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mac000

macrumors 6502a
Original poster
Sep 6, 2005
679
0
I'm wondering what exactly that power cord that comes along with mbp is user for? Not the power brick, but the other power cord. I'm running my mbp in clamshell most of the time, so am i suppose to pop that battery out and use that 2nd power cord in addition to the power brick? -thanks
 

mkrishnan

Moderator emeritus
Jan 9, 2004
29,776
15
Grand Rapids, MI, USA
If you look at the place where the white brick of the power supply has the prongs to plug into the wall, you'll notice that this segment is removable. If you pull it out, you can replace it with the longer cable if you...erm... need a longer power cable. That's really about it. That, and it has a grounding prong in the US (whereas the little adapter doesn't).

EDIT: The part in the upper left of this picture is removable and gets replaced with that power cord.

MAC59247.gif


When you do this, it looks like this:

430079.jpg
 

mac000

macrumors 6502a
Original poster
Sep 6, 2005
679
0
If you look at the place where the white brick of the power supply has the prongs to plug into the wall, you'll notice that this segment is removable. If you pull it out, you can replace it with the longer cable if you...erm... need a longer power cable. That's really about it. That, and it has a grounding prong in the US (whereas the little adapter doesn't).

EDIT: The part in the upper left of this picture is removable and gets replaced with that power cord.

MAC59247.gif


When you do this, it looks like this:

430079.jpg


oh i see - so its just an extension.

Well to answer my other question, if im' not going anywhere with my mbp laptop am i suppose to pop the battery out while its just sitting there in clamshell? - im talking about it sitting there for days.
 

orangemacapple

macrumors 6502
Sep 1, 2006
442
0
Raleigh
Overkill

the airport express also uses the same brick design and power cord, but there is no power cord included with it. the cord from the power adapter fits it.

still can't figure out why it has a ground plug on the cord but not on the appliance. nor can i figure out why the extension cord is of such a heavy-duty design for no more power than it draws.
 

mkrishnan

Moderator emeritus
Jan 9, 2004
29,776
15
Grand Rapids, MI, USA
the airport express also uses the same brick design and power cord, but there is no power cord included with it. the cord from the power adapter fits it.

still can't figure out why it has a ground plug on the cord but not on the appliance. nor can i figure out why the extension cord is of such a heavy-duty design for no more power than it draws.

True... but it does come in handy sometimes. I have two iBook power supplies. One of them usually lives in my office for when I bring my iBook there. The other one has the long power cable on it and plugs into my iBook at home. The plug point itself is hard to access. But if I want to take it with me, I just unplug it at the brick and replace the short one.

*shrug* It's a bonus. You certainly need not *ever* use it if you do not wish to.
 

dornoforpyros

macrumors 68040
Oct 19, 2004
3,070
4
Calgary, AB
it's just an extension cord which I'm glad they include, I haven't even taken the plastic off the original attachment, I popped it off the brick, attached the extension cord and haven't removed it since. I suppose I might switch back when I fly tomorrow just so I'll have less crap in my laptop bag. But over all I'm glad it's there.
 

idea_hamster

macrumors 65816
Jul 11, 2003
1,096
1
NYC, or thereabouts
it's perfectly fine to leave the battery in all the time

Not only is it OK to leave the battery in all the time, it's my understanding that it is preferable to do so.

I think the battery acts as a buffer for variations in voltage that can affect performance, since the laptop does not have a full-blown power adapter like a desktop.

Of course, I don't have a reference, so this is just what I believe to be conventional wisdom. (Ergo, it could be pure weapons-grade bolongium....)
 

ravenvii

macrumors 604
Mar 17, 2004
7,585
493
Melenkurion Skyweir
Speaking of battery removal, I once foolishly removed my battery while my laptop was in sleep mode (I forgot it was on). D'oh! I put the battery back in, flipped the laptop, opened it up and sure enough it's off. BUT! When I hit the power button... it woke up from sleep!

Talk about cool!
 

idea_hamster

macrumors 65816
Jul 11, 2003
1,096
1
NYC, or thereabouts
Speaking of battery removal, I once foolishly removed my battery while my laptop was in sleep mode (I forgot it was on). D'oh! I put the battery back in, flipped the laptop, opened it up and sure enough it's off. BUT! When I hit the power button... it woke up from sleep!

Talk about cool!

True -- it seems that Mac (and possibly other) laptops are designed to allow a battery swap during sleep without shutting down.
 

MacsAttack

macrumors 6502a
Jul 2, 2006
825
0
Scotland
That extension came in real handy the other week. Plug in the hotel room was too close to the desk top to allow the brick to plug in (three pin UK plug - can the two-pin sockets be used wither way up????).

With the extension however I still had power and could recharge both my MacBook and my iPod :D
 

poppe

macrumors 68020
Apr 29, 2006
2,248
53
Woodland Hills
I have never found one moment yet since I got my Mac in November to acctually use the little piece that pops in the brick. Every single time I've tried I've found my self getting to far and the Mag safe popping out..
 

Silentwave

macrumors 68000
May 26, 2006
1,615
50
Not only is it OK to leave the battery in all the time, it's my understanding that it is preferable to do so.

I think the battery acts as a buffer for variations in voltage that can affect performance, since the laptop does not have a full-blown power adapter like a desktop.

This is true, and critical! Removing the battery locks the processor at its minimum speed of 1.0GHz!

Also, if possible, use the extension cord. It has a ground plug, unlike the flip one.
 

mkrishnan

Moderator emeritus
Jan 9, 2004
29,776
15
Grand Rapids, MI, USA
Since the AC adapter is capable of powering the computer going at full juice and charge the battery at the same time, I doubt removing the battery would somehow affect the power adapter's capacity ;)

Not to mention that, if the battery were being called upon to help supply power because there was not enough available power, then how could the notebook work for hours on end? :)

But anyway, others have reported it as a bug. It might just be some subtlety of Intel's power management that has not fully been correctly implemented in the OS X kernel extensions.
 

orangemacapple

macrumors 6502
Sep 1, 2006
442
0
Raleigh
Since the AC adapter is capable of powering the computer going at full juice and charge the battery at the same time, I doubt removing the battery would somehow affect the power adapter's capacity ;)

Probably some engineering decision though.


i don't think the ac adapter is powerful enough to power the machine and charge the battery. i can start with 100% and within a few minutes of moderate use, the battery reads 98% +/-. quit using the machine and it recharges to 100%. that says to me i need to get an 85 watt mbp supply for my mb.
 

orangemacapple

macrumors 6502
Sep 1, 2006
442
0
Raleigh
reason for ground plug

the reason for a grounding prong on the extension cord is SAFETY.
if some baby or pet started playing with the thing and slobbering all over it they might get electrocuted with the prong there. it's not an issue when the cube is plugged into the wall because it's much more difficult for a baby to slobber or spit-up on it there
 

Silentwave

macrumors 68000
May 26, 2006
1,615
50
does it limit the processor because of power demands?

Since the AC adapter is capable of powering the computer going at full juice and charge the battery at the same time, I doubt removing the battery would somehow affect the power adapter's capacity ;)

Probably some engineering decision though.

Not to mention that, if the battery were being called upon to help supply power because there was not enough available power, then how could the notebook work for hours on end? :)

But anyway, others have reported it as a bug. It might just be some subtlety of Intel's power management that has not fully been correctly implemented in the OS X kernel extensions.

Nope. Like idea_hamster said, it is a buffer for voltage variations that can damage the processor.
 

e12a

macrumors 68000
Oct 28, 2006
1,881
0
If you receive slight shocks from your MBP, try putting the three pronged cable on.
 

poppe

macrumors 68020
Apr 29, 2006
2,248
53
Woodland Hills
i don't think the ac adapter is powerful enough to power the machine and charge the battery. i can start with 100% and within a few minutes of moderate use, the battery reads 98% +/-. quit using the machine and it recharges to 100%. that says to me i need to get an 85 watt mbp supply for my mb.

I think this is incorrect. I constantly run my battery dry at class. Then come back home and start editing with FCP and almost the same charge times as when it is asleep it is completely charged..
 
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