The REV Servo Hub uses LEDs to provide visual feedback about the device's status and individual channel states. Understanding these indicators helps diagnose issues and monitor system performance.
Important: These led patterns only apply to firmware version 24.0.0 and later
The main Status LED on the Servo Hub communicates the overall state of the device. Below is a table explaining the various patterns and their meanings:
Magenta Blinking
Anytime
The Servo Hub is powered on but not connected to a controller or the REV Hardware Client.
Blue Solid
Anytime
The Servo Hub is connected to the Communication established the REV Hardware Client.
Solid Cyan
Anytime
The Servo Hub is connected to a roboRIO or other CAN controller. â€
Green Solid
Anytime
The Servo Hub is connected to a Control Hub or other RS-485 controller. The number of blue blinks is the same as the Servo Hub's address. The factory default address is 3.
Orange/Cyan Blinking
Anytime
Battery Voltage is lower than 5.5V. Please check the Servo Hub's Power Supply. This fault will clear when the input voltage is raised above 6.5V.
Orange/Yellow Blinking
Anytime
A CAN fault has been detected. Verify CAN bus wiring and connections.
Orange/Magenta Blinking
Anytime
An overcurrent fault has occurred. Check the connected servos and reduce the load if necessary.
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Faults are not reported to logs when the Servo Hub is connected via RS485.
Each servo channel on the REV Servo Hub has its own dedicated LED, which provides feedback about the channel’s state and current PWM signal. Below is the meaning of each LED pattern:
Channel LEDs reflect the current state of the PWM signal, helping users verify servo behavior in real-time.
Disabled channels still show feedback via a blinking amber LED, making it easy to differentiate inactive channels.
Amber Solid
Anytime
The channel is at the center position (typically 1,500 µs pulse width).
Green Blinking
Anytime
The pulse width is between center and maximum (e.g., 1,500–2,000 µs).
Green Solid
Anytime
The channel is at the maximum position (e.g., 2,000 µs).
Red Blinking
Anytime
The pulse width is between center and minimum (e.g., 1,500–1,000 µs).
Red Solid
Anytime
The channel is at the minimum position (e.g., 1,000 µs).
Amber Blinking
Anytime
The channel is disabled. The signal pin is pulled low, and no PWM signal is being sent.
Quick Amber Blinking
Anytime
The channel is faulted. This can mean that either the device does not have sufficient power, neither the RoboRIO nor the Control Hub heartbeat is present, or the channel is experiencing an overcurrent event.
Amber Solid
Anytime
The servo is stopped (typically 1,500 µs pulse width).
Green Blinking
Anytime
The servo is running forward (e.g., 1,500–2,000 µs).
Green Solid
Anytime
The servo is running forward at maximum speed (e.g., 2,000 µs).
Red Blinking
Anytime
The servo is running in reverse (e.g., 1,500–1,000 µs).
Red Solid
Anytime
The servo is running in reverse at full speed (e.g., 1,000 µs).
Amber Blinking
Anytime
The channel is disabled. The signal pin is pulled low, and no PWM signal is being sent.
Quick Amber Blinking
Anytime
The channel is faulted. This can mean that either the device does not have sufficient power, neither the RoboRIO nor the Control Hub heartbeat is present, or the channel is experiencing an overcurrent event.
