didn’t flicker. Go check it out, find out why it blew.”
“Okay.” *very grumpy*
A week passes.
The motor ‘burns out’, from too much heat because instead of greasing the motor bearings, the jackass replaced the fuses and didn’t ‘waste his time ‘troubleshooting the core problem.
I look inside at the fuses, wondering why the $20 fuses did not pop, protecting the $3000 motor from melting by blowing first, like they were designed to.
I see that the fuses, which are supposed to blow if the electrical current flow exceeds 20 amps, have been replaced by 30 amp fuses.
It takes a lot more heat to blow a 30 amp rated fuse than a 20 amp rated fuse. If the amps never rise above 30 amps, the wire inside will never heat up enough to melt.
But that motor sure did love the extra amps that drove it far harder than it was ever designed to, at a temperature it’s wires weren’t designed to handle. Wires melted, or maybe even the motor windings.
Meltdown. $3000 motor burnt to shit. Repairs and rewinding will probably cost about $1200.
Oh wow, but at least those $20 fuses are still in great shape, and the tech that decided to swap 20 amp fuses for 30 amp fuses so he wouldn’t have to keep replacing them when they blew over and over?
Well, at least he had some piece and quiet for that week.
Wrapping this up
Now you know what a blown fuse really means. It means more juice, more power, more amps, more OOMPH just went through the thing than it was designed to safely handle, and the fuse blew before something SERIOUS happened. Read: expensive or dangerous.
If you simply replace the fuse, you are giving whatever it was a chance to do it again, shocking the system and risking damage from the fuse melting too SLOWLY to stop the big jolt of power from going through and doing it’s damage to the sensitive guts of your gear first.
If you replace the fuse with a BIGGER fuse, what you’re doing is saying, “I don’t like to live safely, or to save money. Fuck it, let the motor burn, just as long as it stops bugging me by popping all the time.”
Yes, a spike of power from the source can cause a fuse to blow or breaker to pop. A lightning strike on the main supply coming into your house, etc.
But if it did… you should have seen lights flicker, or had some other indication than just one thing popping a fuse.
At the very least, I hope that now you will feel confident whenever you are talking to someone about your car, or stereo, or air conditioner, or circuit breaker, to call them on the carpet if they feed you that old “It was just a fuse” line.
Today, it was just a fuse. Tomorrow, it’s the water pump, or the fan motor, or the overhead crane drive, or whatever it may be.
Or something compound in your car. I don’t care what it is, if it’s compound, it’s money.
This may not have helped you, but by God I’m glad to get that off my chest. Freaking idiot techs, I swear I’m going to start using the Big Safety Stick™ to give them a current test they won’t soon forget..