Why Does a High-Protection Motor Not Have One “Best” IP Rating?

A high-protection motor does not have one universal IP rating. For industrial motors, IP65, IP66, IP67, and IP68 can all represent high protection, depending on the actual working environment.

What Does the IP Rating of a Motor Actually Mean?

When you select a motor for industrial equipment, you may naturally think that IP68 is always better than IP65. However, this is not necessarily the right way to choose a motor.

The IP code is defined under IEC 60529 and uses two digits to describe protection.

• The first digit indicates protection against solid objects and dust.
• The second digit indicates protection against water.

For industrial motors, IP65, IP66, IP67, and IP68 are commonly considered high-protection levels. But each level is designed for different environmental conditions.

For example, your equipment may only need protection from dust and rain. Another machine may need frequent high-pressure washing. A third application may occasionally fall into water, while another may operate underwater continuously.

These applications should not automatically use the same motor.

The important question is therefore not:

“What is the highest IP rating available?”

It is:

“What type of protection does my motor actually need?”

This difference can have a direct impact on motor cost, structure, heat dissipation, service life, and overall equipment design.

What Do IP45, IP54, IP55, IP65, IP66, IP67, and IP68 Mean for Motors?

When you select a motor for electrical equipment, automation systems, fans, pumps, conveyors, or industrial machinery, you may see IP45, IP54, IP55, IP65, IP66, IP67, and IP68 in the motor specifications.

These ratings do not simply represent whether a motor is "good" or "bad." They describe the motor's resistance to solid particles and water under defined test conditions.

For motors, the first number represents protection against solid objects, while the second number represents protection against water.

This gives us a more practical way to understand common motor protection levels:

Why Should You Choose the IP Rating Based on Your Application?

Imagine you are designing three different machines.

Case 1: Outdoor AGV or Logistics Equipment

Your AGV operates outdoors and may encounter rain, dust, mud, and occasional water spray.

In this situation, the motor may need strong dust protection and protection against water jets. A solution around IP65 or IP66 may be appropriate depending on the actual environment.

Choosing IP68 simply because it is a higher number could increase cost without providing meaningful additional value for your application.

Case 2: Industrial Cleaning Equipment

Now consider a cleaning machine that is washed frequently.

The motor may face water spray from multiple directions and repeated cleaning operations. In this case, water-jet protection becomes especially important.

An IP66 solution may therefore be more relevant than simply selecting IP67 based on the number.

The design should also consider connectors, cable outlets, seals, bearings, and other components. A high IP rating on the motor housing alone does not automatically make the entire machine waterproof.

Case 3: Equipment That May Temporarily Enter Water

Consider an industrial machine that may accidentally become submerged during operation, transportation, flooding, or cleaning.

Here, IP67 can become more relevant because the equipment needs temporary immersion protection.

But you still need to confirm the manufacturer's specified test conditions and your actual operating requirements.

Case 4: Continuous Underwater Operation

This is a completely different requirement.

If your motor is installed in equipment that operates underwater for extended periods, you need to evaluate an IP68 solution and confirm the specified immersion conditions with the motor manufacturer.

In this situation, sealing is only one part of the engineering problem. Pressure, cable entry, shaft sealing, corrosion, bearings, insulation, heat dissipation, and long-term reliability may all need to be considered.

Does a Higher IP Rating Always Mean a Better Motor?

No.

A higher IP rating means a different level or type of environmental protection under the applicable test conditions. It does not mean the motor is automatically more suitable for your equipment.

This is particularly important for B2B motor purchasing.

Suppose your equipment only requires protection against dust and rain. If you select an unnecessarily high-protection motor, you may be paying for protection that your machine never uses.

At the same time, choosing an IP rating that is too low can expose the motor to water or dust ingress, potentially affecting electrical insulation, bearings, internal components, and service life.

The better approach is to balance:

Protection requirements + motor performance + operating environment + service life + budget.

This is where application-based motor customization becomes valuable.

How Can You Determine the Right IP Rating for Your Motor?

Before asking a motor supplier for a quotation, describe the actual working environment rather than simply asking for an “IP68 motor.”

You should consider several questions:

1. How Much Dust Will the Motor Face?

Is the motor installed in a clean factory, a dusty workshop, an agricultural environment, or an outdoor construction site?

Dust exposure can significantly affect the protection requirements.

2. What Type of Water Exposure Is Expected?

Is the motor exposed to:

• Rain?
• Water spray?
• Powerful water jets?
• Frequent washdown?
• Temporary immersion?
• Continuous immersion?

These conditions can lead to very different IP requirements.

3. How Long Will the Motor Be Exposed?

A motor that occasionally gets wet has a different requirement from one that operates in a permanently wet environment.

Duration matters, especially when considering immersion protection.

4. What Is the Motor's Installation Position?

The motor's orientation, shaft position, cable outlet, connector structure, and surrounding equipment can all influence the practical sealing design.

5. What Is Your Budget?

This is often overlooked.

A motor is only one part of your complete equipment cost. If IP65 can reliably meet the actual requirements, there may be little reason to pay for a much more demanding protection solution.

On the other hand, if the equipment has a high replacement cost or operates in a harsh environment, investing in the appropriate protection level may help reduce maintenance and downtime.

How Does BG Motor Select a Protection Solution for Different Applications?

At BG Motor, the protection level is considered together with the customer's actual equipment and working conditions.

The company's documented customized brushless DC motor solutions can achieve protection levels up to IP68 depending on customer requirements. Other parameters can also be customized, including motor dimensions, shaft diameter and length, mounting holes, installation method, and insulation requirements.

This means that the goal is not simply to provide the highest possible IP number.

Instead, the motor should be designed around your equipment.

For example, if you are developing an AGV, cleaning machine, agricultural machine, logistics system, robot, or outdoor industrial device, you can provide information about the environment in which the motor will operate.

Your supplier can then evaluate the required protection level together with:

• Motor power
• Operating speed
• Voltage
• Motor dimensions
• Temperature
• Load
• Duty cycle
• Installation position
• Water and dust exposure
• Expected service life
• Target cost

This approach can help you avoid both under-protection and unnecessary over-engineering.

Why Is Application-Based Customization Better Than Simply Buying an IP68 Motor?

For an equipment manufacturer, the motor is not an independent product. It is part of the complete machine.

An unnecessarily high IP rating can affect the motor's structure and cost. More sealing requirements may also need to be considered together with heat dissipation and mechanical design.

At the other extreme, selecting insufficient protection can create reliability problems when the equipment enters actual operation.

This is why an experienced motor manufacturer should first understand where and how your motor will work.

For example:

Outdoor AGV

→ Dust + rain + occasional water spray
→ Evaluate IP65/IP66 requirements

Cleaning equipment

→ Frequent water jets and washdown
→ Evaluate IP66 requirements

Occasional immersion

→ Temporary underwater exposure
→ Evaluate IP67 requirements

Continuous underwater application

→ Long-term immersion
→ Evaluate IP68 and specified immersion conditions

The final selection should then be balanced against your required performance and target budget.