How much current you may take
The listing says 1.5 A in one place and 3 A in another. Both are describing the charger, not the board — and the only number you are entitled to without measuring is 500 mA.
The charger has a resistor too
You know your side of the divider: 5.1 kΩ from CC to ground. The source's side is a pull-up towards its own 5 V, and the value it chooses is how it announces how much current it has.
Three values, fixed by the specification:
| The source fits | It is offering | CC then sits at |
|---|---|---|
| 56 kΩ | 500 mA (900 mA on a USB 3.0 port) | about 0.42 V |
| 22 kΩ | 1.5 A | about 0.94 V |
| 10 kΩ | 3.0 A | about 1.69 V |
Those voltages are just Ohm's law on the two resistors across 5 V. They are the source talking, and the CC pads on this board are where you can listen.
Nothing on this board is listening
That is the part worth being blunt about. The board pulls CC down and stops there. It does not measure the voltage, it has nothing to measure it with, and it has no way to stop your circuit from drawing more than the source offered.
So the honest default is the bottom row. Assume 500 mA unless you have gone and looked, because 500 mA is what every USB-C source offers and the only figure you get for free.
If you want to know rather than assume, the next chapter but one puts an ESP32 on the CC pad and prints the answer.
What the socket itself can take
The connector is a SHOU HAN TYPE-C 16PIN 2MD(073), and its specification rates it at DC 5 V, 3 A, over −25 to +85 °C, with an initial contact resistance of 40 mΩ or less and ten thousand insertion cycles. Three amps is also the most any 5 V USB-C source offers, so the socket is not the thing that will hold you back.
What will hold you back
Everything after the socket.
A 2.54 mm header pin, a breadboard contact and a 24 AWG jumper wire are all happy at a few hundred milliamps and all working hard at two or three amps. Breadboard contacts in particular are a spring gripping a pin, and their resistance is neither small nor predictable — it is where the volt goes missing when a circuit browns out for no visible reason.
Above about an amp, stop going through the breadboard. Solder wire to the VBUS and GND pads directly, use something thicker than a jumper lead, and keep it short.
About the listing
The Amazon description offers two different numbers — "recommended for currents up to 1.5 A" in one bullet and "commonly up to 1.5 A or 3 A with compatible sources" in another. Neither is a property of this board. They are describing what a charger might advertise, and the board has no part in it beyond being the socket the current arrives through. The number that belongs to the board is the connector's 3 A rating, and the number that belongs to your project is whatever the source is offering minus whatever your wiring wastes.
When it does not work
You are asking for more than the source is offering, or more than the wire can carry. Measure VBUS at the board with the load running, then again at the far end of your jumper wires — if the second reading is much lower, the wiring is the problem rather than the charger. A 24 AWG jumper is not a power cable.
Different sources advertise different currents, and the small one is probably offering the 500 mA default. Nothing on this board reads that advertisement, so nothing stops your circuit from trying to take more and browning out. Either use a source that offers more, or measure CC and find out what you have.
The socket is rated for it — SHOU HAN's specification says DC 5 V 3 A. Everything after the socket is the question. At 3 A a 2.54 mm header pin and a breadboard contact are working far harder than they were designed to, and a thin jumper wire will get warm. If you need amps, solder to the pads and use proper wire rather than going through a breadboard.
The board has almost nothing in it to get warm — two resistors carrying under a milliamp each and an LED. Heat means resistance where there should not be any, which on this board means a joint: a header pin that is not properly wetted, or a breadboard contact that has been stretched by a thick wire. Find the warm spot and resolder it.
The same two resistors that make the board work in one direction make it useless in the other.
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