The big picture
Every FRC robot runs the same core set of electronics, supplied in the Kit of Parts and governed by the FRC Game Manual, Section 8 (Robot Construction Rules). Understanding how the pieces fit together is the foundation for everything else in this branch.
Think of the system in five roles:
- The power source - a single 12V, ~18Ah Sealed Lead Acid (SLA) battery that can briefly supply over 180A.
- The power distributor - the power distribution device (PD), which splits battery power into protected branch circuits. Legal options are the REV Power Distribution Hub (PDH), the CTRE Power Distribution Panel (PDP / PDP 2.0), and, new for 2026, AndyMark Power Distribution.
- The brain - the NI roboRIO (currently roboRIO 2.0), a dual-core ARM Cortex-A9 processor plus a Xilinx FPGA that runs your code and the FRC safety system.
- The communication link - the Vivid-Hosting VH-109 radio (Wi-Fi 6E), which connects the robot to the Driver Station and the field.
- The muscles - motor controllers (Talon FX, SPARK MAX/Flex, Victor SPX, and others) that take low-power signals and switch high battery current to motors.
How signal and power flow
There are two separate networks on the robot:
- Power wiring carries high current. It runs from the battery, through the main 120A breaker, into the PD, then out through branch breakers to each motor controller and device.
- Control wiring carries low-current signals. The roboRIO commands motor controllers either over PWM (a simple pulse signal) or over the CAN bus (a digital network that daisy-chains many devices on two wires).
Rule R609 requires the high-current path - the battery, the Anderson SB connector pair, the 120A main breaker, and the PD - to be wired with 6 AWG copper wire or larger.
Why this matters
The most common reason a competitive robot fails on the field is not a software bug - it is an electrical fault: a loose connector, an undersized wire, a tripped breaker, or a brownout. The teams that win consistently treat wiring as a craft, not an afterthought.
Sources to bookmark
Key takeaways
- The FRC control system splits into power wiring (high current) and control wiring (low-current signals).
- Core components: 12V SLA battery, a power distribution device (PDH/PDP/AndyMark PD), roboRIO, VH-109 radio, and motor controllers.
- The main power path must use 6 AWG or larger copper wire per Game Manual rule R609.
- Most field failures are electrical, not software - wiring quality directly affects reliability.
Keep going
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Sources & corrections
This lesson is AI-assisted: drafted from primary sources, then reviewed and edited by hand. Errors still get through. When one is reported we fix it and write down what changed — publicly, in the corrections log.
Sources and further reading
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Lesson quiz
RequiredAll 4 right completes the lesson. Miss one and only that question comes back — anything you already answered correctly stays banked.
0 of 4 answered
01.In the FRC control system, which component runs the team's robot code and commands all the other hardware?
02.What nominal voltage does the FRC robot's Sealed Lead Acid battery supply to the control system?
03.What is the role of the power distribution device (PDH or PDP) in the control system?
04.Per rule R609, how must the high-current path (battery, connectors, main breaker, and PD) be wired?
Answer every question to submit.
All 35 lessons in Electrical & Wiring
- Not started:Mini-Project 1: A Single-Motor Test Stand from Battery to Spin
- Not started:Mini-Project 2: Current-Limited Drivetrain (CTRE and REV)
- Not started:Mini-Project 3: A Live Power-Monitoring Dashboard
- Not started:Mini-Project 4: A Switchable Channel for Lights and Vision
- Not started:Mini-Project 5: CAN Device Bring-Up with Tuner X and the Hardware Client