Very slow charge rate (~10-15W) via Thunderbolt 3 port on Swift 5 (SF514-54GT-77LB)

Brunnis
Brunnis Member Posts: 10

Tinkerer
edited November 2023 in 2020 Archives

I bought a Swift 5 (SF514-54GT-77LB, i7-1065G7, MX 250) a while ago. I also bought a CalDigit TS3 Plus Thunderbolt 3 dock. The dock is great, except that the laptop's state of charge slowly decreases during light usage. The dock can sustain 87W charging, which would be more than enough for this laptop even at full load.

I've checked the charge rate during light desktop usage and with low screen brightness and the average is 1.7W. Removing the dock cable, the discharge rate is -8.5W. This is a bit crude, but it shows the dock only charges by around 10W.

Connecting a Lenovo 65W USB-C charge (i.e. charging only, no USB/Thunderbolt) the laptop charges quickly and maintains 100% charge during use.

Does anyone have any theories on what might be happening?

Answers

  • billsey
    billsey ACE Posts: 34,246 Trailblazer
    edited May 2020
    I wonder if it's delivering too low of voltage. The Thunderbolt charging is supposed to allow charging at several different voltages, so the dock may not be putting as much in as your laptop expects. IIRC the SF514-54GT expects 20V at 65W, or just over 3A. If the dock is giving 12V at 3A instead, that drops your wattage to 36W instead of 65W...
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  • Brunnis
    Brunnis Member Posts: 10

    Tinkerer

    It only seems to be charging with ~10W, actually.

    Today I tested the dock on my colleagues high-end Dell Core i9 with Quadro T2000. It quickly charged the machine, even with the 4K display at full brightness.

    Something probably screws up in negotiating the power delivery with the Acer. Question is if it's the Acer or the dock acting up... Will be testing the Acer on a Dell Thunderbolt 3 dock in a few days.

  • Brunnis
    Brunnis Member Posts: 10

    Tinkerer
    @billsey Okay, so just tested my laptop with the Dell WD19TB 180W Thunderbolt dock. Same problem, or maybe even worse. Watching the charge rate via HWiNFO64, it appears it's not really charging at all. A discharge rate of approximately -10W is reported whether plugged in or not. For comparison, attaching the regular barrel connector, a charge rate of 40W is reported.

    Could anyone affiliated to or working at Acer please check if this laptop, SF514-54GT-77LB, actually supports being charged via a Thunderbolt 3 dock? So far, the evidence says no.
  • billsey
    billsey ACE Posts: 34,246 Trailblazer
    The right people at Acer to answer that aren't on the board, the only times we see Acer people it's the one that maintain the board. They can sometimes escalate to someone appropriate sometimes.

    Spec says:
    Thunderbolt Port
    • Up to 40Gbps Thunderbolt transmission
    • Support USB3.1 Gen 1/2 and Display port 1.4
    • System charging up to 15W
    • Needed additional flash memory
    That seems to say that it will only take up to 15W through the port, so what you are seeing is somewhat expected, just giving a longer run time, not reversing the discharge. The stock charger for your model is the 65W one, I believe, so you're as much as 50W short of full charging capacity when using the TB port.
    Click on "Like" if you find my answer useful or click on "Yes" if it answers your question.
  • Brunnis
    Brunnis Member Posts: 10

    Tinkerer
    That's very interesting info. It could mean that 15W is the expected charge rate, which matches with what I'm seeing. Then there's this publicly available info from Acer:

    https://www.acer.com/ac/en/AE/content/compare/NX.HLKEM.001-NX.HHZEM.001

    "USB Type-C port supporting:

    USB 3.1 Gen 2 (up to 10 Gbps)DisplayPort over USB-CThunderbolt 3USB charging 5 V; 3 ADC-in port 9 or 12 or 20 V; 45 W"
    This is a bit ambiguous to me. It seem sto state it supports 9V, 12V and 20V laptop charging via the Thunderbolt port at a rate of 45W. However, it also states 5V 3A for USB charging. However, I take the latter to be the capability of the port when charging connected devices from the laptop.

    This really needs to be cleared up by Acer.
  • billsey
    billsey ACE Posts: 34,246 Trailblazer
    edited May 2020
    That's weird... I wonder if they just have typos in their specs or if the version done for your locale is actually different, other than language changes. The ones I see when I search is NX.HLJSM.003 (the US version) or NX.HLJTA.001 (the Taiwan version), the ones you linked to are NX.HLKEM.001 (SF514-54GT-73EC) and NX.HHZEM.001 (SF514-54GT-73MX) which don't match either of the ones I see, yours is SF514-54GT-77LB which is shown on a Swedish site as NX.HHZED.007, which also doesn't match the links.. Normally the only difference between the numbers is the language, which typically changes the keyboard, the paperwork and almost nothing else.
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