Surface 3 Charging
- Thread starter GreyFox7
- Start date
Not necessarily but we will find out.
Your other devices may typically charge from a 5W 1A charger and the charger you have may be supplying up to 50W across multiple ports but only 2.4A 12W per port. However the device may only draw 1.5A 7.5W total and charge 1.5x faster.
The issue may be that we cannot exceed the current limit of the micro USB connector. The Qualcomm Quick Charge devices increase the voltage to 9v @ 1.5A or 12v @ 1.5A vs 5v @ 1.5A in standard USB but it only works on devices designed to operate with the higher voltages.
If you delve into it that charger's rating is probably with multiple ports /devices charging, somewhere it will tell you what the maximum single port rating is and I'd bet it's 3-4 amp; 15-20 watt. That would still be very quick for most devices.
The issue could have been avoided if they had used the Type C connector with higher power capabilities and supplied adapters for other chargers. MS said they changed to micro USB by customer demand.
Sometimes the customer is Wrong!
To all customers: Demand Type C on all future devices.
Sometimes the customer is Wrong!
To all customers: Demand Type C on all future devices.
Please keep in mind, that the charger you use is only half the story. The cable you use will allow/not allow you to use the full capabilities of the charger. There are a lot of crap cables out there. I have one that you would think would work great, but it will only pass less than 1A through it. I recommend a minimum of 24 AWG for power/ground and 28AWG for signal.
I think the other half of the story is most likely battery heat dissipation. Everything is limited by something, most times for a reason. With no fans or vent holes, quick charging generates a lot of heat, which is arguably a battery's greatest enemy. So far the charging rate hasn't caused me any problems that aren't offset by the advantage of using the same cables, chargers, and external batteries that I use for other portable devices.
I have tied a couple different cables so far and got the same results including using the supplied cable from Microsoft. Still haven't heard back from Limefuel regarding my query.
Testing continues... breaking out the USB power meter for further analysis.
Test using the MS Charger with MS cable, USB power meter inline, Batterybar monitoring internal battery.
Internal battery at 75%. System Idle.
Connected charger.
Power meter reads 2.24-2.28A (11.4W peak) from charger.
Batterybar reports 5400-6600 mw charge rate (1.3A peak)
Started Benchmark test to generate load (Passmark 8.0)
Power meter reading unchanged 2.28A max from charger.
Batterybar reports charge rate fluctuating down to 0 mw. (this is expected based on system power demand).
At end of test the Internal battery reads 76.3% charge.
Despite the load and Zero charge rate under peak load it did manage to charge some during the test.
Based on this, 6600 mw appears to be about the max charge rate while idle, not in standby, although nominal charge rate is more like 5600 mw eyeballing it. I think Batterybar can record readings with probably minor impact on results. From there we can calculate idle charge time and percentage rate etc. We will have to wall clock Standby Charge Time.
Tomorrow I should have a different charger, cables, and battery pack to test with.
ETA: Above 90% charge the charge rate begins to taper off drawing only 1.7A @ 95% so when your impatiently waiting for that last 10% to complete it does indeed take longer.
Additional info: at 100% charge, Batterybar continues to report 1,687 mw charge rate (337 ma) and the USB power meter shows a steady 1.0A from the charger while Idle so we are burning about 663 ma). Thus a 1.0A charger is not going to accomplish anything more than holding steady while Idle at best. Any charging from such a weak charger will only be done while in standby or shutdown. After quite a few minutes the charge rate did finally drop to 0 mw and the power meter still shows .7A+ from the charger.
Internal battery at 75%. System Idle.
Connected charger.
Power meter reads 2.24-2.28A (11.4W peak) from charger.
Batterybar reports 5400-6600 mw charge rate (1.3A peak)
Started Benchmark test to generate load (Passmark 8.0)
Power meter reading unchanged 2.28A max from charger.
Batterybar reports charge rate fluctuating down to 0 mw. (this is expected based on system power demand).
At end of test the Internal battery reads 76.3% charge.
Despite the load and Zero charge rate under peak load it did manage to charge some during the test.
Based on this, 6600 mw appears to be about the max charge rate while idle, not in standby, although nominal charge rate is more like 5600 mw eyeballing it. I think Batterybar can record readings with probably minor impact on results. From there we can calculate idle charge time and percentage rate etc. We will have to wall clock Standby Charge Time.
Tomorrow I should have a different charger, cables, and battery pack to test with.
ETA: Above 90% charge the charge rate begins to taper off drawing only 1.7A @ 95% so when your impatiently waiting for that last 10% to complete it does indeed take longer.
Additional info: at 100% charge, Batterybar continues to report 1,687 mw charge rate (337 ma) and the USB power meter shows a steady 1.0A from the charger while Idle so we are burning about 663 ma). Thus a 1.0A charger is not going to accomplish anything more than holding steady while Idle at best. Any charging from such a weak charger will only be done while in standby or shutdown. After quite a few minutes the charge rate did finally drop to 0 mw and the power meter still shows .7A+ from the charger.
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I observed 0.2A (200 ma) on the USB Power Meter coming from the charger while in standby.
If you were using a small 1.0A cell phone charger while in standby then you would get about 800ma for charging which comes to 4,000 mw. i.e. less than the rate the MS charger provides while Idle. It will charge but it wont be fast. Should be good enough for overnight charging unless you get in really late. Sometimes during normal usage it may not keep up and you'll lose ground. Note I have already seen a charger shut off (stop charging) for a while so they may not handle continuous load. Your Mileage May Vary. Id definitely recommend a stronger charger.
If you were using a small 1.0A cell phone charger while in standby then you would get about 800ma for charging which comes to 4,000 mw. i.e. less than the rate the MS charger provides while Idle. It will charge but it wont be fast. Should be good enough for overnight charging unless you get in really late.
Sometimes during normal usage it may not keep up and you'll lose ground. Note I have already seen a charger shut off (stop charging) for a while so they may not handle continuous load. Your Mileage May Vary. Id definitely recommend a stronger charger.Test using old HTC 1.0A Phone charger with MS cable, USB power meter inline, Batterybar monitoring internal battery.
Internal battery at 83.3%. System Idle.
Connected charger.
Power meter reads 1.25A from charger.
Batterybar reports 1800-2000 mw charge rate
After a couple minutes or so it dropped back to 0.54A draw from the charger
Batterybar reported Zero to -800 mw discharge while Idle.
After 20 minutes Idle time battery level is 82.7%
sill running at 0.54A from charger
Slowly discharging.
Pretty much as expected this will not charge the Surface while its on even while Idle although it does decrease the discharge rate with the half Amp the charger is supplying.
Next up a 2.0A Samsung Charger.
Internal battery at 83.3%. System Idle.
Connected charger.
Power meter reads 1.25A from charger.
Batterybar reports 1800-2000 mw charge rate
After a couple minutes or so it dropped back to 0.54A draw from the charger
Batterybar reported Zero to -800 mw discharge while Idle.
After 20 minutes Idle time battery level is 82.7%
sill running at 0.54A from charger
Slowly discharging.
Pretty much as expected this will not charge the Surface while its on even while Idle although it does decrease the discharge rate with the half Amp the charger is supplying.
Next up a 2.0A Samsung Charger.
Test using Samsung 2.0A charger with MS cable, USB power meter inline, Batterybar monitoring internal battery.
Internal battery at 81.0%. System Idle.
Connected charger.
Power meter reads 2.2A from charger.
Batterybar reports 5540-5775 mw charge rate
After 20 minutes charger still delivering 2.2A and charge rate around 5765 mw battery at 88.2%
Kicking it up a notch launched the Passmark 8.0 benchmark test @ 8:35
Power meter continues to read 2.2A
Charge Rate fluctuating then drops to Zero after a couple minutes under test. Battery at 88.5%
Now power drops from charger to 0.55A, charge rate negative and fluctuating as low as -7050 mw
@ 8:40 power meter 0.54A, charge rate -6965 mw, battery level 88.1%
@ 8:42 power meter 0.54A, charge rate -1490 mw, battery level 87.8%
Passmark test ended
8:45 power meter 0.55A, charge rate -612 mw, battery level 87.6% System Idle.
8:50 power meter 0.54A, charge rate 0 mw, battery level 87.5% System Idle.
9:00 power meter 0.54A, charge rate -505 mw, battery level 87.2% System Idle.
9:20 power meter 0.54A, charge rate -650 mw, battery level 85.3% System Idle.
Clearly as long as the charger is only supplying .5A we will continue to slowly discharge even at Idle.
Not sure how long we have to wait for the charger to ramp up IF it will. TBD.
I was impressed at first with the Samsung charger delivering .2A over its rated capacity for about 25 minutes but then it fell all the way back from 2.2A to .5A.
This is a disappointing result IMO. I think a typical user would feel like its not working and it would be hard to argue that it is.
I have to question the value and validity of the claim that you can use any charger without a disclaimer indicting unit must be in standby or off.
It has been an hour since the power level dropped to .5A from the charger and about 45 minutes since the system was under heavy load with no increase, still holding at .5A from the charger and slowly discharging. Now at 83.3%
Internal battery at 81.0%. System Idle.
Connected charger.
Power meter reads 2.2A from charger.
Batterybar reports 5540-5775 mw charge rate
After 20 minutes charger still delivering 2.2A and charge rate around 5765 mw battery at 88.2%
Kicking it up a notch launched the Passmark 8.0 benchmark test @ 8:35
Power meter continues to read 2.2A
Charge Rate fluctuating then drops to Zero after a couple minutes under test. Battery at 88.5%
Now power drops from charger to 0.55A, charge rate negative and fluctuating as low as -7050 mw
@ 8:40 power meter 0.54A, charge rate -6965 mw, battery level 88.1%
@ 8:42 power meter 0.54A, charge rate -1490 mw, battery level 87.8%
Passmark test ended
8:45 power meter 0.55A, charge rate -612 mw, battery level 87.6% System Idle.
8:50 power meter 0.54A, charge rate 0 mw, battery level 87.5% System Idle.
9:00 power meter 0.54A, charge rate -505 mw, battery level 87.2% System Idle.
9:20 power meter 0.54A, charge rate -650 mw, battery level 85.3% System Idle.
Clearly as long as the charger is only supplying .5A we will continue to slowly discharge even at Idle.
Not sure how long we have to wait for the charger to ramp up IF it will. TBD.
I was impressed at first with the Samsung charger delivering .2A over its rated capacity for about 25 minutes but then it fell all the way back from 2.2A to .5A.
This is a disappointing result IMO. I think a typical user would feel like its not working and it would be hard to argue that it is.
I have to question the value and validity of the claim that you can use any charger without a disclaimer indicting unit must be in standby or off.
It has been an hour since the power level dropped to .5A from the charger and about 45 minutes since the system was under heavy load with no increase, still holding at .5A from the charger and slowly discharging. Now at 83.3%
Spent the last 15 minutes on Standby and the whole time the power level from the charger remained at .5A. Battery level is 83.1% down slightly from last reading even after 15 min on standby.
Disconnected the cable for 30 seconds and reconnected and it immediately when to 2.2A. It seems you either have to wait a very long time or once the power is throttled back there is no throttle up.
Woe unto you if your charger or battery pack buckles or balks and throttles back or even worse shuts off completely. You will think you are charging and little or nothing will be happening or you might be discharging.
My grade for Casual micro USB charging. F
You will need to make sure the Charger or Battery Pack is UP to the task or you will be caught with your battery down.
Disconnected the cable for 30 seconds and reconnected and it immediately when to 2.2A. It seems you either have to wait a very long time or once the power is throttled back there is no throttle up.
Woe unto you if your charger or battery pack buckles or balks and throttles back or even worse shuts off completely. You will think you are charging and little or nothing will be happening or you might be discharging.
My grade for Casual micro USB charging. F
You will need to make sure the Charger or Battery Pack is UP to the task or you will be caught with your battery down.
