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Laptop and mains power

S

sinecurea

macrumors regular
Original poster
Mar 14, 2006
127
0
Northern Ireland
Hi Folks,
I'll get straight to the point: Is there any harm in using a Mac Laptop with the power chord plugged in a lot of the time?

I've just got a MacBook Pro, and I use it a lot of the time near a plower plug, so I naturally plug it in to stop the battery level from dropping and accelerating the natural life of the battery. When the light turns green, does the power stop going to the battary or what exactly happens?

Any opinions?

Cheers,
Steve.
 
Simply put, no. I do that with my PowerBook. If it is constantly plugged in though, it is a good idea to fully drain the battery once every few weeks or so. When the light goes green, the battery is charged, and the computer is running off the wall adapter.
 
So, unpredictible freak power-failure entity aside, when I plug the laptop into the wall, it completely bypasses the battery? - I'm presuming then that I would be able to use the laptop from the power source with the battery removed then.

Questions:
1) May I therefore assume that I will prolong the power of my battery by keeping the power lead plugged in when I am near a socket.

2) Can anybody verify this information from the advice of an expert in laptops and/or batterys/power suppllies?

Cheers!
Steve.
 
I'm not going to keep it plugged in 100% of time, I do like using it away from a power point, so I'm going to keep with Apple's "we don't recommend keeping the laptop plugged in all the time" theory. I just don't see the point in using the battery when there's a perfectly good power supply there. At the same time, I'm basically looking to know if there's any problem with keep it in power most of the time.

Cheers,
S.
 
sinecurea said:
So, unpredictible freak power-failure entity aside, when I plug the laptop into the wall, it completely bypasses the battery? - I'm presuming then that I would be able to use the laptop from the power source with the battery removed then.

Questions:
1) May I therefore assume that I will prolong the power of my battery by keeping the power lead plugged in when I am near a socket.

2) Can anybody verify this information from the advice of an expert in laptops and/or batterys/power suppllies?

Cheers!
Steve.
Click to expand...

Hey Steve,

I'm no expert, but I have a powerbook and have read tons of posts on this subject on macrumors.

1) Yes, but you should calibrate it everyone once in awhile.

2) Apple's Calibration Page

Apple's Battery Tips

One of many posts on this.

EDIT: And enjoy that MBP!
 
i avoid plugging in my mbp too much because im afraid itll mess up my battery. one time i plugged in my laptop but, because i didnt want to screw up the battery, took out the battery while the laptop was plugged in. bad choice. the magsafe isnt strong enough to do this. the magsafe popped out and i lost all my work.
 
sinecurea said:
Hi Folks,
I'll get straight to the point: Is there any harm in using a Mac Laptop with the power chord plugged in a lot of the time?
Click to expand...

No harm.

The computer contains a circuit that controls the charging of the battery. This circuit ensures that once the battery is fully charged then a reduced current is sent to the battery to keep it fully charged but ensuring that the battery is not harmed by the constant power source.

Batteries used in modern powerbooks wear out over time in proportion to their discharge use. After a period of time, a battery that is always run down to zero will hold a less of a charge than a battery that is only run down a little bit before being recharged.

If you run your battery down to 80% charged and then charge it back up, then 5 of these cycles (5* 20) roughly equals one discharge cycle. The more discharge cycles the lower the battery life.

Personally, I tend to keep my powerbook connected to the power adapter about 90% of the time I use it. I have a power adapter at work, and another under the sofa at home. The powerbook is turned on for at least the 8 hours I spend at work each day, together with 2-5 hours of use of a night and on each weekend day. After 20 months of this type of use I can still easily get 3.5 hours of battery time. My max charge is now 97.6% of a new battery.
 
I've had my titanium plugged in for the past 4 years. I rarely take my laptop anywhere and use it primarily as a desktop machine. No problems.
 
jsw123 said:
i avoid plugging in my mbp too much because im afraid itll mess up my battery. one time i plugged in my laptop but, because i didnt want to screw up the battery, took out the battery while the laptop was plugged in. bad choice. the magsafe isnt strong enough to do this. the magsafe popped out and i lost all my work.
Click to expand...

how could it just pop out? i dont understand?
 
I might just be naive, but I would rather not worry about recalibrating, and charging on a schedule, and just use it as you need it. I have 2 year old a 12inch powerbook that gets used as needed (battery wise) still has 2-3 hour charge. If it ever went down I'd just buy a new battery. I equate that cost to the cost of loosing my mind making sure I am treating it correctly at all times. just MO. ;)
 
Is the battery a P/S component?

...as with Steve, I would also like to know what happens when the power plug indicator turns green ...does the power supply circuit still use the battery as a filter capacitor or regulator component?

...also in relation to this (i.e. is the battery a P/S component), is it safe to use the MBP on power supply alone (i.e. with battery removed altogether)? ...apart from the obvious risks of mains supply fluctuations, failures, spikes, brownouts, etc., and/or the power plug physically disconnecting from the laptop or wall socket.

Thanks

Xain
 
...as with Steve, I would also like to know what happens when the power plug indicator turns green ...does the power supply circuit still use the battery as a filter capacitor or regulator component?

...also in relation to this (i.e. is the battery a P/S component), is it safe to use the MBP on power supply alone (i.e. with battery removed altogether)? ...apart from the obvious risks of mains supply fluctuations, failures, spikes, brownouts, etc., and/or the power plug physically disconnecting from the laptop or wall socket.

Thanks

Xain



Hi Folks,
I'll get straight to the point: Is there any harm in using a Mac Laptop with the power chord plugged in a lot of the time?

I've just got a MacBook Pro, and I use it a lot of the time near a plower plug, so I naturally plug it in to stop the battery level from dropping and accelerating the natural life of the battery. When the light turns green, does the power stop going to the battary or what exactly happens?

Any opinions?

Cheers,
Steve.
 
Is the battery a P/S component?

...as with Steve, I would also like to know what happens when the power plug indicator turns green ...does the power supply circuit still use the battery as a filter capacitor or regulator component?

...also in relation to this (i.e. is the battery a P/S component), is it safe to use the MBP on power supply alone (i.e. with battery removed altogether)? ...apart from the obvious risks of mains supply fluctuations, failures, spikes, brownouts, etc., and/or the power plug physically disconnecting from the laptop or wall socket.

Thanks

Xain



Hi Folks,
I'll get straight to the point: Is there any harm in using a Mac Laptop with the power chord plugged in a lot of the time?

I've just got a MacBook Pro, and I use it a lot of the time near a plower plug, so I naturally plug it in to stop the battery level from dropping and accelerating the natural life of the battery. When the light turns green, does the power stop going to the battary or what exactly happens?

Any opinions?

Cheers,
Steve.
 
...as with Steve, I would also like to know what happens when the power plug indicator turns green ...does the power supply circuit still use the battery as a filter capacitor or regulator component?

...also in relation to this (i.e. is the battery a P/S component), is it safe to use the MBP on power supply alone (i.e. with battery removed altogether)? ...apart from the obvious risks of mains supply fluctuations, failures, spikes, brownouts, etc., and/or the power plug physically disconnecting from the laptop or wall socket.

Thanks

Xain



Hi Folks,
I'll get straight to the point: Is there any harm in using a Mac Laptop with the power chord plugged in a lot of the time?

I've just got a MacBook Pro, and I use it a lot of the time near a plower plug, so I naturally plug it in to stop the battery level from dropping and accelerating the natural life of the battery. When the light turns green, does the power stop going to the battary or what exactly happens?

Any opinions?

Cheers,
Steve.
 
...as with Steve, I would also like to know what happens when the power plug indicator turns green ...does the power supply circuit still use the battery as a filter capacitor or regulator component?

...also in relation to this (i.e. is the battery a P/S component), is it safe to use the MBP on power supply alone (i.e. with battery removed altogether)? ...apart from the obvious risks of mains supply fluctuations, failures, spikes, brownouts, etc., and/or the power plug physically disconnecting from the laptop or wall socket.

Thanks

Xain



Hi Folks,
I'll get straight to the point: Is there any harm in using a Mac Laptop with the power chord plugged in a lot of the time?

I've just got a MacBook Pro, and I use it a lot of the time near a plower plug, so I naturally plug it in to stop the battery level from dropping and accelerating the natural life of the battery. When the light turns green, does the power stop going to the battary or what exactly happens?

Any opinions?

Cheers,
Steve.
 
...as with Steve, I would also like to know what happens when the power plug indicator turns green ...does the power supply circuit still use the battery as a filter capacitor or regulator component?

...also in relation to this (i.e. is the battery a P/S component), is it safe to use the MBP on power supply alone (i.e. with battery removed altogether)? ...apart from the obvious risks of mains supply fluctuations, failures, spikes, brownouts, etc., and/or the power plug physically disconnecting from the laptop or wall socket.

Thanks

Xain



Hi Folks,
I'll get straight to the point: Is there any harm in using a Mac Laptop with the power chord plugged in a lot of the time?

I've just got a MacBook Pro, and I use it a lot of the time near a plower plug, so I naturally plug it in to stop the battery level from dropping and accelerating the natural life of the battery. When the light turns green, does the power stop going to the battary or what exactly happens?

Any opinions?

Cheers,
Steve.
 
Xain said:
...as with Steve, I would also like to know what happens when the power plug indicator turns green ...does the power supply circuit still use the battery as a filter capacitor or regulator component?
Click to expand...

When the indicator turns green the battery has switched to "trickle charge". This means that a reduced current is passed to the battery to simply maintain the battery charge at maximum.

Xain said:
...also in relation to this (i.e. is the battery a P/S component), is it safe to use the MBP on power supply alone (i.e. with battery removed altogether)?
Click to expand...

No, this is not safe. With previous Apple laptops (eg Powerbooks, iBooks and earlier) it was possible to run them safely on mains power with the battery removed. With the MacBook and MacBook Pro machines when the battery is removed the CPU goes into a state that Intel has warned may damage your CPU. Further information: http://www.increw.com/the_news/latest_news/dont_run_your_macbook_without_batteries.html
 
apologies MKII

...I jumped the gun and assumed the LATEST post was at the top, so it seems that, at least in part, my questions have been answered. Now I know, it won't happen again (either FU)!! :(
 
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