Review request for HKJ [USB Power Devices]

fsp-group.com.tw/index.php?do=pressinfo&id=255
newertech.com/products/nupower-usb-c-power-adapter/
trust.com/en/product/21478-moda-universal-60w-usb-c-charger
trust.com/en/21478/leaflet/en-GB
google.com/search?q=8713439214789&tbm=shop
satechi.net/index.php/satechi-type-c-power-meter

If you’re handy with the computer get a “Twinkie” (Type-C Power Delivery Sniffer)
https://www.amazon.com/dp/B015X29HLM

Or this one just for volt / amp measurements:
https://www.amazon.com/dp/B01NAWYSVK

Be careful with untested USB C chargers, even though it is the future of USB connectivity, it is still very unsafe. It might take a couple years for it to fully standardize.

You could take a look at YZXStudios stuff, like the ZY1271 which has two usb-c ports and ZY1273 which has one. I shot an e-mail to Franky Tong for some info on obtaining one or both.

wow the YZ1271 is a thing of beauty. I dread the price but heh the good things in life are often bloody expensive :smiley:

The ZY1273 is $42,99 shipped from Franky, I already know that, so I expect the ZY1271 to be about the same or maybe a few dollars more. As soon as I get a reply, I'll post more info.

Hi @HKJ Could you explain the importance of Y-capacitors in chargers and its relation to touchscreens?

Thanks

I did explain a bit here: How does a usb charger work

It reduces the electric noise generated and touch screens are sensitive to some electric noise.

The reason for the Y/safety capacitor is not so much for the touch screens, but due to legal reasons (The power supply would not pass CE & FCC test without it).

Thanks a lot for this. very informative.

Hello!

Lil question aimed at HKJ. I've observed certain USB power devices offer a relatively low output voltage. You once told me you measured output voltage from a small patch of cable, which without a doubt has less resistance than the actual 1-2m cables people employs (cable plus connector losses). I think this can mean those sources won't be able to actually fully deliver their rated current, as by the time it reachs the device voltage is too low and it would re-negotiate (lower) the charging rate. As a general rule, I'd start to be concerned with anything below 5.1V for USB power devices without load output voltage compensation.

Comments?

Cheers ^:)

most of my supplies seem to provide ~4.95-5.05v direct from the supply rather than at the end of a test lead.

We need psu`s with an cable that monitor the voltage at the connector end and boost the adaptor voltage to compensate for voltage drop along the leanth, how could this be done.

I suppose power adapter`s with a captive cable can be compensated for to a certain extent by the manufacturer, but usb power adapter`s where the manufacture does not know the leanth or quality of the cable that is going to be used is a bigger problem.

My Belkin 2.4amp usb adapter boosts the voltage when it is under load, unloaded it measures at 5.10v and under 2.6amp it only dropped to 5.09v but this is only at the usb connector on the power adapter, I was measuring 4.5v at the end of an 6ft cable.

John.

I use a short thick cable because I want to measure the usb supply, not the cable. This is not perfect, my cable has some losses, they can be seen on multiple output chargers. Single output is measure with my standard cable, when paralleling multiple outputs, I have many short cables in parallel and my measured voltage will be slightly higher at the same current.

When used to charge devices the charge current may depend on the cable, it depends on the device. Some devices are more sensitive to low voltage than other. When testing usb chargers I usual simulate a long cable with a 0.5ohm resistor in series with the 5 volt, this can give a good idea how sensitive the device is.

Chargers without an optocoupler will often increase the voltage slightly when loaded, but my preferred chargers has 5.2V always.

We previously discussed about this, I believe your methodology is pretty allright here. I just wanted to pinpoint it would be a nice idea to add a comment in this regard whenever convenient in your final words in the reviews. I personally would not buy something like the Energizer High Tech Mains charger 336:

At 1A load, its already is at ≈4.9V, so there's very very little voltage left to be dropped by cable and connector resistances. Besides, even the “premium” commercial cables suck, in general terms, with regards to their lenght/gauge relationship, which means the voltage drop will have a noticeable impact at high current levels. And if you factor in some people treat their connectors like crap, it's easy to understand why they can't stop complaining about slow charging speed.

Needless to say, I build my own cables.

Cheers ^:)

Hi Henrik

Have you tested the Amazon basic 2.4amp usb charger, they seem to be a reasonable price, You should be able to get an EURO plug version from your local Amazon.

https://www.amazon.co.uk/dp/B01FI2P0WW/ref=twister_B01N1UZ3JO?_encoding=UTF8&psc=1

Thanks

John.

Amazon do not have a Danish department, I either use German or English Amazon, with mains equipment usual Germen because I then get the correct plug.
Anyway I have ordered one, but it will be some time before I get around to test it, I have a fairly long queue of usb chargers.

Hi Henrik, what do you think of this, only $3.65 delivered. (sorry about the bold it will not turn off)

1.2v 12v 18650 Li-ion Lithium Battery Capacity Tester + Resistance Lead-acid Battery Capacity Meter Discharge Tester

https://www.aliexpress.com/item/-/32681742031.html?uttaskid=37002&utcontentid=976&utalgorithmid=2&tracelog=rowan&rowan_id1=eclc_en_7_1_en_US_2017-04-06&rowan_msg_id=johnUTT_37002_$a4ea5d470c6b441eb3dde94ac2d435e1&ck=in_edm_other

John.

The previous link looks much better if “junk free”: https://www.aliexpress.com/item/-/32681742031.html

The bold attribute goes off by selecting all off the involved stuff (or more) and applying/switching it a couple of times, at most (shortcut: CTRL + B).

Cheers

I prefer the ones with constant current discharge. For this one you need to get a couple of power resistors and will not have a constant current discharge.

Something like this is much better: Test/review of Electronic load 60W
The heatsink with a fan do not get as hot as a power resistor and can work at many different currents.

Not a USB power device, but this looks interesting

https://www.aliexpress.com/item/PR10-C-EU16A-home-power-metering-socket-home-energy-meter-power-recorder-electricity-meters-16-currency/32695358611.html

I’ve been using Technoline power meters until now and they have been independently verified as accurate, but this has more features.

I have been using this for a month now and according to my cheap Fluke it seems to be accurate. I like the ZKE software too which is the same as with the USB meters.

http://www.ebay.com/itm/252205821159