A servo drive, also called a servo amplifier, takes a position, velocity or torque command from a motion controller and delivers precisely regulated current to a servo motor, closing the loop with encoder or resolver feedback thousands of times per second. Lose the drive and you lose the axis, which usually means the whole machine. MT.parts keeps 270+ servo drives and amplifiers in stock from the leading motion control brands, including units that are discontinued or no longer sold by the manufacturer.
Where these drives are used
- CNC machining centers and lathes, driving feed axes and spindle amplifiers on the machine tool.
- Packaging machinery, on rotary knives, flying shears and cam profiles that must stay locked to the line.
- Pick and place, gantries and robotics, where multi-axis drive systems share a common DC bus.
- Printing and web converting, holding registration between unwind, print and rewind sections.
- All-electric injection molding and press automation, replacing hydraulics with torque-controlled axes.
- Electronics and semiconductor assembly, on precision stages where micron-level positioning is routine.
How to choose a replacement servo drive
A servo drive is matched to a motor and a controller, not just to a machine. Check these before ordering:
- Part number first. The exact catalog number on the nameplate is the safest match. Search it in our catalog.
- Continuous and peak output current in amps, together with the motor power rating. Two drives of the same family can differ only in current frame.
- Input voltage and power structure, single-phase 120 or 240 V versus three-phase 400 to 480 V, and whether the axis runs standalone or off a shared DC bus with a separate power supply module.
- Feedback interface, incremental encoder, absolute single-turn or multi-turn encoder, or resolver. The drive must speak the same feedback protocol as the motor already installed.
- Command and network interface, EtherNet/IP with CIP Motion, PROFINET, EtherCAT, SERCOS, or analog and step and direction inputs, so the drive still talks to the existing controller.
- Motor pairing and firmware revision, since many systems refuse to enable an axis when the drive firmware does not match the controller project or the motor catalog number in the configuration.
If you are unsure which code replaces yours, send us the nameplate data and our team identifies the correct unit.
New, refurbished and obsolete servo drives
We supply three conditions, and the condition is always stated on the product page. New units are factory-sealed. Refurbished units are inspected, repaired where needed and functionally tested before shipping. Obsolete and hard-to-find drives are models the manufacturer has discontinued, which is often the only way to keep an older machine running without replacing the motors, the cables and the motion program at the same time. Every drive we ship carries a 12-month warranty.
Servo drive brands and series we stock
- Allen-Bradley: Kinetix 5100, Kinetix 5300, Kinetix 5500, Kinetix 5700, Kinetix 6000 AM and IAM modules, ArmorKinetix DSD
- Mitsubishi Electric: servo amplifiers listed individually by catalog number
- Fanuc: servo and spindle amplifier modules for machine tool systems
- Siemens: servo drive and axis modules listed by order number
- Yaskawa: servo amplifiers listed by model code
- Schneider Electric: servo drives listed by commercial reference
- Omron: servo drives listed by model code
Frequently asked questions
How is a servo drive different from a VFD and from a servo motor?
A variable frequency drive regulates the speed of a standard AC induction motor, usually in open loop, for pumps, fans and conveyors. A servo drive regulates position, velocity and torque of a servo motor in closed loop, with feedback and bandwidth high enough for indexing and synchronized motion. The drive is the electronics in the cabinet; the servo motor is the machine-mounted motor with the feedback device. They are ordered as a matched pair and are not interchangeable.
Can I replace a discontinued servo drive with a newer model?
Sometimes, but a newer drive family often changes the feedback connector, the motor cables, the network protocol and the configuration software, so the motor and the motion program may have to change with it. Replacing with the same discontinued catalog number keeps the axis exactly as commissioned. We stock obsolete drives for that reason.
Do refurbished servo drives come with a warranty?
Yes. New, refurbished and obsolete drives all ship with a 12-month warranty.
How fast can I get a quote?
We reply to quote requests within 24 hours, including part identification when you only have nameplate data.
Do you ship internationally?
Yes. We ship worldwide, including to plants outside the United States.
Can't find your part number?
If the servo drive or amplifier you need is not listed, we source it. Send us the manufacturer, part number and quantity, and our team locates the unit, including discontinued models. Request a quote.
