Mini-Project 1: A Single-Motor Test Stand from Battery to Spin

A motor test stand is the single most useful thing an electrical sub-team can build. It lets you prove a motor, a controller, and your code without the whole robot. Here is the full bill of materials and build order.

BOM: MK ES17-12 12V SLA battery (12V, 18Ah; sold by REV as REV-19-2487 and by AndyMark), an Anderson SB-50 connector pair, a Cooper Bussmann 120A main breaker (CB185-120), a power distribution device (REV PDH REV-11-1850 or CTRE PDP), a roboRIO, a REV SPARK MAX, one NEO/Kraken motor, a 40A ATO/AT2-style auto-resetting breaker (the PDH takes ATO blade-style breakers, e.g. the REV ATO breaker or AndyMark am-4947; the classic Snap-Action MX5-A fits the legacy CTRE PDP instead), plus 6 AWG, 12 AWG, and 18 AWG wire.

Build order (mirrors WPILib's wiring guide):

1. Crimp a ring terminal to the red lead of the SB-50 connector, then run 6 AWG from the battery connector to the main 120A breaker. The main breaker is the only thing that touches the battery directly.
2. Run 6 AWG from the breaker's load terminal to the PD's positive input, and 6 AWG from the SB-50 negative straight to the PD negative. Wire gauge here is mandated by rule R609 (6 AWG / 16 mm minimum on the battery-to-breaker-to-PD path).
3. Power the roboRIO from a dedicated PD output through 18 AWG to the roboRIO's power input. On the PDH this is a fused low-current channel; on the PDP use the dedicated roboRIO connector.
4. Insert a 40A ATO/AT2-style breaker into a high-current PDH channel and run 12 AWG to the SPARK MAX +/- input terminals. R622 requires 12 AWG for any 31-40A circuit.
5. Wire the motor output: motor red to controller M+, black to M- (for a NEO over the SPARK MAX's screw terminals).
6. CAN: yellow=CANH, green=CANL, daisy-chained roboRIO -> SPARK MAX -> PD.

Smoke test: Before connecting the battery, verify polarity with a multimeter at the PD input pads. Then plug in. The roboRIO Power LED should go solid green.

Minimal code to spin it (WPILib + REVLib 2025):

import com.revrobotics.spark.SparkMax;
import com.revrobotics.spark.SparkLowLevel.MotorType;
import com.revrobotics.spark.config.SparkMaxConfig;
import com.revrobotics.spark.config.SparkBaseConfig;
import com.revrobotics.spark.SparkBase.ResetMode;
import com.revrobotics.spark.SparkBase.PersistMode;

public class Robot extends TimedRobot {
  private final SparkMax motor = new SparkMax(5, MotorType.kBrushless);
  private final XboxController stick = new XboxController(0);

  public Robot() {
    SparkMaxConfig cfg = new SparkMaxConfig();
    cfg.smartCurrentLimit(40)
       .idleMode(SparkBaseConfig.IdleMode.kBrake);
    motor.configure(cfg, ResetMode.kResetSafeParameters,
                    PersistMode.kPersistParameters);
  }

  @Override public void teleopPeriodic() {
    motor.set(stick.getLeftY());
  }
}

Note that IdleMode lives on SparkBaseConfig in REVLib 2025, and the CAN ID 5 in the constructor must match the ID you set in the REV Hardware Client. Keep this stand intact all season as your go-to debug rig.