Charging a New Dell USB C Laptop Via Old Dell Charger

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arf1410
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Charging a New Dell USB C Laptop Via Old Dell Charger

Post by arf1410 »

just got a new Dell laptop, that has USB-C charging only, not the normal Dell Barrel plug used for the last 20 years. I've got a handful of those old chargers around, and was thinking I could pick up some cheap barrel to USB C adapters for under $10 bucks. Seems like the few I could find (including at Dell.com) are sold out, and were a bit expensive for what they seem to be. I can find some cheap ones on eBay.. but those concern me a bit.

Is the issue more complex than a simple adapter? Both the old, and new chargers, seem to output the same voltage, and amps.
livesoft
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Re: Charging a New Dell USB C Laptop Via Old Dell Charger

Post by livesoft »

I think the issue is more complex than a simple adapter. USB-C devices "hand-shake" with the charger to provide what I might call optimal possible charging. That is, the chargers do NOT output the same voltage and amps which depends on the handshaking. One can use a USB multimeter to see this in action. The chargers may be rated for the same max output voltage and current, but that does not necessarily mean that's what gets sent to the device being charged. Also as batteries are charged, the current is automatically reduced.
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dukeblue219
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Re: Charging a New Dell USB C Laptop Via Old Dell Charger

Post by dukeblue219 »

I would be surprised if it's trivial to adapt a barrel adapter to USB C. USB-PD (the power delivery standard using the physical USB C connector) has several negotiation steps to settle on the desired voltage and current for charging. The barrel chargers don't work quite the same way (and there are many barrel charger form factors from Dell over the last 20 years. Not just one)

I'm an electrical engineer, but not intimately familiar with USB-PD

Get a good USB C fast charger and enjoy using it with any and all other USB C devices you have or may acquire. It's a good standard .
02nz
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Re: Charging a New Dell USB C Laptop Via Old Dell Charger

Post by 02nz »

I'm skeptical that will work, and more to the point, why would you even bother? You can get a high-quality USB-C charger from Anker for under $40, and there will definitely be deals this week. Lots of options - folding prongs, extra USB ports, even a built-in battery. They're so much lighter, more compact, and more versatile than an old proprietary laptop charging brick. I just got this one, which has swappable travel plugs.
dukeblue219
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Re: Charging a New Dell USB C Laptop Via Old Dell Charger

Post by dukeblue219 »

Before you buy one you might as well post the model here. We might be able to recommend something specific. Higher powered Dell laptops that ship with 90 or 130w USB C charger don't always play nice with lower power 45w or 65w chargers.

It's standardized, yes, but the rating still matters.

In my case I bought a 90w Anker charger and an appropriate cord. I carry it in my backpack full time, so I never need to bring another charger with me. Work or personal laptop, phone or tablet, I'm covered. The original chargers are at work and home, respectively.
livesoft
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Re: Charging a New Dell USB C Laptop Via Old Dell Charger

Post by livesoft »

I would like to point out that a USB-C wall charger will be able to charge older low-power USB-A devices if one uses a proper adapter since the USB-C charger should try to handshake and see that the device being charged is not a USB-C device. However, if the adapter is cheap it is possible that it will let the USB-C charger "brick" the low-power device being charged, so do not come crying to me if your ruin your low power device. :twisted:
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iamlucky13
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Re: Charging a New Dell USB C Laptop Via Old Dell Charger

Post by iamlucky13 »

dukeblue219 wrote: Mon Nov 21, 2022 7:19 pm Before you buy one you might as well post the model here. We might be able to recommend something specific. Higher powered Dell laptops that ship with 90 or 130w USB C charger don't always play nice with lower power 45w or 65w chargers.
Weirdly enough, in lieu of docking adapters, my employer has started issuing the new Dell "hub" monitors, which only put out 65W over USB-C. Our standard engineering laptop ships with a 130W charger.

So the coworkers around me who recently received these monitors are getting very used to seeing the warning that their charger is underpowered.

I missed the monitor upgrade opportunity, but I tried the charger for my personal laptop, which is also 65W if I remember right, and I get the same warning, but no issues. It just takes a long time to charge. I haven't tried any long, intense drafting sessions from home to see how much trouble it has keeping up under load.
02nz wrote: Mon Nov 21, 2022 7:06 pm I'm skeptical that will work, and more to the point, why would you even bother?
The Dell barrel to USB-C adapter is large enough I presume it has the necessary electronics inside to negotiate a UBS power delivery handshake at an acceptable voltage.

But it is unclear how much value it really has, since the barrel-to-USB-C adapter is $40, while a new 65W USB-C power supply is $45 for a cleaner overall setup. I like the physical form of the lastest generation of Dell power supplies. They're nice and slim for easy packing in a bag. For such similar prices, I would just get an additional power supply.
gavinsiu
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Re: Charging a New Dell USB C Laptop Via Old Dell Charger

Post by gavinsiu »

It would work. YOur old Dell adapter are basically dump adapter that supply a certain voltage. A usb adapter will negotiate to see if it's compatible. To simplify it, your laptop might ask the adapter, can you give me a 100W and the adapter might say no, and then the computer might can you support 65W and the adapter might say yes and then charging begins. For legacy equipment that does not do negotiation, the adapter may use the lowest power to avoid damaging the legacy equipment.

You are better off getting a generic power adapter. A lot of laptop usb C adapters are interchangable. If you have a laptop with usb, try that or get a cheap chromebook usb C adapter.

However, this might not work if your computer is one of the higher power units. Some of the gaming laptop might require power in exccess of over 100w, those might require more special adapters.
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mrmass
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Re: Charging a New Dell USB C Laptop Via Old Dell Charger

Post by mrmass »

I use and have provided users with the Dell branded barrel to USB-C adapter and they work great. I got most from Dell a few from EBay.

I couldn’t stand tossing out the nice 90 watt bricks.
Marylander1
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Re: Charging a New Dell USB C Laptop Via Old Dell Charger

Post by Marylander1 »

arf1410 wrote: Mon Nov 21, 2022 6:27 pm just got a new Dell laptop, that has USB-C charging only, not the normal Dell Barrel plug used for the last 20 years.
I had 2 Dell laptops with barrel plugs, and they looked similar but weren't interchangeable, which was a royal pain. And who doesn't have a box of old proprietary adapters, unsure what specific device(s) each one fits?

USB-C is now the "normal" way to power a laptop, or a phone, or a flashlight, or many other devices. As long as the power supply provides enough wattage, they just work. It's an awesome new world.
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arf1410
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Re: Charging a New Dell USB C Laptop Via Old Dell Charger

Post by arf1410 »

mrmass wrote: Tue Nov 22, 2022 5:05 am I use and have provided users with the Dell branded barrel to USB-C adapter and they work great. I got most from Dell a few from EBay.

I couldn’t stand tossing out the nice 90 watt bricks.
the included adapter with my Dell is 65w...

and my hope was to find a $8.99 adapater, rather than Dell's $29.99 version (out of stock) or an entire new power brick. Can you provide a specific link to a product that you use and are happy with?

EDIT - just seeing amazon has the entire USB-C charging bricks for under $10. I had no idea they were that cheap. Any risk of using a cheap, after market charger? Is the laptop smart enough that if it doesnt like the quality or quantity of power being supplied, it would simply refuse to charge, as opposed to damaging something?
chinchin
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Re: Charging a New Dell USB C Laptop Via Old Dell Charger

Post by chinchin »

Worst case, you start a battery fire from overcurrent.

https://www.miamiherald.com/news/nation ... 19065.html

https://www.tingfire.com/device-safety/ ... use-fires/

Don't have the link, but I read an article comparing an Apple cell phone charger brick with a generic one, and there were measurable differences in power / build quality.
not financial advice
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mrmass
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Re: Charging a New Dell USB C Laptop Via Old Dell Charger

Post by mrmass »

arf1410 wrote: Tue Nov 22, 2022 11:47 am
mrmass wrote: Tue Nov 22, 2022 5:05 am I use and have provided users with the Dell branded barrel to USB-C adapter and they work great. I got most from Dell a few from EBay.

I couldn’t stand tossing out the nice 90 watt bricks.
the included adapter with my Dell is 65w...

and my hope was to find a $8.99 adapater, rather than Dell's $29.99 version (out of stock) or an entire new power brick. Can you provide a specific link to a product that you use and are happy with?

EDIT - just seeing amazon has the entire USB-C charging bricks for under $10. I had no idea they were that cheap. Any risk of using a cheap, after market charger? Is the laptop smart enough that if it doesnt like the quality or quantity of power being supplied, it would simply refuse to charge, as opposed to damaging something?
Heres what I am using now Dell LDD75B-USBC160

If you open google search up, just type Dell LDD you'll see the different versions auto populate. Ebay doesn't have any of the 7.5s, but seems to have lots of the 4.5s.

https://www.dell.com/en-us/shop/dell-ad ... ccessories

the 75 part is the barrel size 7.5mm

They also sell the 4.5mm version
https://www.dell.com/en-us/shop/dell-ad ... ccessories
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mrmass
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Re: Charging a New Dell USB C Laptop Via Old Dell Charger

Post by mrmass »

BTW all the chargers I'm reusing were from Latitude 7440s, 7490s 7450s, and 7470s. I guess they all use the 7.5mm barrel.
02nz
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Re: Charging a New Dell USB C Laptop Via Old Dell Charger

Post by 02nz »

arf1410 wrote: Tue Nov 22, 2022 11:47 am EDIT - just seeing amazon has the entire USB-C charging bricks for under $10. I had no idea they were that cheap. Any risk of using a cheap, after market charger? Is the laptop smart enough that if it doesnt like the quality or quantity of power being supplied, it would simply refuse to charge, as opposed to damaging something?
I've had good experiences with Anker and ZMI. RavPower, too, but they got kicked off of Amazon.

This 65W Anker is what I just got, $24. You can get smaller ones, but they're generally more expensive.
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mrmass
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Re: Charging a New Dell USB C Laptop Via Old Dell Charger

Post by mrmass »

Or just get one of these https://www.ebay.com/itm/134055817260?h ... Swou9h-u19

OEM 65 USBC.
classpro
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Re: Charging a New Dell USB C Laptop Via Old Dell Charger

Post by classpro »

Some people are posting that USB chargers are readily available cheaply (under $10), but it's important to realize that not all USB-c chargers work with all USB-c devices. There are 5v USB-c chargers that will not power a laptop at all. There are 18w USB-C charges that will not put out more than 12v at 1.5 amps (while laptops might need 20v at 2 amps (40 watts) on the low end or up to 5 amps(100w)) or more on the high end). You have to see whether the charger is capable of putting out the voltage and amperage your device needs. Well, if you get a 100w USB-c charger, you should be good to go with just about any USB-C device now (but they are coming out with even higher voltages and amperages), and those 100w adapters are not $10! You also need USB-c cables that are capable of handling the amperage. So be careful and understand what you are doing. It's a great standard, but it's not nearly as simple as it appears. Just because the connector fits doesn't mean it's going to work properly with your device.

I don't know whether simply converting the tip on a dell adapter to USB-c will work or not in a newer Dell laptop. Kind of a scary thing to try, although it may not harm anything if it doesn't work. Dell adapters have always been a pain in the A** because they have a slightly odd tip size and they have sensing circuitry to make it difficult to work with a third party adapter. I hate this proprietary stuff. That's one good thing about USB-c - at least there are standards.

Other than the Dell to USB-C adapter, I don't know of anything that can take that 19v output and convert it to a proper USB-c sensing voltage. Maybe we'll see more of that sort of thing.
N.Y.Cab
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Re: Charging a New Dell USB C Laptop Via Old Dell Charger

Post by N.Y.Cab »

My Dell laptop is connected to an external monitor via USB C most of the time so the old adapter is rarely ever needed. In a pinch, I would rather grab a MacBook adapter instead of a dedicated one for Dell.
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Re: Charging a New Dell USB C Laptop Via Old Dell Charger

Post by junior »

If Dell officially sells adapters it might be okay, but otherwise I'd play it safe and only use USB stuff with USB devices.

The issue is you want the device plugged into your USB C socket to follow the USB C standard to make sure nothing breaks.
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enad
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Re: Charging a New Dell USB C Laptop Via Old Dell Charger

Post by enad »

arf1410 wrote: Mon Nov 21, 2022 6:27 pm just got a new Dell laptop, that has USB-C charging only, not the normal Dell Barrel plug used for the last 20 years. I've got a handful of those old chargers around, and was thinking I could pick up some cheap barrel to USB C adapters for under $10 bucks. Seems like the few I could find (including at Dell.com) are sold out, and were a bit expensive for what they seem to be. I can find some cheap ones on eBay.. but those concern me a bit.

Is the issue more complex than a simple adapter? Both the old, and new chargers, seem to output the same voltage, and amps.
Here's a solution for your that comes with a 30% coupon you can clip and checkout for under $16

Are you saying your Dell laptop did not come with a charger?
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