Should you unplug chargers when you're not using them - tested

[jcdeboever]

I can only hope that someday science will finally truly understand how electricity works.

Can't see it

Sent from my XT1254 using Tapatalk

 

[480sparky]

I can only hope that someday science will finally truly understand how electricity works.

Here's how it works :

Person either has an electrical problem, wishes to modify their existing system or have the need for an entirely new installation. They call me. I do the work. When I'm done, they write a check or whip out the plastic. I put money into bank and we're both happy.

That's good 'nuff fer me.

 

[runnah]

I can only hope that someday science will finally truly understand how electricity works.

Here's how it works :

Person either has an electrical problem, wishes to modify their existing system or have the need for an entirely new installation. They call me. I do the work. When I'm done, they write a check or whip out the plastic. I put money into bank and we're both happy.

That's good 'nuff fer me.

I hail to thee o mighty wizard!

 

[astroNikon]

I hail to thee o mighty wizard!

Mighty "Electrical" Wizard !!

yeah, shocking eh ?

pun intended

 

[Scatterbrained]

I'm not saying it's the most efficient way to do it. It's just the way it's done at present.

Think about your car. It has an alternator. As long as the car is running, the alternator is turning and making electricity. Along with supplying all the electrical power needed to operate the various electrical devices in the car, if the battery needs topped off again after using some of its energy to start the vehicle, it does that.

But once the battery is topped off again, does turning the lights, radio, AC and other non-essential equipment on or off affect how much the alternator is putting out? No, it just keeps putting out what it puts out, whether you need it or not. If you don't use it, it's just gone...

Noooooo... not quite. The car's voltage regulator (or PCM/EMU equivalent in new vehicles) controls the alternator output based on demand. The greater the demand, the greater the output. The greater the output, the greater the rotative resistance of the alternator due to the increased strength of the EM field. Thus, it is a fact that the more electrical load you place on your car's alternator, the lower your fuel economy.

This was one of the arguments used by people who were against the mandatory use of headlights during the day and/or daytime running lights. While it's true that using your headlights (or super-duper stereo, or whatever) will reduce fuel economy, the loss is very, very, very small, BUT... there is no "lost" electricity. Un-needed power is simply not there as it's never produced in the first place.

Actually, the voltage regulator maintains a constant 14v DC output from the alternator (yes, most modern 12v systems run around 13.8v). The point of ECM controlled alternators isn't to control amperage output, it's to control voltage level and ramp up. Modern automotive computer systems are robust in some ways, but rather delicate in others. The ECM gradually ramps up the field current from the battery to the alternator to slowly bring it up to it's proper working output, thus preventing a surge through the system. It also maintains a much closer control of the voltage level at the alternator. Modern alternators also have "clutches" on the alternator pulleys to keep the alternator spinning smoothly between "hits" from the engine. (each time a set of cylinders fire it creates a hit, or surge that is felt in the alternator). These things are done to control voltage however, not amperage.

 

[Scatterbrained]

I'm not saying it's the most efficient way to do it. It's just the way it's done at present.

Think about your car. It has an alternator. As long as the car is running, the alternator is turning and making electricity. Along with supplying all the electrical power needed to operate the various electrical devices in the car, if the battery needs topped off again after using some of its energy to start the vehicle, it does that.

But once the battery is topped off again, does turning the lights, radio, AC and other non-essential equipment on or off affect how much the alternator is putting out? No, it just keeps putting out what it puts out, whether you need it or not. If you don't use it, it's just gone...

Noooooo... not quite. The car's voltage regulator (or PCM/EMU equivalent in new vehicles) controls the alternator output based on demand. The greater the demand, the greater the output. The greater the output, the greater the rotative resistance of the alternator due to the increased strength of the EM field. Thus, it is a fact that the more electrical load you place on your car's alternator, the lower your fuel economy.

This was one of the arguments used by people who were against the mandatory use of headlights during the day and/or daytime running lights. While it's true that using your headlights (or super-duper stereo, or whatever) will reduce fuel economy, the loss is very, very, very small, BUT... there is no "lost" electricity. Un-needed power is simply not there as it's never produced in the first place.

Noooooo... not quite.

The regulator turns the alternator on or off based on the voltage coming out of the battery. All the electronics run off the battery, hence why you turn the batter on and use the radio while the car is off. The regulator's jobs is to "sense" when the voltage coming out of the battery dips below a certain amount, normally under 13.5 volts. When it dips below the regulator say "oh ****, we need more magic pixies to refill the battery!" and it turns on the alternator and recharges the battery to the 14.5 or so volts. The alternator generates the same amount of AC current any time it's on.

No different than a shop air compressor. Set it to xyz PSI, do some wrenching, drop the pressure and the motor kicks on to fill up the tank again. The air gets filled up at the same rate no matter how empty or full the tank is.

The alternator never "shuts off". It's on whenever the car is running. As Buckster pointed out, you don't need a battery for anything but to start your car. If you'r drawing down the battery while driving you've got an issue somewhere (or you've installed more additional electronics than your alternator is rated for). You turn the ignition key to the Acc. position to listen to the radio when the car isn't on yes. Of course it's pulling from the battery. When the engine isn't turning the alternator isn't turning either, meaning there is no way for it to generate electricity. This makes the cars battery the only source of power.

 

[runnah]

Noooooo... not quite.

The regulator turns the alternator on or off based on the voltage coming out of the battery. All the electronics run off the battery, hence why you turn the batter on and use the radio while the car is off. The regulator's jobs is to "sense" when the voltage coming out of the battery dips below a certain amount, normally under 13.5 volts. When it dips below the regulator say "oh ****, we need more magic pixies to refill the battery!" and it turns on the alternator and recharges the battery to the 14.5 or so volts. The alternator generates the same amount of AC current any time it's on.

No different than a shop air compressor. Set it to xyz PSI, do some wrenching, drop the pressure and the motor kicks on to fill up the tank again. The air gets filled up at the same rate no matter how empty or full the tank is.

Okay, I freely admit that while I'm a decent shade-tree mechanic, the electrical system is very definitely my weak area. That said, based on my understanding, I think you might be confusing voltage and current. Yes, the voltage is constant (more or less), but the current varies according to demand. Voltage is analgous to pressure, current to volume, in your air compressor analogy, it always produces 100psi, but will vary between 10 and 20 CFM, depending on load.

The primary functions of the battery in a car are (1) to provide initial power for the starter motor; and (2) to provide the initial excitier or field voltage necessary for the alternator to work. Once the engine is running normally, the alternator becomes self-sustaining. Yes, you can run all of your accessories off of the battery, but that's a result of the parallel circuit design of the battery installation.

If your car is running during the day, with no lights, heater, AC, stereo, etc, then the load is pretty much only that required by the ignition system, let's say 5 amps (just picking a number out of the air). To produce that 5 amp output the alternator requires a 1 amp exciter current. This is all done at (about) 13.5 volts, but if all of a sudden you turn on the lights, the AC, and the 8,000,000 watt bass-boosted stereo in the trunk, the demand might jump from 5 to 85 amps. That 85 amp output requires, let's say a 10 amp exciter current, as the exciter and output currents rise, the strength of the EM field in the alternator increases and with it, the resistance in the alternator, hence the reduction in fuel economy as load/demand increases. <-- As I said, that's my understanding. I was wrong once before, it could happen again...

No you're right, not sure where I got voltage from.

 

[Ricguch]

Ok, i have been lurking the forum and for this i have to signup finally,

power plants produce way more power than is used, but if we start consuming more they have a power level limit,if we get close to that limit they start producing more, also the otehr way around if suddenly we drop the power we are using a lot they can start dropping the power production. So if all of us save power it makes a difference, just one person it does not

Now, car alternator, if its spinning is producing power, i dont know if newer cars can disangage the alternator, as far as i know, it can control how much goes into the battery, so it doesnt overcharge.

Sorry for broken english

 

[KmH]

I can only hope that someday science will finally truly understand how electricity works.

Maxwell's equations - Wikipedia, the free encyclopedia

 

[waday]

I can only hope that someday science will finally truly understand how electricity works.

Maxwell's equations - Wikipedia, the free encyclopedia

Not sure about anyone else, but I seem to be governed by Murphy's Laws.

 

[Didereaux]

Personally I unplug all chargers and unnecessary devices when I am done with them Why? Because they are all plugged into 120AC, and any device can short out causing a fire. Why take the chance?

 

[RitchieE24]

Istead of worrying about 34¢ of electricity being used by a plugged-in phone charger, why not offset that by installing just ONE single CFL or LED lamp in your house or office?

That's what I am in the middle of doing. I recently purchased 5 Sylvania LED bulbs from Canadian Tire for $2 a piece. They were in a clearance bin for $7.00 but I used the "SaveOnEnergy" coupon for $5 off each bulb. Thanks Ontario Provincial government!

 

[Didereaux]

Personally I unplug all chargers and unnecessary devices when I am done with them Why? Because they are all plugged into 120AC, and any device can short out causing a fire. Why take the chance?

Someone disagreed, but gave no reason. I wonder if he disagreed that they plugged into 120AC, or that any such device can short out. Either one is provably true, and so the disagreeing person looks rather ridiculous.

 

[tirediron]

Someone disagreed, but gave no reason. I wonder if he disagreed that they plugged into 120AC, or that any such device can short out. Either one is provably true, and so the disagreeing person looks rather ridiculous.

Let's try and remember that the 'Disagree' button is no different in concept than the 'Agree' button; simply an expression of concurrence or non-concurrence of a statement made by someone else. Please do not take it personally, and like agreements where there is often no reason given, there is none required for a disagreement.

 

[charchri4]

Considering the millions of street lights pointlessly lighting empty streets and the yard of light every farm house in the country lighting an empty yard, I have a hard time getting excited about this.