The traction machine is one of the most important components in a traction elevator. It provides the mechanical power needed to move the elevator car and counterweight, while working together with the drive, controller, encoder, brake, and other control components.

Many modern elevators use gearless traction machines, particularly in applications where smooth operation, compact equipment, and efficient motor control are important.

As an elevator ages, the traction machine may eventually require repair or replacement. Bearings can wear, brakes can deteriorate, motors can develop electrical problems, and replacement parts for older machines may become increasingly difficult to source.

When this happens, gearless traction machine modernization can be an alternative to replacing the entire elevator.

FUJISJ-EM provides gearless traction machines and related elevator modernization components for replacement and upgrade projects.

What Is a Gearless Traction Machine?

A gearless traction machine drives the elevator sheave directly from the motor shaft without using a separate gearbox.

A typical gearless elevator traction system includes:

• Gearless traction machine
• Traction sheave
• Elevator motor
• Brake system
• Encoder
• VVVF drive
• Elevator controller
• Suspension ropes
• Counterweight

The motor directly rotates the traction sheave, which moves the elevator ropes and controls the movement of the car.

Compared with geared systems, gearless machines have a different mechanical configuration and are commonly used in medium- and high-rise elevator applications.

Why Consider Gearless Traction Machine Modernization?

A traction machine can operate reliably for many years when properly installed and maintained. However, aging equipment eventually becomes more difficult and expensive to maintain.

Modernization may be worth considering when:

• The machine is mechanically worn
• Motor insulation has deteriorated
• Bearings require frequent replacement
• Brake problems occur repeatedly
• The traction sheave is excessively worn
• Abnormal noise or vibration has developed
• Original replacement parts are difficult to obtain
• The machine is no longer supported
• Maintenance costs continue to increase
• The existing machine limits the performance of the elevator

The important point is that age alone does not determine whether a traction machine should be replaced. Its actual condition and compatibility with the rest of the elevator system should be evaluated.

What Are the Signs of a Failing Gearless Traction Machine?

1. Unusual Noise

A gearless machine should operate with controlled and predictable mechanical noise.

New or increasing noise may indicate problems with:

• Bearings
• Motor
• Brake
• Traction sheave
• Mounting
• Mechanical alignment

The exact cause should be identified before deciding whether the machine needs replacement.

2. Excessive Vibration

Unusual vibration can affect passenger comfort and may indicate mechanical or electrical problems.

Possible causes include:

• Bearing wear
• Motor imbalance
• Traction sheave problems
• Installation issues
• Brake-related problems
• Motor control problems

Because vibration can originate from different parts of the system, proper diagnosis is important.

3. Brake Problems

The brake is a critical part of the traction machine assembly.

Warning signs can include:

• Abnormal brake noise
• Delayed brake release
• Difficult brake adjustment
• Excessive wear
• Repeated brake-related faults

A brake problem does not necessarily mean the complete traction machine must be replaced, but it should be evaluated carefully.

4. Motor Temperature Problems

Abnormal motor temperature can result from several factors, including:

• Excessive load
• Electrical problems
• Poor ventilation
• Bearing problems
• Incorrect drive parameters
• Motor aging

Repeated overheating should not simply be treated as a minor maintenance issue.

5. Increasing Maintenance Requirements

An aging machine may continue to operate but require increasingly frequent maintenance.

When technicians are repeatedly replacing bearings, repairing brakes, troubleshooting motor problems, or sourcing discontinued components, replacing the machine may become a more practical long-term solution.

Should You Repair or Replace the Traction Machine?

This is one of the most important decisions in a modernization project.

Repair May Be Suitable When:

• The machine remains mechanically sound
• Replacement parts are available
• The motor performs normally
• Bearings can be replaced economically
• The brake system remains serviceable
• Maintenance costs are still reasonable

Replacement May Be Better When:

• Major components are severely worn
• The machine is obsolete
• Spare parts are difficult to obtain
• Repeated repairs have not solved the problem
• The motor has serious electrical deterioration
• The traction sheave is excessively worn
• Long-term reliability is a priority

A professional inspection should determine the condition before making the final decision.

What Should Be Checked Before Replacing a Gearless Traction Machine?

A replacement machine should not be selected simply because its dimensions look similar to the original.

Important information includes:

Elevator Rated Load

The machine must be suitable for the required elevator load.

Rated Speed

Machine speed needs to match the elevator's operating requirements.

Motor Power

The motor capacity must be appropriate for the elevator configuration.

Traction Sheave

Check:

• Sheave diameter
• Rope configuration
• Rope diameter
• Groove configuration

Suspension Ratio

The roping arrangement affects the required machine performance.

Brake Configuration

The replacement machine must provide a suitable braking system for the application.

Encoder

The encoder and feedback system need to work correctly with the drive and controller.

Mounting

The physical installation and machine base need to be considered before replacement.

Drive and Controller

The new machine needs to work with the existing or upgraded control system.

Can a Gearless Traction Machine Be Replaced Without Replacing the Controller?

Yes, in some modernization projects.

If the existing controller and VVVF drive are still serviceable and compatible with the new traction machine, they may potentially remain in use.

However, the following should be checked:

• Motor parameters
• Encoder
• Drive capacity
• Control mode
• Brake signals
• Feedback system
• Communication
• Parameter settings

If the existing drive is obsolete or cannot properly control the replacement machine, it may be more practical to upgrade the drive at the same time.

Should the VVVF Drive Be Replaced With the Gearless Machine?

Not necessarily.

There are two common approaches.

Traction Machine Only

This approach may be appropriate when:

• The drive is relatively new
• The controller is reliable
• The encoder is compatible
• The replacement motor matches the control system

Traction Machine + Drive

A combined upgrade may make more sense when:

• The drive is also obsolete
• Motor control is unstable
• Drive faults are increasing
• The existing drive cannot support the replacement motor
• Improved ride quality is a major objective

The best solution depends on the condition of the complete drive system.

What About the Encoder?

The encoder is an important part of a gearless elevator system because it provides feedback used for motor control and positioning.

Before replacing the traction machine, check whether the existing encoder can be used with the new machine and drive.

Important specifications may include:

• Encoder type
• Resolution
• Signal format
• Mounting
• Shaft configuration
• Feedback interface

An incompatible encoder can cause problems such as speed faults, poor leveling, or unstable operation.

For this reason, encoder compatibility should be considered before ordering the replacement machine.

What Is Involved in a Gearless Traction Machine Replacement?

A typical modernization project may include several stages.

1. Existing Equipment Assessment

Record the original machine information and inspect its mechanical and electrical condition.

2. System Compatibility Review

Check the motor, drive, controller, encoder, brake, ropes, and installation configuration.

3. Replacement Machine Selection

Choose a machine with suitable performance and mounting requirements.

4. Mechanical Installation

The existing machine is removed and the replacement machine is installed according to the project requirements.

5. Electrical Connection

Motor, brake, encoder, and other relevant electrical connections are completed.

6. Drive Configuration

Motor and encoder parameters are configured according to the replacement machine.

7. Testing and Commissioning

The elevator is tested for:

• Direction
• Acceleration
• Deceleration
• Stop accuracy
• Floor leveling
• Brake operation
• Encoder feedback
• Ride quality
• Fault response

The elevator should only return to passenger service after the required testing and inspection have been completed by qualified professionals.

Benefits of Gearless Traction Machine Modernization

Improved Reliability

A new traction machine can eliminate problems caused by severely worn or obsolete mechanical and electrical components.

Better Ride Performance

When properly matched with the drive and controller, a modern traction machine can contribute to smoother acceleration, deceleration, and stopping.

Reduced Maintenance Problems

Replacing an aging machine can reduce recurring repairs related to bearings, motor components, brake systems, and other worn parts.

Better Parts Availability

A current machine platform can make future maintenance and replacement-part sourcing easier.

Potential Energy Benefits

Modern permanent-magnet synchronous gearless machines can offer high efficiency, although actual energy savings depend on the complete elevator system and operating conditions.

Extended Elevator Service Life

If the hoistway, car, rails, doors, and other major components remain suitable, replacing the traction machine can extend the practical service life of the elevator.

Permanent Magnet Gearless Traction Machines

Many modern gearless elevator machines use permanent magnet synchronous motor (PMSM) technology.

PMSM gearless machines can offer:

• High motor efficiency
• Compact construction
• Direct-drive operation
• Precise speed control
• Low-speed torque characteristics suitable for elevator applications

However, the motor must be correctly matched with the VVVF drive, controller, and encoder.

The fact that a machine is labeled "gearless" does not automatically mean it can replace every other gearless machine.

How to Choose a Gearless Traction Machine

When selecting a replacement, start with the existing elevator specifications rather than choosing by appearance.

Check:

Specification	Why It Matters
Rated load	Determines required machine capacity
Rated speed	Must match elevator operating requirements
Motor power	Determines drive and motor requirements
Rope diameter	Must match the traction sheave
Sheave diameter	Affects traction and installation
Roping ratio	Influences machine requirements
Encoder	Must be compatible with control system
Brake	Must meet system requirements
Mounting dimensions	Determines installation compatibility
Drive	Must properly control the motor
Controller	Must communicate with the drive/system

Providing complete technical information before purchase can significantly reduce compatibility problems.

Common Mistakes When Replacing a Gearless Traction Machine

Choosing Only by Motor Power

Two machines with the same rated power may have very different specifications.

Load, speed, sheave, rope, encoder, brake, and mounting all matter.

Ignoring the Existing Drive

The drive must be capable of controlling the replacement motor correctly.

Forgetting the Encoder

An encoder mismatch can prevent the elevator from operating correctly.

Assuming the Existing Mounting Will Fit

The replacement machine may have different dimensions or mounting requirements.

Replacing the Machine Without Checking the Ropes

The rope and traction sheave configuration must be compatible.

Focusing Only on Initial Price

The cheapest machine may not be the most economical choice if installation modifications or additional components are required.

How Much Does Gearless Traction Machine Modernization Cost?

There is no fixed price for every project.

The total cost depends on:

• Machine capacity
• Motor type
• Rated speed
• Traction sheave
• Encoder
• Brake configuration
• Mounting requirements
• Drive compatibility
• Controller compatibility
• Installation
• Testing and commissioning

A straightforward machine replacement can have a very different cost from a project involving a new machine, VVVF drive, controller, encoder, and other modernization components.

The modernization scope should therefore be determined after evaluating the existing elevator.

How Long Does a Gearless Traction Machine Replacement Take?

The installation period varies considerably.

Factors include:

• Existing machine-room configuration
• Machine size and weight
• Accessibility
• Mounting modifications
• Electrical work
• Drive configuration
• Encoder installation
• Testing requirements

A project should include sufficient time for installation, adjustment, testing, and commissioning, rather than considering only the physical machine replacement.

For commercial buildings, planned downtime should also be coordinated with building management.

How FUJISJ-EM Supports Gearless Elevator Modernization

A traction machine is rarely an isolated replacement.

The machine needs to work with the elevator's VVVF drive, controller, encoder, brake, ropes, and existing mechanical configuration.

FUJISJ-EM supplies gearless traction machines and related elevator modernization components, including:

• Gearless traction machines
• PMSM elevator motors
• VVVF drives
• Elevator controllers
• Control boards
• Encoders
• Door operators
• Door controllers
• Safety components
• Other elevator modernization parts

For a replacement project, customers can provide the existing traction machine nameplate, motor specifications, rated load, elevator speed, rope diameter, sheave information, encoder model, drive model, and equipment photos.

This makes it easier to determine whether a machine-only replacement is suitable or whether additional components should be upgraded.

Conclusion

Gearless traction machine modernization can be a practical solution for extending the service life of an aging elevator when the existing machine has become unreliable, obsolete, or difficult to maintain.

The replacement should never be selected based only on motor power or physical appearance. Rated load, speed, motor characteristics, traction sheave, ropes, encoder, brake, drive, controller, and mounting conditions all need to be considered.

In some projects, replacing only the traction machine is sufficient. In others, upgrading the VVVF drive, encoder, or controller at the same time provides a more reliable long-term solution.

FUJISJ-EM supports elevator modernization with gearless traction machines, PMSM motors, VVVF drives, controllers, encoders, door systems, and other critical components, helping elevator professionals develop compatible replacement solutions for aging equipment.