Actuators are some of the most important pieces in machines are they are responsible for converting energy into actual motion. And when they are working well, it can almost feel as if it’s just something that’s expected.
However, when a single actuator fails, the problem is quickly noticed in the entire machine. Maybe it slows down, starts being jerky, or just stops altogether.
It’s important for engineers and technicians to understand the various issues actuators commonly face and the practical solutions that can help teams minimise disruptions.
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Actuator not responding
When an actuator doesn’t respond, an entire system can stop working as maybe a damper remains fixed or a gate refuses to move. In automated environments, this can be quite significant as it can mean issues with airflow or fluid control, and it also affects the entire production timing.
In most cases, it’s usually caused by a power issue like a blown fuse or a tripped breaker. The culprit can also be low voltage or damaged cables as they can interrupt the flow of power. It’s also possible that the problem is an internal fault, such as a failed circuit board, but this is less common.
To fix it, start with a basic power check to know if the actuator is receiving the correct amount of power. You can also check the output from the controller to see if it matches what’s needed. From there, do a physical inspection of the cables to rule out power delivery issues.
In case these don’t help, you may need to examine the internal controls.
Mechanical performance issues
When you notice that the actuator is moving more slowly than usual, hesitates during operation, or produces some unexpected sounds, the issue is often mechanical strain.
It can be the result of normal wear and tear, misalignment, or increased load. All these can cause an actuator to wear down or have the mounting hardware loosen.
Start by checking the alignment to ensure the actuator and its associated components are properly mounted and connected. Even slight misalignment can cause issues due to uneven stress on various components.
Next, try to test the driven component separately if possible. Cleaning or servicing it can easily solve issues and improve performance.
Accuracy and control issues
Actuators are often expected to start and stop at specific positions as they also control the accuracy of the larger machine. When the movement starts losing accuracy, it can have a big impact in terms of temperatures, pressure, or the accuracy of the output.
The most common cause for these errors is a calibration drift as components can always drift slowly during operation. The deviations may be small, but they add up over time and quickly become noticeable during normal operations.
Another common culprit here is a position sensor that provides incorrect information. When the control system receives such feedback, it still adjusts anyway, introducing new errors.
To solve these issues, you can start by doing a recalibration of the various parts of the machine that may be inaccurate. You can then measure the feedback to see if it’s correct or if you have a sensor that may need replacement.
Preventing actuator problems before they start
It's always important to ensure that you have a proper maintenance schedule for your actuators. It will help you save time, reduce downtime, and extend the lifetime of your equipment. It’s especially important here as most mechanical problems develop slowly over time.
You can always start with routine visual inspection as these are the most common and can be solved without major stoppages. Look for things like loose bolts or damaged wiring. Wear and tear should also be a part of it, and you should also monitor electrical performance to ensure that power stays stable.
When buying replacement parts, ensure they are high-quality and then give them the recommended conditions. This will let the actuators perform reliably and make maintenance more manageable.
