[meathead88]

So me being a efficiency freak hooked my new Nokia DT-900 charging plate up to my Kill-a-Watt and did some quick tests.

Surprisingly NO, as in 0.0, Watts, Volts or Amps registered until I put my 920 down on the plate!

So good news, don't worry about leaving them plugged in all the time.

No how many more should buy? ;)

Seriously, Nokia is doing an excellent job here. They have really thought of everything for this round of phones, I'm impressed.
WP_20121122_005.jpg

[JammyGitz]

How much did your Kill A Watt cost? How much has it saved you?

[Braumin]

Wow that's pretty amazing because if you even just left the wall wart plugged in on most phones it would draw something. Nicely done Nokia!

[Brent920]

That's pretty damn impressive, I was going to do exactly them same test when my plate turns up.

How much power does it draw whilst charging?

Oh, and once fully charged, with the phone still on the plate, how much is it then?

If someone replicates you 0.0KWh then there's going to be a lot of incredibly impressed people.

[meathead88]

I'll try some more tests later. OMW to mom's for Thanksgiving :)

[meathead88]

$40. I think its saved a lot as its helped make decisions like in this case.
If my tests came back that these plates did suck juice, I would know i have to unplug them all the time, which would be a pain.

Biggest saving ever was using on PC to get my sleep settings perfect. That took a while, though...

[Xsever]

Thumbs up for the experiment. I was going to do this with mine but haven't had a chance since last night.

[Pedro Hicken]

Excellent.

Just out of curiosity, how long is the cable for the plate?

[socialcarpet]

Wait.

You're saying something positive?

I'm confused. Surely you didn't come to this forum to post something positive? Come on, tell us what's really going on.

Was the launch of the charging plate a disaster? Does it get too warm? Is the shade of black not to your liking? There must be something to complain about here otherwise the mods are going to have to lock this thread.

[Ekin Koc]

If you have time, could you check this;

- Phone gets 100% charge. Charging stops. So, you should read 0 again on the device. (I assume)
- Pick up the phone and lay it back down immediately. No matter how many times you do this in series, the charger lights up for a good 3-4 minutes. I'm curious if it pumps electricity at that point.

The reason is that I have the charger on my desk and I pick my phone up a lot, then put it back. I wanted to see if it is overcharging battery by pushing some juice each time I lay it down. You have the perfect equipment to see that :)

Thanks.

[andrewkeith5]

If you have time, could you check this;

- Phone gets 100% charge. Charging stops. So, you should read 0 again on the device. (I assume)
- Pick up the phone and lay it back down immediately. No matter how many times you do this in series, the charger lights up for a good 3-4 minutes. I'm curious if it pumps electricity at that point.

The reason is that I have the charger on my desk and I pick my phone up a lot, then put it back. I wanted to see if it is overcharging battery by pushing some juice each time I lay it down. You have the perfect equipment to see that :)

Thanks.

As long as the device is on there it won't read zero, as even once you get to a full charge it'll still push enough power to keep the device running without using battery power.

It probably takes a good 3-5 minutes for 1% for the last few percent of battery charge, as intelligent li-ion chargers will charge to ~70% rapidly and then progressively slower, as this helps to maintain the usable life of the battery (li-ion batteries are ridiculously sensitive). That's probably why you're seeing the charger jump on for such a seemingly long time when you drop the device back on after only a few minutes use

[meathead88]

Ok, my killawatt reads 0 watts when the 920 is off the charger, 7-8 when on the charger and charging and then 4-5 when fully charged.

[Ekin Koc]

Ok, my killawatt reads 0 watts when the 920 is off the charger, 7-8 when on the charger and charging and then 4-5 when fully charged.

4-5 even when the light is off on the charger?

[Brent920]

Charging cost (8W) = 0.1p per hour

Idle cost (5W) = 0.07p per hour

Phone not on charger = 0.00...

Basically way less than a penny a day for normal use.

[sircody]

Sorry to bare the true facts but here are the tested technical specs and all test from all groups have the same results. In order for a device that has a remote to be able to receive signals from the remote even in off/standby mode, it has a power draw. So for a wireless charger to be able to detect and perform the Handshake between the Transmitter and Receiver to start the charge, it has to have power. If this wasn't true, when you place the phone with a drained battery or in the off position, there wouldn't be a way to alert the charger. But the phone will charge on these chargers.. So one has to have power to run the Electronics..They have Standby Power, it's prob just that the Device you used to test doesn't have the ability to show it at that low, but low is still a power draw....

Wireless Power Efficiency - Wireless Power Consortium

WHAT ABOUT WIRELESS CHARGERS?

Our wireless chargers also contain an AC-DC power adapter. Let’s assume that is has the same efficiency (72%). Let’s also assumes that it has the same standby power (0.12 W). [footnote: Wireless chargers can have a much lower standby power, but this keeps the comparison easier.] The transfer efficiency of the wireless power link is typically 70%. And assume that the wireless charger replaces 2 wired chargers. The total energy consumption is:

• charging: 1 hours * 4 W / 72% / 70% = 7.9 Wh (we are now charging 2 devices simultaneously)
• standby (no load): 23 hours * 0.12 W = 2.8 Wh

[sircody]

Sorry, I forgot to say reason I found this post because some have read this and are doing Wireless Car Chargers and running power to a Constant source thinking it doesn't draw any, zero power and feel there is no threat of battery drain in the vehicle. I hope I didn't make it sound like there is no benefit or good reasons to go with the Wireless Charging because I would be the first to defend your side on how much energy savings in total is far more then the old way of charging. I have been involved in Induction for quit a long time now and have the Technology all around me, home, work, Jeeps and cars...LOL.....
Great Work by the way...

[LibbyJax]

I do not currently own a DT-900 but I am thinking about it and this seems to be good news for the power-conscious among us. Thank you for this.

SirCody,
One thing I've read about the DT-900 is that it has a low power magnet that holds the device in place when set on the stand. Could the 0 power reading be due to the fact that the magnet triggers a switch which then powers the device only when it is present on the stand? Just a thought.

-LibbyJax

Droid DNA
Nexus 7

[sircody]

I do not currently own a DT-900 but I am thinking about it and this seems to be good news for the power-conscious among us. Thank you for this.

SirCody,
One thing I've read about the DT-900 is that it has a low power magnet that holds the device in place when set on the stand. Could the 0 power reading be due to the fact that the magnet triggers a switch which then powers the device only when it is present on the stand? Just a thought.

Nah, the Magnets are to pretty much make it fool proof and they are setup to pull the phone in the right direction...Many are confused thinking that both receiver and transmitter have magnets...the phone part has metal disc and the pad as the magnet...

-LibbyJax

Droid DNA
Nexus 7

[sircody]

Nah, the Magnets are to pretty much make it fool proof and they are setup to pull the phone in the right direction...Many are confused thinking that both receiver and transmitter have magnets...the phone part has metal disc and the pad as the magnet...

[david90531]

That's awesome, thanks for the post

[meathead88]

Great sale on these here: 2 for $52!!!!

Nokia DT-900 Wireless Charging Plate for Lumia 820/920: 2 for $52 or 1 for $29 + Free Shipping - Slickdeals.net?

[Gurggles]

Now I can't wait to test this on my Kill-a-watt! I have the DT-910 that I can test against the DT-900.