Yaskawa SGMPH-15A4A6S Servo Motor: Specifications, Applications and Replacement Guide

The Yaskawa SGMPH-15A4A6S is a 1.5 kW AC servo motor from Yaskawa’s Sigma-II generation. Although newer Yaskawa servo families are now available, SGMPH motors are still found in CNC equipment, rotary tables, automated machinery and production lines that were originally designed around Sigma-II servo systems.

For maintenance teams, machine rebuilders and industrial buyers, the main question is often not simply whether a servo motor has the correct power rating. The complete model number, encoder type, shaft configuration and existing servo amplifier also need to match.

If you are sourcing this specific unit, see the Yaskawa SGMPH-15A4A6S servo motor product page for current availability and quotation information.

What Is the Yaskawa SGMPH-15A4A6S?

SGMPH is part of the Yaskawa Sigma-II servo motor family. The series was designed for compact industrial motion-control applications and was offered in several output ratings, including 100 W, 200 W, 400 W, 750 W and 1.5 kW.

The SGMPH-15A4A6S sits at the 1.5 kW end of this family.

Its basic configuration can be summarized as follows:

Yaskawa documentation identifies SGMPH as a Sigma-II product family rather than a Sigma-7 motor. The distinction matters when replacing an existing motor because newer SGM7-series specifications should not be assumed to apply directly to SGMPH units.

Understanding the SGMPH-15A4A6S Model Number

The model number contains useful information for identifying the motor.

In SGMPH-15A4A6S, the 15 designation indicates a rated output of 1.5 kW, while A identifies the 200 V power class. The model belongs to the SGMPH family and uses an incremental encoder configuration.

The shaft configuration is also important. This version uses a straight shaft with a key, which means a replacement should be checked against the existing coupling, pulley, gearbox or rotary-table connection before installation.

This is particularly important when purchasing older automation parts. Two motors from the same SGMPH family can have similar electrical ratings but different encoder, shaft, brake or sealing configurations.

Where Is the SGMPH-15A4A6S Used?

SGMPH motors were used in a wide range of industrial motion systems. The 1.5 kW SGMPH-15A4A6S is particularly relevant where a machine requires controlled positioning together with relatively high motor output in a compact servo package.

Typical equipment can include CNC machine accessories, indexing mechanisms, automated production machinery, positioning equipment, material-handling systems and rotary-table applications.

The model also appears in documentation for industrial NC rotary tables, illustrating why exact replacement demand still exists even though the SGMPH family belongs to an earlier Yaskawa servo generation.

For an existing machine, retaining the original motor configuration may sometimes be more practical than redesigning the entire motion system around a newer servo platform.

Why Is SGMPH-15A4A6S Still Searched for?

Industrial automation equipment often remains operational far longer than the commercial life cycle of its individual electronic and motion-control components.

A CNC machine or production line installed many years ago may still be mechanically sound, while a failed servo motor creates unexpected downtime. In these situations, maintenance teams frequently search the exact part number printed on the motor nameplate.

That makes SGMPH-15A4A6S a highly specific replacement-parts search rather than a general servo-motor search.

Using an identical or properly verified replacement may reduce the amount of mechanical and electrical modification required compared with immediately converting the machine to a completely different servo generation.

Is the SGMPH Series Discontinued?

Yaskawa currently categorizes SGMPH as a legacy Sigma-II product and no longer promotes the series in the Americas. Yaskawa has also published transition documentation covering migration from SGMPH Sigma-II motors to newer SGM7P Sigma-7 products.

This does not mean that an SGM7P motor can simply be installed in place of an SGMPH-15A4A6S without checking the system.

Servo-generation changes can involve differences in motor dimensions, amplifier compatibility, encoder architecture, cabling and commissioning requirements. A migration should therefore be treated as a system-level engineering decision rather than a simple part-number substitution.

SGMPH-15A4A6S Replacement: What Should You Check?

Before ordering a replacement, verify the complete motor nameplate rather than relying only on “SGMPH-15”.

The most important points are the complete part number, rated output, voltage class, encoder type, shaft configuration, brake or shaft-seal options, connector arrangement and the model of the servo amplifier already installed in the machine.

It is also useful to check whether the machine builder used a standard Yaskawa configuration or a customized OEM arrangement.

For example, an OEM machine may use the motor together with a specific coupling, rotary table, cable assembly or parameter set. Matching only the rated power does not guarantee that another 1.5 kW Yaskawa servo motor will work as a direct replacement.

SGMPH-15A4A6S vs Newer Yaskawa Servo Motors

Newer Yaskawa servo generations provide higher-resolution feedback, newer drive platforms and updated motion-control capabilities. However, that does not automatically make them drop-in replacements for Sigma-II equipment.

For a machine that needs to return to service quickly, sourcing the correct SGMPH configuration can avoid a larger retrofit.

For a machine undergoing a planned modernization project, moving to a newer Yaskawa servo platform may make more sense, particularly when the original drive, cables and other Sigma-II components are also becoming difficult to maintain.

The appropriate choice therefore depends on whether the objective is repairing the existing system or modernizing the complete servo system.

Can You Replace Only the Servo Motor?

Sometimes, yes.

If the existing servo amplifier, wiring and machine control system remain functional and the replacement motor has the correct specification, replacing only the failed motor may be the simplest approach.

However, compatibility should be verified before installation. Servo motors and amplifiers operate as a matched motion-control system, so an incorrect encoder or electrical configuration can prevent normal commissioning even when the mechanical dimensions appear similar.

When the original amplifier is also obsolete or faulty, it may be worth evaluating a complete servo-system migration instead of replacing components individually.

What Information Should You Provide When Requesting a Quote?

For faster identification, provide the full model number SGMPH-15A4A6S, clear photos of the motor nameplate, the existing servo amplifier model, machine manufacturer and model if known, and details of any brake, encoder, shaft or connector requirements.

These details help reduce the risk of supplying a visually similar but electrically or mechanically different SGMPH variant.

Buyers searching for the exact motor can check the Servo Motor SGMPH-15A4A6S product page for product information and availability.

Frequently Asked Questions

Is SGMPH-15A4A6S a Sigma-7 servo motor?

No. SGMPH belongs to Yaskawa’s Sigma-II servo motor generation. Sigma-7 uses later product families such as SGM7A, SGM7J, SGM7G and SGM7P.

What is the rated output of SGMPH-15A4A6S?

The rated output is 1.5 kW, approximately 2 HP.

What voltage is SGMPH-15A4A6S?

It belongs to the 200 V power-supply class.

What encoder does SGMPH-15A4A6S use?

This configuration uses a 13-bit incremental encoder.

Can SGM7P directly replace SGMPH-15A4A6S?

SGM7P is identified by Yaskawa as a successor family for SGMPH applications, but it should not be assumed to be a direct plug-and-play replacement. Mechanical dimensions, amplifier, encoder, cables and system configuration should all be checked before conversion.

Why buy an older SGMPH motor instead of upgrading?

For equipment already designed around Sigma-II hardware, replacing the failed motor with the correct SGMPH model can sometimes restore production with fewer changes. For machines undergoing broader modernization, upgrading the complete servo system may be more appropriate.

Final Considerations

The Yaskawa SGMPH-15A4A6S remains relevant because many machines using Sigma-II servo systems are still operating in factories today.

When sourcing a replacement, focus on the complete part number rather than only the motor power rating. Encoder type, voltage, shaft design, accessories and amplifier compatibility can all determine whether the motor is suitable for the existing machine.

For availability or replacement assistance, refer to the SGMPH-15A4A6S servo motor listing and provide the original motor nameplate information when requesting a quotation.