Advice sought on why 6.8A USB charger melted USB cable today

[Danny D.]

I was told to ask this question here...

I would just like some advice since I melted a USB cable today
and I realized I don't have the proper troubleshooting skills.

I bought over a half-dozen "Hype Volt" 6.8Amp USB chargers for
stuffing the Christmas stockings:
https://i.imgur.com/Zavgm4B.jpg

I kept one for myself, but, when I used it last night on an iPad
and on an Android phone, the iPad lightning cable melted!

When I pulled it off the iPad, it was noticeably extremely hot,
but it doesn't seem to have damaged the iPad (AFAIK).

So, I'm just wondering what happened, and, more importantly, when
I look at the specs for this device, they don't make sense to me,
so, I have difficulty troubleshooting what the problem is/was.

Here are all the specs off the package and off the device:
DGL Group Ltd. Hype Volt HV-6PT
Model: HC363-5U (also listed as HV-6PT-WHT)
Input: AC 110VAC/60Hz - 220VAC/50Hz (800mA max)
Output: DC 5V, 6.8A total
Maximum Power: 40W
Supercharge: 5V@2.4A maximum
Universal: 5V@1A maximum

Description:
http://www.amazon.com/Hype-Compact-Automatically-Adjustable-Adapter/dp/B00T3FQBHO
http://www.walmart.ca/en/ip/hype-volt-68a-wall-adapter-with-5-usb-ports/6000193376994

My questions are varied, because I don't understand how it works,
nor how it could have overheated the cable to the tablet.

Here's what it says on the package:
"Smart USB Technology: This adapter automatically adjusts power
output to fit your charging device. Tablets and e-readers require
2 Amp charging, and this adapter will reroute power to the
appropriate USB port you use."

"Charging Combinations:
- 2 tablets + 3 mobile devices
- 1 tablet + 4 mobile devices
- 5 mobile devices
- 3 tablets"

I am confused about both the pure math and how this operates.

Q1: Since 6.8A times 5VDC is only 34Watts (not 40 Watts), how
can they very clearly label it as a 40Watt device?

Q2: How does the device "know" to give tablets 2.4 Amps
(12 Watts) but a "mobile device" only 1Amp (5 Watts).

Q3: What if a mobile device "wants" more than 1 amp?
Does the charger give more than 1A to the device?

 

[Danny D.]

> I was told to ask this question here...

A fundamental question is why the package says the output is 40Watts
when the maximum output current is 6.8Amps at 5VDC?

Here is a description online which says the same thing:
https://www.touchofmodern.com/sales/hype-volt/smart-adapter

The manufacturer is listed as "DLG Group LTD" on the package:
https://i.imgur.com/30qxupn.jpg

And, as "Hype Volt" on the device:
https://i.imgur.com/8bl7ypU.jpg

The DGL Group seems to be located here:
http://listings.findthecompany.com/l/8916005/DGL-Group-Ltd-in-Edison-NJ
195 Raritan Center Pkwy
Edison, New Jersey 08837-3650
(718) 499-1000
http://www.dglusa.com

So, I called them, and spoke to a salesman, who didn't know why the
discrepancy.

 

[Tim Wescott]

On Mon, 30 Nov 2015 19:04:44 +0000, Danny D. wrote:

I was told to ask this question here...

I would just like some advice since I melted a USB cable today and I
realized I don't have the proper troubleshooting skills.

I bought over a half-dozen "Hype Volt" 6.8Amp USB chargers for stuffing
the Christmas stockings:
https://i.imgur.com/Zavgm4B.jpg

I kept one for myself, but, when I used it last night on an iPad and on
an Android phone, the iPad lightning cable melted!

When I pulled it off the iPad, it was noticeably extremely hot,
but it doesn't seem to have damaged the iPad (AFAIK).

So, I'm just wondering what happened, and, more importantly, when I look
at the specs for this device, they don't make sense to me,
so, I have difficulty troubleshooting what the problem is/was.

Here are all the specs off the package and off the device:
DGL Group Ltd. Hype Volt HV-6PT Model: HC363-5U (also listed as
HV-6PT-WHT)
Input: AC 110VAC/60Hz - 220VAC/50Hz (800mA max)
Output: DC 5V, 6.8A total Maximum Power: 40W Supercharge: 5V@2.4A
maximum Universal: 5V@1A maximum

Description:
http://www.amazon.com/Hype-Compact-Automatically-Adjustable-Adapter/dp/
B00T3FQBHO
http://www.walmart.ca/en/ip/hype-volt-68a-wall-adapter-with-5-usb-
ports/6000193376994

My questions are varied, because I don't understand how it works,
nor how it could have overheated the cable to the tablet.

Here's what it says on the package:
"Smart USB Technology: This adapter automatically adjusts power
output to fit your charging device. Tablets and e-readers require 2
Amp charging, and this adapter will reroute power to the appropriate
USB port you use."

"Charging Combinations:
- 2 tablets + 3 mobile devices - 1 tablet + 4 mobile devices - 5
mobile devices - 3 tablets"

I am confused about both the pure math and how this operates.

Q1: Since 6.8A times 5VDC is only 34Watts (not 40 Watts), how
can they very clearly label it as a 40Watt device?

By printing "40W" on the package and figuring that no one is going to
call them on it.

BTW: 800mA at 110V is 88W -- that's less than 50% efficiency unless the
thing doesn't look like a resistive load.

Q2: How does the device "know" to give tablets 2.4 Amps
(12 Watts) but a "mobile device" only 1Amp (5 Watts).

It doesn't. It knows to hold its output voltage steady at 5V, regardless
of current (at least, hopefully, until the current gets to be too much
for it).

Q3: What if a mobile device "wants" more than 1 amp?
Does the charger give more than 1A to the device?

Yup.

I'm not sure why your USB cable overheated, unless it was one made
thinking that the end device would consume no more than 500mA, and the
iPhone knew that it could pull way more than that. It still shouldn't
have burnt up, but you seem to be in the habit of buying stuff on price...

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

 

[Danny D.]

Tim Wescott wrote, on Mon, 30 Nov 2015 19:48:43 -0600:

By printing "40W" on the package and figuring that no one is going to
call them on it.

BTW: 800mA at 110V is 88W -- that's less than 50% efficiency unless the
thing doesn't look like a resistive load.

Thanks for correcting the input VA.

As for the 40Watt figure, I think it's a lie because I googled
for the part number that is printed on the side of the unit:
https://i.imgur.com/8bl7ypU.jpg

Notice that HC363-5U printed on the unit?

Googling for just that, I find the same unit only with a different
set of markings, which is listed as being 35Watts, which is closer
to the 34 Watts that 6.8 Amps gets us at 5 VDC:
http://www.amazon.com/Hausbell-35W-HC363-5U-Certified-Family-Sized/dp/B00NUREFMO
"Hausbell 35W HC363-5U UL Certified (UL No:E310745)
Family-Sized USB Wall Charger Plug Smart Charger,
Single USB Output 2.4A Max,Output total 6.8A Max,5P-USB Output
for Apple and Android Smartphones,Tablets and More(White)
by Hausbell, Price: $59.99 & FREE Shipping"

Here's the same unit, this time for $15 but it also calls it 35 Watts:
http://www.amazon.com/Hausbell-Charger-Certified-Foldable-Smartphones/dp/B00ORLR1X2

Here's another, again listing it as 35Watts:
http://www.sportinggoodsoutdoor.com/p/detail/B00ORLR1X2/Pre-sale-promotionHausBell-35W-HC363-5U-UL-Certified-UL-NoE310745-Family-Sized-USB-Wall-Charger-Plug-Smart-ChargerSingle-USB-Output-24A-MaxOutput-total-68A-Max5P-USB-Output-for-Apple-and.html

And another listing it as 35 Watts:
http://hausbell.net/products/cell-phones-accessories/travel-chargers/family-sized-usb-wall-charger-5p-usb-output-238.html

And another listing it as 35Watts:
http://macbookpro.deal2hand.com/review-Hausbell-35W-5-Port-USB-Wall-Charger-UL-Certified-with-Foldable-Plug-for-Apple-and-Android-Smartphones-Table_B00ORLR1X2.html

So, pretty much, the 40Watts is either a bold-faced lie, or it's
not the wattage of the output (which is closer to 34 Watts).