Thank you for contacting Plugable support! Sorry to hear about this issue. I’d be more than happy to assist you.
Sorry for our delayed reply over the holidays! Most Dell systems typically come with power adapters around 45 watts, but a higher end system like yours probably shipped with a 90 or even 130w power adapter knowing common wattages Dell uses. Our UD-ULTC4K USB-C dock and TBT3-UDV Thunderbolt 3 dock can output 60 watts of power over USB-C Power Delivery which is a charging standard used by both USB-C and by extension, Thunderbolt 3.
Since the docks likely output less power than the stock charger the system may not be able to run from that, and it won’t accept charging from that port. There are docks coming out that can offer more power, typically 85w is the next step up, but even then that’s often not enough.
Unfortunately while USB-C and Thunderbolt 3 technologies develop over time we’re in a state of flux where not everything is 100% compatible. I recommend running the dock with your system in addition to connecting the stock Dell charger - it won’t damage the system as it will not be accepting a charge from the dock.
Please don’t hesitate to let us know of other questions.
Thanks again for contacting Plugable support and best wishes!
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