Inexpensively Learn about your GPS battery charging

 

A lot of questions arise here regarding folks worried about their device's battery, various charging methods, etc., etc.

You can learn a lot about your various devices charged via USB by buying a simple device. I'm sure these can be widely found but I bought the two I have on eBay. I can't guarantee that this is the best price or the vendor I used, but it is a good price from a US vendor with great feedback. If patient regarding delivery times, you can find them even cheaper from Chinese vendors. Check it out:

https://www.ebay.com/itm/KEWEISI-4V-20V-0-3A-USB-Charger-Pow...

What can you learn by adding one of these between your USB output socket and device being charged? Let me count some ways:

-You will see the instantaneous voltage and current being sent to your GPS and this is a great way to distinguish between low power 0.5A chargers and the 1-2A chargers which can charge your GPS much more quickly.

-As your GPS device's battery approaches a full charge, you will see the current being drawn by the device drop from its max to a smaller value, eventually dropping to 0.000A letting you know the GPS is fully charged and the device's battery protection circuitry is preventing overcharging.

-If charging a fully depleted GPS battery, you can see how many mAh was sent to the GPS and by comparing that value to the capacity of the original battery, you may learn about how well an aging battery is doing compared to a new one. You also see the time it took for a full charge to occur given the charger's power and state of the battery when starting the charge.

-Even more fun is using one of these for your cell phone as it charges, especially when some cell phones and cell phone chargers use a form of Fast Charging. This device will show how the Fast Charging works, whether it's a higher amperage charger, or for devices like many Samsungs, that the charger sees a device capable of Fast Charging and capable of accepting charging voltages of 9 or even 12V. Given the number of counterfeit Samsung Adaptive Fast Chargers being offered on eBay by Asian Sellers at suspiciously low prices, you may well find that the counterfeits do not offer 9V or 12V charging when the charger senses a 9 or 12V capable device to be charged and they simply offer higher current charging at 5V. For this reason, avoid buying a USB power measuring device that can not show much more than 5V. Several cheaper devices won't show USB voltages above about 7.5V making them useless when monitoring a Fast Samsung charger trying to recharge a Fast Charge capable Samsung device.

A couple YouTubes:

https://www.youtube.com/watch?v=a41MNIKJYWw (Go to about 2min 30 seconds to avoid the sponsorship video)

https://www.youtube.com/watch?v=5LYwFt0ic24

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Great find ...

and excellent write up CraigW! Thanks.

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Alan - Android Auto, Nuvi 3597LMTHD, Oregon 550T, Nuvi 855, Nuvi 755T, Lowrance Endura Sierra

Thanks Craig. An interesting

Thanks Craig. An interesting find!

--
Maps -> Wife -> Garmin 12XL -> StreetPilot 2610 -> Nuvi 660 (blown speaker) -> Nuvi 3790LMT

Thanks

Good information.

Good Advice

After reading your post I ordered one of these off eBay for $4...sekker located in US...fingers crossed.

I can think of at least a dozen devices to try this on. Thanks !!

Thanks

Thanks for posting CraigW. I too ordered one. US $ 2.43 Cdn $ 3.70 free shipping from China. If it takes more than three months, I don't care since I won't be home until the end of April.

--
Nuvi 350 long gone, Nuvi 855LMT, Nuvi 2797LMT, 3790LMT passed on to my daughter. Using Windows 10

Good Job Craig

Thanks for the two links and information you posted.
This can be very useful for some of our members that are interested in their battery's state of charge.

Regards
Will

--
Nuvi 660 2460LMT Sold My 765T

Ditto

Melaqueman wrote:

Thanks for posting CraigW. I too ordered one. US $ 2.43 Cdn $ 3.70 free shipping from China. If it takes more than three months, I don't care since I won't be home until the end of April.

I'm pretty sure the two times I ordered one of these Keweisi devices, I also ordered from China from a high-feedback seller. For the link in this thread, I made sure to find a US Seller with great feedback but at a higher price since I didn't want to be responsible for a bad delivery experience for the users here. Yup, if you're willing to wait 3-7 weeks with maybe a 5% chance of it being lost in the mail/Customs and refunded, you could buy a good 2-3 of these testers from Asia for the price of one from the USA. Of course, for someone living in Canada/Mexico and only traversing the USA a couple times a year, why buy from a US Seller? wink For those not wanting to go the eBay route, I'm pretty sure Banggood sells them as well.

info device

To make it clear, before this question will surface. Device that CraigW wrote about is good for "educational" and information purpose. If you are curious how much energy your device is using at particular moment, it will give you an answer.

But it will not "repair" old or dead battery! It may help detect some problem with device showing unusual power usage, but still will not show what is wrong.

For me it would be interesting if this device could register parameters change with time, either through connection with computer or internal memory. This way you will be able to see whole cycle of charging without watching it for hours in real time smile But in future it's possible that it have this functionality.

USB Meter

They make meters that will plot the performance over time - but they cost more. Here's an example (I have not tried this model)

https://www.amazon.com/AVHzY-Multimeter-Current-Detector-Cap...

--
GO

Great Info

Thanks for sharing ..... very interesting !

Travel Safe!

Thanks, but shop

I'm grateful to CraigW for alerting me to the existence of this product category. I've ordered one from the seller linked in the first post.

There are plenty of products in this category on offer (I suspect many are made in one town in China using the same chip). The linked seller was selling this product for $3.49 in December 2017, and is charging $8.79 plus cheap shipping as I type. So you may wish to shop a little. Not only for price.

One thing to watch for is voltage and current range. While the original USB is stated to be 5V, plenty of real implementations (especially of chargers which just use the connector format but are not full-up USB devices) put appreciably more on when not loaded. Further USB-C allows a negotiated voltage up to a nominal 20V. I'd advise checking for a claim up to nearly 10V (which the linked one has) at least.

Similarly for current, while elder days USB devices were not supposed to get very much, there are plenty of higher-output chargers out there, and devices able and eager to take more if they think it available. I'd look for 2A limit at the very least, and value up past 3.

It appears that the readability of the displays varies appreciably among the various products out there--I'd suggest reading review comments and deciding whether you think your choice is suitable to your purpose.

I'm not clear on whether all the products totalize the same way. Ideally I'd like one that separately displayed mAhr and Whr, resettable by a push button. While real-time display of current conditions is already valuable, in making a choice I'd compare the totalized display(s) to one's needs.

I'm getting old. The idea that you can buy something that does this for five bucks is just mind-boggling to me. I'll post again when mine shows up and I get some usage out of it.

I've got various questions in mind already. Just for one example: does my tablet really get higher power delivered to it when it detects that it is being supplied by its own charger and announces high rate on the display than when I plug it in to a socket capable of supplying over 2A but not delivering the secret handshake?

--
personal GPS user since 1992

If I understand you question...

archae86 wrote:

I've got various questions in mind already. Just for one example: does my tablet really get higher power delivered to it when it detects that it is being supplied by its own charger and announces high rate on the display than when I plug it in to a socket capable of supplying over 2A but not delivering the secret handshake?

If I'm understanding your question, I can say that my genuine Samsung Adaptive Fast charger (and my Samsung "Adaptive Fast Capable" power bank which can offer 9V to a Samsung Adaptive Fast charging smartphone and even 12V to a tablet) will pass the info between charging side and receiving side to allow the charger to offer 9V rather than the standard 5V to dumb receiving devices so I think it likely that your putting the meter device between charger and chargee will allow the high power handshake needed for high power charging, whether higher amps or higher voltage and amps. When adding the meter in the middle when charging my cell phone, it shows charging at about 9V and current from about 1.5A when starting and dropping to 0A when fully charged.

Of course, we all want to hear everyone's results and tests thought up and performed.

From experience...

Knowing that there is no memory charge in new devices, more small charging increments is m