Emerson FX-316 | Brushless Servo Drive Replacement

Description

Product Overview

The Emerson FX-316 is a positioning servo drive from Emerson’s legacy FX Series Motion Control platform. Unlike a conventional PLC output module, it combines several motion-control functions inside one drive: position control, digital I/O, motor feedback processing, servo amplification, and an integrated power supply. The FX architecture was designed for brushless servo motors, with Emerson’s DX motor family specifically referenced as a compatible motor platform.

For Emerson FX-316, the useful distinction is that the drive can execute motion sequences internally instead of depending entirely on a PLC to generate every positioning command. Available documentation describes up to 32 programmable indexes, with commands such as Stop, Jog, and Home available from a PLC, operator interface, or serial communication. The drive stores its programmed parameters in non-volatile memory, which is important when replacing an obsolete unit in a production machine.

The Emerson FX-316 also provides a relatively fast motion-control loop for its generation, with published technical references citing 1 ms motion-path planning and a 500 µs position update rate. A reported FX-316 configuration provides eight optically isolated inputs and four optically isolated outputs, while the broader FX family supports application modules for expanded I/O, memory, and specialized motion functions.

From a replacement standpoint, do not treat every FX-316 listing as technically equivalent. Some secondary sources incorrectly describe the model as a generic I/O module, while more specific references identify it as an Emerson FX Series brushless positioning servo drive.

Product Introduction

When an older positioning machine loses its servo amplifier, replacing the PLC rarely addresses the actual failure. Emerson FX-316 combines position control, feedback processing, servo amplification, and power functions in one motion-control unit.

The drive supports 1 ms motion-path planning and a reported 500 µs position update rate, making it suitable for applications requiring repeatable coordinated positioning. For a legacy servo drive replacement, the motor, feedback device, application modules, and stored motion indexes all need to be checked.

Key Technical Specifications

The 4A current, 1 ms motion planning, 500 µs update rate, 8 inputs, 4 outputs, RS-232C, and 32-index capabilities are reported in secondary technical references describing the FX-316.

Important specification note: Published sources disagree on the exact electrical rating and even provide contradictory voltage/current data for FX-316. One source identifies 960132-01 with the FX-316, while other listings give unsupported 24 VDC or 230 VAC figures. For procurement, the actual nameplate and complete drive configuration should take precedence over generic catalog specifications.

Related Products

• FX-316CE — Related FX Series servo-drive variant. The CE designation indicates a different certification/configuration version; verify motor and electrical compatibility before substitution.
• FX-312 — Related FX Series positioning drive. Lower-capacity configurations may be suitable for smaller motor applications, but output requirements must be matched.
• FX-320 — Related FX Series drive configuration for applications requiring different motor/output capacity. It should not be selected solely by physical similarity.
• DX Series Servo Motors — Brushless motors designed to operate with the FX positioning-drive architecture. Motor winding, resolver feedback, and amplifier rating must match.
• IOM-1 — FX application module providing additional I/O capability. It expands the drive’s interface functions rather than replacing the FX-316 amplifier.
• PCM-1 — Application module used with the FX family for additional programmable motion/interface functions. It is an accessory rather than a substitute for the drive.
• PCM-2 — Related FX application module supporting additional control functions and interfaces.
• PCM-4 — Application module in the FX family that can provide additional interface functionality depending on the machine configuration.
• PCX / PCXWin — Programming/configuration software environment used for setting up FX drive motion indexes and parameters.

FX-316

Frequently Asked Questions

What is Emerson FX-316 used for?

The FX-316 is a positioning servo drive designed for closed-loop motion applications. It combines position control, servo amplification, feedback processing, I/O, and power functions in one unit.

Typical applications include:

• Machine-axis positioning
• Automated assembly equipment
• Material handling
• Packaging machinery
• Indexing mechanisms
• Other brushless-servo applications

Is FX-316 a PLC module?

No.

The FX-316 is fundamentally a servo drive, not a PLC CPU or general-purpose I/O module. It can receive commands from a PLC and provides programmable motion functions internally, including indexed moves, Jog, Home, and Stop operations.

That distinction is important when selecting a replacement.

What motors can Emerson FX-316 drive?

The FX Series was designed around brushless servo motors, with Emerson DX motors specifically identified in available references.

Before connecting a replacement, verify:

1. Motor model.
2. Motor winding/rated current.
3. Feedback/resolver configuration.
4. Brake requirements.
5. Drive current rating.
6. Application-module configuration.
7. Existing motion parameters.

A mechanically compatible motor is not necessarily electrically compatible.

Can I hot-swap the FX-316?

No—do not assume hot-swapping is supported.

This is a servo amplifier connected to motor power and feedback circuitry. Removing or inserting the unit while energized can expose personnel and equipment to electrical and mechanical hazards.

Follow the machine’s lockout/isolation procedure and allow the drive DC bus and associated power circuits to discharge before servicing.

Will I lose my motion program when replacing FX-316?

Normally, the drive’s programmed parameters and indexes are stored in non-volatile memory. Available documentation states that the FX can store up to 32 programmable indexes.

The important point is that the replacement drive may not contain the same program.

Before removing the existing unit, save or document:

• Motion indexes
• Position parameters
• Velocity settings
• Acceleration/deceleration settings
• I/O assignments
• Feedback configuration
• Motor parameters
• Serial communication settings

If the original drive can still communicate with PCX/PCXWin, backing up its configuration should be treated as part of the replacement procedure.

Does FX-316 support firmware v3.1?

The exact firmware revision cannot be confirmed from the FX-316 model number alone.

The FX platform has software/configuration dependencies, and the available technical references identify PCX/PCXWin as the programming environment.

For an existing machine, verify the firmware/software revision on the installed drive and compare it with the replacement before commissioning. Do not assume that two FX-316 units with matching model numbers have identical internal revisions.

How should I verify a New Surplus Emerson FX-316?

For an obsolete servo drive, a cosmetic inspection is not enough.

I would request:

• Exact FX-316 nameplate photograph
• Complete part number, including any suffix
• Serial number
• PCB revision
• Power-section inspection
• Capacitor condition
• Fan/cooling inspection where applicable
• Resolver/feedback interface test
• Digital I/O test
• Servo output test
• Communication test
• Fault/alarm verification
• Controlled motor test
• Test report with measured results

One particularly important point: FX-316 is frequently described incorrectly online as a generic I/O module. More specific references identify it as an Emerson FX Series brushless positioning servo drive. When purchasing replacement stock, match the complete nameplate and drive configuration, not just the words “FX-316.”