Author Topic: USB cables--mixing them?  (Read 2524 times)

dodojojo

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USB cables--mixing them?
« on: December 05, 2015, 08:44:58 AM »
I bought a 600 lumen light for biking and as soon as I received it, I connected it to my USB charger--using my Kindle cable. I then sat down to read the instruction sheet for the light and came across a warning that I should use the cable that came with the light.  Not doing so risk harm to the light battery.  Of course I unplugged the light from the Kindle cable and connected it to the bike cable.

I know chargers differ--some charge faster than others.  I would think the charger would be the issue rather than the cable.  For all my USB charge devices, I just connect them to the USB cable in the room or nearest me.  It never occurs to me using cables not specifically made for the device would be harmful.

Is the warning for the bike light just a CYA by the manufacturer?  Or will using a different USB cable really harm the battery?

Davids

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Re: USB cables--mixing them?
« Reply #1 on: December 05, 2015, 10:57:32 AM »
I think it is a CYA. I have been mixing chargers, no issues for me.

stlbrah

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Re: USB cables--mixing them?
« Reply #2 on: December 05, 2015, 11:12:33 AM »
The cable itself shouldn't matter. The difference would be more of what is attached to the other end of the cable. I suspect some sort of power adapter plugged into the wall.

 I usually just check the voltage on the power adapters and make sure that they're the same.

Tyler

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Re: USB cables--mixing them?
« Reply #3 on: December 05, 2015, 11:34:46 AM »
You should be fine. 

Every USB device is standardized at 5V.  So if the connector fits, it's already running the right voltage.  Some USB chargers will support different currents (1A, 500mA, etc) but that simply affects the charging rate.  Some cables do include ferrite beads (the cylindrical lumps near the ends) to suppress high frequency interference, but I normally only see that with high speed data transfer and they should have no effect on a lamp.

Fun fact -- some companies include small resistors in the USB cables not to alter performance but to track whether it is an "approved" accessory.  When you use an "unapproved" accessory (that otherwise would work just fine) they either flash a warning screen or intentionally don't work.  They may claim it's about performance or safety, but it's usually about licensing fees and accessory sales.
« Last Edit: December 05, 2015, 12:13:12 PM by Tyler »

Syonyk

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Re: USB cables--mixing them?
« Reply #4 on: December 05, 2015, 01:33:15 PM »
It's fine... it might charge slower with the Kindle charger (since they don't draw much power, I assume they charge at 500mA instead of one of the higher rates), but it shouldn't hurt anything.  The charger only supplies what the device will draw, up to the charger's max output.

yuka

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Re: USB cables--mixing them?
« Reply #5 on: December 06, 2015, 12:21:48 PM »
If they still make Kindle cables like they used to, you may suffer from sub-optimal charging. Looking at some specs, 28 AWG only carries 1.4A for chassis wiring. 28AWG is normally when a cable starts feeling oddly thin and flexible. But it seems unlikely to me that the cable could endanger your light. microUSB is a particular spec, so a reputable company like Amazon should definitely be making cables to spec. There was some excitement recently about a Google engineer buying all the usb c cables on amazon, testing them, and writing a bunch of reviews about the ones that weren't made to spec, but those were third party international sorts of sellers.

BlueMR2

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Re: USB cables--mixing them?
« Reply #6 on: December 06, 2015, 03:17:07 PM »
I know chargers differ--some charge faster than others.  I would think the charger would be the issue rather than the cable.  For all my USB charge devices, I just connect them to the USB cable in the room or nearest me.  It never occurs to me using cables not specifically made for the device would be harmful.

Cables *can* be an issue.  I've never seen it cause damage, but with the quantity of garbage cables out there, if I was a manufacturer I'd definitely put in a CYA like that too!  :-)

patrickza

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Re: USB cables--mixing them?
« Reply #7 on: December 06, 2015, 11:55:08 PM »
As long as the cable can handle the current your charger supplies then there is no issue. If the cable gets warm then it's probably not up to the task. Most PC usb ports can only put out 500ma, so it's not really an issue with those. Wall chargers can be an issue.