However, new equipment can be a little overwhelming to get started with, especially a power supply, which can damage your projects in the worst case if the current and voltage are not set correctly before use. 

To configure the power supply correctly, it is important to know what it offers. The table below lists its technical specifications. 

TECHNICAL SPECIFICATIONS FOR THE ZK-DP3D USB-POWERED POWER SUPPLY

SETTING UP THE ZK-DP3D

Below, we explain how to set the desired voltage, current, and fast charging protocols. There is also a video giving an overview of the power supply.

SETTING THE VOLTAGE

Press the rotary knob and the voltage symbol v on the top display line will begin to flash. Turn the knob to change the voltage, and check the displayed value before enabling the output. The adjustment resolution is 0.01 V. Once the desired voltage is selected, press the knob to save it.

SETTING THE CURRENT

After pressing the knob following voltage adjustment, the current symbol A on the lower display line will flash. You can now set the maximum current your system is allowed to draw. Turning the knob left increases the current setting and turning it right decreases it. The stated adjustment precision is +-0.001A. Once the desired maximum current is selected, press the knob.

MONITORING

While using the power supply, you can monitor current draw, power, ampere-hours, operating time, input voltage, and temperature. The image below shows how turning the knob to the right displays current, power, ampere-hours, and hours in that order. Turning it left lets you monitor input voltage and temperature.

The temperature reading tells you how hot the ZK-DP3D gets. The unit also monitors this temperature itself and automatically switches off if it becomes too hot, using its built-in overtemperature protection.

FAST CHARGING PROTOCOL DETECTION

ZK-DP3D has a built-in function that checks the source you connect your ZK-DP3D to for high-power protocols. If it detects one of the following protocols, it enables it, allowing you to reduce the current flowing through the ZK-DP3D power supply:

• QC2.0
• Qc3.0 
• AFC
• FCP 
• SCP

Example of Fast Charging Protocol Detection:

Let us take an example with a Mi Power Bank 2S 10000 mAh power bank. Normally it delivers 5v, but it also supports high-power protocols. When the ZK-DP3D is connected to the power bank, it checks for protocols and detects support for voltages of 12V, 9V, or 5V.
The ZK-DP3D then sets the voltage itself using one of these protocols. This is beneficial because a higher voltage means less current is needed to deliver the same power.
A lower current results in less heat dissipated in the ZK-DP3D. The formula below shows how the relationship between current and the resistance in the ZK-DP3D produces heat. On the ZK-DP3D you can always monitor its temperature, which gives a useful indication of whether significant power is being dissipated.

The formula is derived from Ohm’s law, which you can read more about here: eBits Ohm’s Law if you want a better understanding of voltage, current, resistance, and power.