In my experience working with OEMs, installers, and project buyers, tubular motor noise is one of the most misunderstood problems in screens, and automated shading systems. Many people treat noise as a “quality issue” or a random defect, when in reality it is almost always the mechanical result of selection errors, installation tolerance problems, or long-term wear that could have been predicted earlier.

What makes tubular motor noise tricky is that it often starts subtly. A system that sounds acceptable during commissioning can become objectionably loud months later, once loads shift, bearings wear, or misalignment begins to amplify vibration. By the time end users complain, the project risk and service cost are already locked in.

In this article, I want to explain tubular motor noise the way engineers do: by linking noise symptoms to mechanical causes and corrective actions. I will also explain which noise problems are fixable in the field, which ones signal unavoidable replacement, and how better motor selection decisions upfront can prevent noise entirely. My goal is to help both technical teams and procurement decision-makers reduce risk, not just treat symptoms.

JIECANG tubular motor

What Is Tubular Motor Noise?

When customers say a motor is “noisy”, they often mean very different things. From an engineering standpoint, I always separate normal operating noise from abnormal mechanical noise, because only the latter indicates a real problem.

Normal operating noise is the steady hum or low-frequency whir generated by the motor's electromagnetic field and gear train under load. This sound is consistent, repeatable, and usually masked once the system is installed inside a tube or shutter box.

Abnormal noise, on the other hand, is irregular, increasing over time, or clearly mechanical in character. It may present as vibration, grinding, clicking, or impact sounds. These noises are not cosmetic issues—they are energy losses caused by misalignment, friction, or structural resonance, and they almost always point to a design or installation fault.

Understanding this distinction is the first step in deciding whether a system needs adjustment, repair, or full replacement.

Common Types of Tubular Motor Noise

1. Vibration Noise

Vibration noise is the most common complaint I encounter in the field. It typically sounds like a low-frequency buzzing or rattling that resonates through the tube, brackets, or surrounding structure. Importantly, the motor itself may not be defective at all—the noise is often caused by mechanical vibration being transferred into the building structure.

From a mechanical perspective, vibration noise occurs when the rotating mass of the motor is not concentric with the tube, or when torque pulsations excite a structural resonance. Even small eccentricities can generate surprisingly loud noise once amplified by long tubes or lightweight shutter housings.

2. Grinding or Friction Noise

Grinding noise is sharper and more concerning. It often indicates direct mechanical contact where there should be clearance, such as worn bearings, damaged gear teeth, or interference between the motor body and the tube.

I treat grinding noise as a warning sign. While short-term operation may still be possible, continued use accelerates wear and can lead to overheating or seizure. Unlike vibration noise, grinding noise rarely resolves itself through adjustment alone.

3. Clicking or Impact Noise

Clicking or impact noise usually appears intermittently, often at startup, stopping, or direction reversal. This type of noise is commonly caused by backlash in the gear system, loose mounting brackets, or axial play that allows the motor to shift under load.

In some cases, clicking is related to torque being right at the limit of the motor's capability. Each click is the system mechanically “catching up” to the load, which tells me the torque margin is insufficient.

Root Causes of Tubular Motor Noise (Engineering Perspective)

1. Incorrect Torque Selection

One of the most common mistakes I see is undersized torque selection. When a tubular motor operates too close to its rated torque, it produces higher electromagnetic ripple and mechanical stress in the gearbox. That stress manifests as vibration, clicking, and long-term gear wear.

What many buyers miss is that torque rating is not just about whether the motor can lift the load—it's about how smoothly it can do so. A motor running at 80–90% of its rated torque will always be noisier over time than one operating at 50–60%.

2. Installation Misalignment and Tolerance Issues

Tubular motors are extremely sensitive to alignment. Even a small angular or axial misalignment between the motor shaft, adapter, and tube creates cyclic side loads on the bearings. Those loads turn directly into vibration noise.

I have measured cases where a misalignment of less than one millimeter resulted in a dramatic increase in audible noise once the system reached operating speed. This is why installation quality often matters more than motor brand.

3. Motor–Tube Compatibility Problems

Another overlooked issue is motor diameter versus tube inner diameter compatibility. If the motor body or adapter is too tight inside the tube, there is no room to absorb vibration. Any motor oscillation is transferred directly into the tube wall, which acts like a speaker.

Conversely, if the fit is too loose, the motor can shift under load, causing impact noise. Proper adapter selection and tube tolerance are not optional details—they are noise control measures.

4. Bearing Wear and Gear Degradation

Over time, bearings lose lubrication and gear teeth experience surface wear. As clearances increase, noise increases. What starts as a faint hum can turn into grinding or clicking after thousands of cycles.

In my experience, bearing-related noise almost never improves. Once wear reaches the point of audible noise, replacement planning should begin, especially for high-duty or safety-critical installations.

How Installation Quality Directly Affects Motor Noise

Installation quality is where many projects fail silently. I have seen excellent motors perform poorly simply because basic mechanical principles were ignored.

Bracket fixation is the first checkpoint. If mounting brackets are not rigidly fixed or are installed on flexible surfaces, vibration has nowhere to dissipate. The structure itself becomes part of the noise problem.

Concentricity is the second checkpoint. The motor shaft, tube, and end support must share a common rotational axis. Any eccentricity creates unbalanced forces that scale with speed and load.

Axial alignment is the third checkpoint. Excessive axial preload or clearance allows the motor to move longitudinally, which often produces clicking or knocking noises during direction changes.

When noise complaints arise, I always inspect installation tolerances before blaming the motor.

How to Reduce or Eliminate Tubular Motor Noise

Some noise problems can be corrected on-site, while others cannot. Knowing the difference saves time and money.

On-site adjustments are effective when noise is caused by bracket looseness, misalignment, or minor concentricity issues. Re-seating the motor, correcting adapter fit, and improving bracket rigidity can significantly reduce vibration noise.

However, when noise is caused by bearing wear, gear damage, or chronic overload, replacement is unavoidable. No amount of adjustment can restore lost material or eliminate internal clearance growth.

The key is early diagnosis. Addressing vibration noise early can prevent irreversible internal damage later.

When Motor Noise Indicates Replacement Is Required

I consider replacement mandatory when noise is combined with overheating. This combination tells me that friction losses are already high enough to threaten insulation life and safety margins.

Noise combined with unstable or jerky load movement is another red flag. It often indicates gear damage or torque saturation, both of which can lead to sudden failure.

In these cases, continued operation is not cost-effective. Field repair costs, downtime, and warranty risk quickly exceed the price of a new motor.

Tubular Motor Selection Guidelines to Avoid Noise Problems

Noise prevention starts long before installation. From a selection standpoint, I always recommend building in a torque margin of at least 30–50% above calculated load, especially for high-cycle applications.

Duty cycle matters just as much as torque. Motors designed for intermittent residential use will become noisy very quickly in commercial or industrial duty profiles. In real projects, tubular motor noise rarely exists in isolation—it is usually part of a broader shading system design issue involving control method, motor type, and application environment. I often recommend that engineers and specifiers step back and review the full system architecture using a smart shading motor selection guide, especially when projects involve mixed applications such as roller shades, blinds, or pergola systems.

AC and DC motors also differ in noise behavior. DC tubular motors generally offer smoother torque and lower acoustic output, especially at low speeds, while AC motors may produce more electromagnetic hum but offer simpler control.

Finally, compliance with CE and EN standards ensures that baseline noise and vibration limits are met, but compliance alone does not guarantee quiet operation in a poorly designed system.

Cost and Risk Perspective: Repair vs Replacement

Near the end of many projects, buyers ask me whether it's cheaper to fix a noisy motor or replace it. The answer depends on the root cause.

From a project risk standpoint, unresolved noise complaints often lead to reputational damage, delayed acceptance, and unexpected service costs. Preventing noise through proper selection and installation is always cheaper than managing it later.

Final Thoughts and My Recommendation

After years of dealing with noisy tubular motor projects, I can say confidently that noise is never random. It is always the mechanical result of how a motor was selected, installed, and operated over time. Treating noise as a symptom rather than a root problem leads to repeated failures and unnecessary cost.

If you are designing, sourcing, or installing tubular motors, I strongly recommend addressing noise at the selection and installation stages, not after complaints arise. When noise does appear, diagnose it mechanically and act decisively—either correct the structure or replace the motor before damage escalates.

If you approach tubular motor noise with engineering logic instead of guesswork, you will protect your project timelines, your margins, and your reputation.

FAQ

Is tubular motor noise normal?

A low, consistent operating sound is normal. Irregular, increasing, or mechanical noise is not.

What causes vibration in tubular motors?

Vibration is usually caused by misalignment, insufficient torque margin, or structural resonance.

Can poor installation cause motor noise?

Absolutely. Installation tolerance issues are one of the most common root causes of noise.

How loud should a tubular motor be?

Most quality tubular motors operate below typical ambient noise levels once installed, often under 50 dB depending on structure.

Does a higher torque motor reduce noise?

Yes, when properly selected. Higher torque margin reduces mechanical stress and vibration.

When should a noisy tubular motor be replaced?

When noise is linked to overheating, unstable motion, or confirmed bearing and gear wear.