The RoboClaw’s three onboard status LEDs (ERR, STAT1 and STAT2) signal three classes of problems: faults, warnings and notices. This guide explains how to read the LED blink codes and how to troubleshoot the current, voltage and temperature conditions behind the most common errors.
Things don’t always go as planned when operating a robot, and the RoboClaw features a set of onboard LEDs that are used to indicate problems with the controller and with your hardware. The LEDs indicate three classes of problems: faults, warnings and notices.
Locating the Status LEDs
The status LEDs are located along the edge of the board, right next to the buttons. The LEDs are labeled ERR, STAT1 and STAT2.
Faults
The first class of errors are faults. When a fault occurs, the RoboClaw disables all motor outputs and halts operation. The controller requires either a reset or, in the case of a non-latching E-Stop, clearing of the fault condition to resume operation. There are unique LED patterns for each of the faults listed in the table below. Note that the Velocity Error and Position Error faults trigger when the configured PID error limits are exceeded.
| LED Indication | Condition | Controller Action |
|---|---|---|
| All three LEDs lit. | E-Stop | Motors are stopped by braking. |
| Error LED blinks once with short delay. Other LEDs off. | Temperature over 100C | Motors freewheel while condition exists. |
| Error LED blinking two times. | Logic battery high | Motors freewheel until reset. |
| Error LED blinking three times. | Logic battery low | Motors freewheel until reset. |
| Error LED blinking four times. | Velocity error fault | Triggers if the velocity error limit is exceeded. |
| Error LED blinking five times. | Position error fault | Triggers if the position error limit is exceeded. |
Warnings
Warnings are the second class of errors. In the case of a warning condition, motor power is either limited or fully stopped depending on the warning. With warnings, the Error LED stays lit to alert you to the problem. There are not unique codes for each warning condition.
| LED Indication | Condition | Controller Action |
|---|---|---|
| Error LED lit while condition is active. | Temperature over 85C | Motor current limit is recalculated based on temperature. |
| Error LED lit while condition is active. | Over current | Motor power is automatically limited. |
| Error LED lit while condition is active. | Main battery high | Motors freewheel while condition exists. |
| Error LED lit while condition is active. | Main battery low | Motors freewheel while condition exists. |
| Error LED lit while condition is active. | M1 or M2 home | Motor is stopped and encoder is reset to 0. |
Notices
The third class of errors is the notice. Currently there is only one condition that will trigger a notice.
| LED Indication | Condition | Controller Action |
|---|---|---|
| All three LEDs cycle on and off in sequence after power up. | RoboClaw is waiting for new firmware | RoboClaw is in boot mode. Use BasicMicro Motion Studio to clear the condition. |
Troubleshooting Current
The RoboClaw will reduce power to one or both motors if an overcurrent condition occurs. A multimeter can be used to check the current being pulled by your system. You can also check the amount of current being pulled by each motor in BasicMicro Motion Studio. Choose “PWM Settings” in the left hand pane; from here you can operate the motors via the sliders and view the current for each motor at the top of the window.
Another thing to check are the maximum current settings in BasicMicro Motion Studio. These can be viewed by selecting “General Settings” from the left hand side of the window and then finding the “Motors” (1) section. The setting for one or both motors may be set too low for your application. Things to look out for are driving too heavy of a load or using motors that are not suitable for the motor controller you have selected. These problems can be solved by changing the load applied to the motors, changing out your motors for more suitable ones, or moving to a motor controller that will tolerate the current drawn by your setup.
Figure 3: Location of the motor current settings (1) in the General Settings screen of BasicMicro Motion Studio.
Troubleshooting Voltage
Voltage errors can occur when the main battery voltage is too high or too low. The same problem can present itself with the logic battery if one is being used. You can use a multimeter to check the voltage of either battery. If the voltage of either battery is within bounds for operation with the RoboClaw, you will also need to check the settings for both batteries in the “Battery” (1) section of the General Settings screen in BasicMicro Motion Studio. The main battery voltage and logic battery voltage can also be seen after you have connected the RoboClaw in BasicMicro Motion Studio.
Figure 4: Location of the battery voltage settings (1) in the General Settings screen of BasicMicro Motion Studio.
Troubleshooting Temperature
The RoboClaw will indicate a temperature warning at 85C (185F) and a temperature fault at 100C (212F). The temperature can be read via serial commands or viewed directly in BasicMicro Motion Studio, outlined in Figure 5. The most common causes of a temperature error are:
- Inadequate cooling, such as no air flow around the controller
- Ambient temperatures that are too high, which keep the board from shedding heat effectively no matter the load
- Too big of a load, such as a large, high-current motor
An overloaded controller is fixed the same way as a current error: reduce the load, change motors, or move up to a larger controller.
Boards with an onboard fan depend on it for cooling: check that the fan is running and unobstructed. For the 2x15A, 2x30A and 2x45A, the case and fan combination covered in Installing the RoboClaw Case and Fan adds firmware-controlled active cooling.
Figure 5: The RoboClaw’s temperature display, outlined in the General Settings screen of BasicMicro Motion Studio.
Next Steps
You should now understand how the RoboClaw’s LEDs are used to indicate problems with your robot, and that the majority of these problems trace back to the power supplies for the RoboClaw and the motors used with it. RoboClaw Basics covers the fundamentals of setting up and using a RoboClaw, and Configuring RoboClaw Battery Settings walks through setting the voltage limits that prevent many of the errors covered here.
