External Battery Pack Option

[bjornb]

Yes, the MS RT charger works on the Pro, but the current limiting happens in the Pro, not the charger. The center pin in the connector is used by the Surface to identify the charger.

A quote from a different thread about chargers:

The center pin is called detect, from ifixit teardown step 17:
Microsoft Surface Pro Teardown - Page 3 - iFixit
I have the RT charger which I cut and used to create a cable for my external battery.
I did some tests as well, and found out that the Pro use the blue detect line (center pin) to identify the charger. If you connect the RT 2A charger to the Pro with the center pin masked/disconnected the Surface Pro will try to draw more than 2A (and the charger shuts down).

 

[Russ]

Yes, the MS RT charger works on the Pro, but the current limiting happens in the Pro, not the charger. The center pin in the connector is used by the Surface to identify the charger.

Bjornb --

Thanks for the correction. I got outside of my job description.

Take care,
Russ

 

[kcsims]

I will check back in a few days to see how the pro car charger works. I have also tried the bluetooth built into our car, but the audio delay between the devices is too annoying. I hope using the car charger wont have the same issue as the inverter.

 

[Wayne Orwig]

Yes, the MS RT charger works on the Pro, but the current limiting happens in the Pro, not the charger. The center pin in the connector is used by the Surface to identify the charger.

A quote from a different thread about chargers:

Yes. It would be difficult (not impossible though) to limit the current at the source (power supply). It is much easier to limit it where it is consumed, inside the tablet.

If that 'detect' pin really works like that, that would be the way to get the auto charger to work.

 

[kenman345]

Hey, I'm new here and hat a question about this charger.

It seems that you guys say it works for the Surface and I should expect to double-triple my battery life with the battery pack (26,000mAh) on my Surface Pro.

I also see that the external battery has a toggle switch for three Voltage settings, and I believe 12V's is the right one. Before I order, I'd like to know exactly how I am to use it properly. If someone can confirm the Voltage setting it would be much appreciated.

 

[Wayne Orwig]

Hey, I'm new here and hat a question about this charger.

It seems that you guys say it works for the Surface and I should expect to double-triple my battery life with the battery pack (26,000mAh) on my Surface Pro.

I also see that the external battery has a toggle switch for three Voltage settings, and I believe 12V's is the right one. Before I order, I'd like to know exactly how I am to use it properly. If someone can confirm the Voltage setting it would be much appreciated.

12 volts.

I put a drop of hot melt glue in the switch to keep it there.

 

[kenman345]

12 volts.

I put a drop of hot melt glue in the switch to keep it there.

That's what I was thinking of doing. Thanks for the help

 

[Russ]

That's what I was asking; has anyone used the Pro car charger yet?

Kcsims --

As promised, film at Eleven, almost.

I received my two chargers yesterday, as expected. I have not "used" them, but I did some testing on one of them today. I tested it in one of my cars (can provide car specs if needed). Here are the results: (this is from an email that I just sent to Mike at mikegyver.com:

"Engine off:
Direct reading: 12.57V ±
Adapter: 12.47V ±

Engine running:
Direct: 14.23V ±
Adapter: 13.97-14.15V

I am concerned about the 14V output from the adapter with the engine running, since the most common use would be while driving. I'm not sure if the Surface Pro will handle a 14V input. It does no good to ask Microsoft, since they will not respond to any questions involving third-party equipment."

Edited to add charger specs, as printed on the device:
Model 48W
Input: DC 12-16V max 10A
Output: 12V, 4A Continuous (well, not hardly)

If Wayne is around, I would really appreciate his comments on this.

I hope to hear from mikegyver.com tomorrow. Will post his reply. -- Evidently, Mike works on Sunday. Just received his reply:

"Hi Russ,

We've tested up to 15.5v constant on our bench on our surface Pro and have not had any problems and we feel that 14.15v should not be a problem.

Since we just entered in the market for the Surface Pro, we cannot give you any long term results, however based on our track record with the Macbook Air, which is 14.5v, we've tested on a long term bases at 16.5v and it has not had any problems. In fact, even apple "genius" bar plugs in an 16.5v adapter into the Macbook Air, which is normally 14.5v.

I know, not quite apples to oranges, but If this is a still concern to you, you may still refund if you wish.

Thanks,
Mike
Mikegyver.com"

Meanwhile, I'm gonna think about it. Maybe I'll wait until Ladyfriend returns from her trip and hook it up to her Pro. Yeah, there's a thought.

Regards,
Russ

 

[Wayne Orwig]

I did a little testing on my Surface Pro. It is of course switcher supplies. So that means it is all about wattage. When I ran it under 12 volts, the current went up. Over 12 volts and the current went down.
IMHO, under 12 is a problem. Current will rise, temperatures will rise. Over 12, current and temperature will likely drop, and it may run a bit cooler. At some point though, the voltage will of course over stress some parts. I suspect that I could run my Pro off of my power block with it switched to 18 V, and it would work well. But I'm not going to try it.
It is disappointing that they don't have better regulation on that power adapter. When you measured the voltage, did you have a load on it?

Sent from inside a tent in the rain on the Outer Banks using my Intocircuit as backup power.

 

[johnknee]

Has anyone purchased MCT's Surface cable (29.99) and connected to the Energizer XP18000A battery pack? Mike said as long the output is 12V and it has 5.5mm x 2.5mm male jack, it should work. Anyone can confirm this works?

 

[Russ]

When you measured the voltage, did you have a load on it?

Wayne --

Thanks for the info; I am encouraged.

No, I did not have a load on it when I measured. I don't have a good way of providing a load, except the Pro, and I wasn't ready to do that.

Regards,
Russ

 

[Russ]

Has anyone purchased MCT's Surface cable (29.99) and connected to the Energizer XP18000A battery pack? Mike said as long the output is 12V and it has 5.5mm x 2.5mm male jack, it should work. Anyone can confirm this works?

Johnknee --

I can definitely confirm that it works. I have done two external batteries: One was the XP18000A and the other was the Intocircuit 26000 Power Castle. The XP18000A comes with a bunch of various sizes of adapters. I didn't go through them all because I found what I needed in my box of unloved AC adapters, but there is probably one that will work. I would check for you, but the XP18000 is currently in Dubai. Here is a picture (slow load) of approximately what you are talking about: Energizer & Pro

I say "approximately," because at that time Mike was not offering his cable separately. I bought a cheapie car charger on Ebay just to get the cable, and spliced it onto the jack. I later bought a cable from Mike, and used it with the Intocircuit battery. Actually, I bought the Intocircuit battery for Ladyfriend to use on her Atlanta/Shanghai flight, but she decided to take the Energizer this time because it is lighter and she doesn't have that long single-leg flight.

Anyhow, I've done this a couple of times, and will be happy to answer any further questions.

Regards,
Russ