The power distribution board or PDB distributes power to the parts of your build. Choosing the right PDB can be essential to the success or failure of your build. Lets dive into the important factors of a PDB to help you choose the right one.
This article is part of a series that covers the entire concept of quadcopter parts, how they work, and how they come together. For further reading, see the master article: Components & Anatomy of an FPV Quadcopter
A power distribution board serves as a hub allowing you to connect your battery and other electronics in your copter. The board features interconnected positive and negative terminals. Power from a battery connected to one set of terminals will be distributed out to all the other terminals. Often there will be specific input and output terminals to help with your build.
You will connect your battery and parts like your ESC's and Flight Controller to the PDB. This allows the battery to power your entire system. Observing polarity is crucial when connecting your power source and hardware to your PDB. Soldering wires on the wrong polarity terminal can result in frying parts of your build.
See this example wiring diagram to help you understand how the boards work:
These following features and specifications are important to consider when buying a PDB. These can make your life easier in the long run
A voltage regulator is a small chip that converts the input voltage of your battery to a lower output voltage. These regulators are also known as BEC's or Battery Elimination Circuits. These regulators can be integrated or add-ons. Most often you will find 5v or 12v regulated outputs on a PDB. Regulated outputs are used for powering things like flight controllers, radio receivers, cameras, video transmitters, race transponders, LED's and more. For in-depth reading on the topic, visit Analog's article on the topic.
The construction of a board will determine its supported current draw. Often this is declared through LiPo support. You should make sure that the PDB you buy can support the battery you plan to connect. As of current most boards support 2-4 cell LiPo support and its becoming more and more common to see up to 6s supported.
It's also important to consider the amp draw of your ESC's. If you plan on connecting 4 x 30A electronic speed controllers then you will need to support 120A through your PDB.
Take into consideration the number of output terminals. You will connect one ESC per motor to the PDB. That means you need a + / - terminal connection for each. If you're running a hexacopter, you'll need 6 positive and 6 negative terminals. A quadcopter will only need 4 each.
The location of these terminals becomes increasingly important for the ease of your build. Some boards feature all the ESC connections on one side, while others offer connections on each side of the board. Some offer outputs all around the board. Consider the location of the outputs and how you will organize your build.
The RROSD PDB + OSD is an example of a PDB with outputs on one side of the board:
PDB's are often combined or built into other hardware. Some are even custom built to support a specific flight controller by stacking or setting connections in specific locations. Some frames require specific PDB's or even build them in.
Recently brands have started to integrate components. One example is to integrate PDB's into flight controllers. On-screen displays also commonly have a built-in PDB. This can be a very convenient feature and something to consider.
Here at Controller Craft we catalog every drone product from around the industry. Visit the power distribution board section to browse the options available industry wide.
Hopefully this article helps you understand what power distribution boards are, how they work, and how to choose the right one. Please leave questions and comments below.
Last updated on February 6, 2017