EOS RP not charging battery w/USB-C and PD

[JTTraverse]

I've recently acquired an EOS RP and have been trying to charge the battery using the USB-C port (mainly just to be sure I could do it in an emergency). I purchased a new braided Belkin USB-C to USB-C cable specifically for this, and today purchased an ONN dual-port wall charger that states "20W USB-C port fast charges with Power Delivery". Comparing it to other chargers with the same specs I presumed it should work. So I thought I was good to go with the power delivery requirement, etc.

Unfortunately, with the camera plugged in the green light on the back right that indicates it's charging never comes on. Does anyone have an idea what I might be missing. (Fwiw, the battery I'm testing with probably isn't completely dead at the moment if it needs to be for this to work.)
Thanks..

[JTTraverse · Accepted solution]

To resolve my own post/question: I've determined that you definitely need a specific kind of USB-C cable. I don't mean it must be a specific brand, but simply that even if the statements on the packaging suggest that it's a cable for 'power delivery'--there is a difference somewhere inside the various cables being sold out there.

I took the camera and the wall charger I'd purchased to a local store (Best Buy) so I could test cables on the spot. The clerk must have known what he was doing because he picked out one of their in-house 'Insignia' brands and it worked immediately! The only specific thing I see on the box is that while at first glance it looks like merely a USB-C to USB-C cable, it states 'Braided Charging Cable' in the top corner and in the small print on the back states 'USB-C cable transfers files and charges'.

So apparently there is something about charging that is built into some cables that is not in typical USB-C cables. (In my case the 4' cable I purchased is labeled on the bottom: 21K26T and NS-MCC421C)
What a relief...

[AtticusLake]

Congratulations on solving your issue -- checking the cable out in-store was definitely a good move.

You are right about the cable not being "merely a USB-C to USB-C cable".  As I said before, "Use a USB cable which is specifically rated for PD at the power you need".  A PD cable is different from a regular USB-C cable because it contains a chip which identifies it as being rated for PD at a specified power level.  A regular USB-C cable won't have the chip, and will not work for PD.  If the power level is less than your device needs, it also won't work.

Also, the printing on the package which says that it "charges" is completely bogus.  *ALL* USB cables will charge.  This has been true since the very first USB device was made.  The question is do they charge at 2.5 watts -- which won't run your camera -- or do they support PD at the wattage you need.

The problem is fraudulent cables which claim to be PD, but don't actually have the chip.  Ultimately the only way to avoid this is to insist on testing it in-store, as you did.

[Tuwimek]

This is about the length of the cable. Even if Canon use PD they only use low voltage so the length matters. Shorter better.

[JTTraverse]

As a side note to the USB-C cable topic (hoping this my be useful to know) I happened to purchase a power bank called a 'HenHot PD Pioneer 65W 20000mAh 2-port' mainly because it was fairly inexpensive (about $40) but had pretty good reviews. It definitely works with the camera as well as with the dummy battery--and they include a short 20" USB-C cable which will charge itself as well as the camera--and will work if you have a wall charger. (I could have saved the $20 for those other two cables if I'd waited...go figure 🙂

[normadel]

Just for my own education, I did a quick search for USB-C PD cables and found these sites explaining (?) it.......

https://www.familyhandyman.com/article/whats-the-difference-between-usb-c-and-usb-c-pd/

https://www.codrey.com/learn/usb-c-power-delivery-usb-c-pd-quick-explainer/

https://www.howtogeek.com/769888/what-is-usb-power-delivery-usb-pd/

I didn't see anything about a PD cable having resistors. The gist of the matter seems to be the cable has to be able to handle the currents called for in charging. I'm guessing the gauge of the conductors is the key. The OP referred to braided cables. This has nothing to do with electrical stuff. Braided cables are just stronger and prettier.

[AtticusLake]

The gauge of the conductors is the issue, as you point out; original USB cables weren't designed to handle anything like 5 amps.  But to be allowed to carry more than 3 amps, a USB cable has to include an E-Marker chip which identifies that it can do that.  So for high-power charging, an E-marker chip is mandatory, and older cheaper cables won't have one, because this is a new thing.

See here: https://www.inviolabs.com/blogs/news/what-is-e-marker-and-why-the-usb-c-to-c-cable-needs-it

[normadel]

Ahhhh....a CHIP. So now the whole story is told. Nowhere in my looking up PD cables did I see anything about what physically MAKES a proper PD cable different from an ordinary one.

Funny how even a USB cable is now an electronic device, not just wires and connectors!