Neometrix / Electromechanical Actuator Test Systems / Electromechanical Actuator Test System / NMX-EAT-49

NMX-EAT-49 · ENGINEERED-TO-ORDER CLASS — FIT · FREE RUN · LOAD · HOLD · ENDURE · RECORD

Electromechanical Actuator Test System. The load is the test.

Name: Electromechanical Actuator Test System
SKU: NMX-EAT-49

An electromechanical actuator is proved by what it does under load: how hard it pushes, how far it gives, and how hot it gets. None of that shows while it moves freely.

So the system has two jobs. It pushes back with a load machine that behaves like the real load, and it measures force, stroke, speed, current and temperature together, on one clock.

Discuss an actuator test system Capability note (PDF)

A single electromechanical actuator test bench in a test hall: a slim aluminium linear actuator with a dark grey servo motor, a plain stainless load cell in line, and a larger grey hydraulic load cylinder at the far end of a rigid grey reaction bed, with two black hoses and one black cable, and no people

Fig · 01 — An actuator test bench: the actuator under test, an in-line load cell, and a hydraulic load cylinder on a rigid reaction bed — illustrative render.

The load

a machine that pushes backspring, hydraulic or electric

The channels

force, stroke, speedcurrent and temperature

The tests

free, loaded, heldand run until it heats

The record

one clock, one recordper actuator tested

Status

engineered to orderno system yet delivered

ISO 9001ISO 14001ISO 3408 ball screw referenceIEC 60068 environmental test reference

Overview

Why an actuator test is judged by the load that pushes back.

Because an actuator moving freely proves almost nothing. Force, heat and wear all appear only when something resists.

Fig · 02 — The system in one picture: the actuator drives its output, the load machine pushes back, and every channel is measured on one clock.

The load is the test. Without one, nothing is proved.

What the system is for

It tests electromechanical actuators on a bench: how hard they push, how far they move, how fast, how accurately, how long they last, and how they behave when they run hot or must hold.

Why the load is the hard part

A real load is a mix of weight, spring, damping and inertia, and it changes through the stroke. The bench must reproduce that mix with a load machine, because a fixed weight tests only one point of it.

Why free and loaded runs differ

Moving the actuator with no load shows its speed, its friction and its lost motion. Loading it shows its force, its stiffness, its heat and its wear. A bench that does only the first has not tested the actuator.

Why lost motion and stiction are measured

Lost motion is the slack taken up when the direction reverses, and stiction is the extra force needed to start moving. Both decide how well the actuator positions, and both change as it wears, so they are measured and kept.

Why heat is logged all the way through

The motor heats as it works, and the heat decides how long a duty can be kept up. The bench logs temperature and current through the whole run, so a duty that passes early and fails late is caught.

Why holding is tested on its own

Where the actuator must hold a load with no power, the brake or the screw has to do it. The bench applies the load, removes the power and watches for creep, so the holding claim is measured and not assumed.

The method

Fit, free run, load, hold, endure, and record.

Six steps in a fixed order. The two shaded steps are the ones a quick check skips.

FIG · 02ELECTROMECHANICAL ACTUATOR TEST SYSTEM · FIT / FREE RUN / LOAD / HOLD / ENDURE / RECORD — THE LOAD IS THE TEST

The step people underrate is the load. An actuator that has only been moved on the bench has been shown to move, and nothing more.

Fig · 03 — Three things a free run cannot show: lost motion, stiction and creep — a drawing of the idea, with no values.

1 · Fit

The actuator is mounted on a stiff fixture, aligned so that it sees axial load only, and fitted with force, stroke and temperature sensors.

2 · Free run

The actuator is moved with no load, to show its speed, its friction and its lost motion at reversal.

3 · Load

The load machine pushes back along the profile the actuator will really see, while force, stroke and current are logged.

4 · Hold

The load is applied, the power is removed, and the output is watched for creep.

5 · Endure

Long cycles are run with the temperature and the current kept all the way through.

6 · Record

Everything is kept on one clock, one record for each actuator tested.

Work content

What the bench contains, element by element.

Read it as a checklist: a bench missing a row will buy that row back later, usually as a result nobody quite believes.

A single test fixture detail on a grey steel base plate: a plain stainless load cell with a clevis eye at each end, pinned between the polished rod end of a linear actuator and a rigid grey steel fixture block, with one thin black cable, and no people

Fig · 04 — An actuator rod end pinned through a load cell to a rigid fixture block, the load path of the bench — illustrative render.

Element	What it does	What matters
Test fixture	holds the actuator and its load path	stiff and aligned, so that the actuator sees axial load only and the fixture does not give
Load machine	pushes back	passive, hydraulic or electric, chosen from the actuator's force, speed and stroke
Force measurement	measures the push	a load cell in line with the actuator, traceable, with the fixture's own stiffness known
Position & speed	measure stroke and speed	a linear sensor on the output, independent of the actuator's own feedback
Electrical measurement	reads current, voltage and power	on every phase, on the same clock as force and stroke
Temperature	reads motor and housing heat	sensors on the motor, the housing and the screw nut, logged through the whole run
Controller & data acquisition	run the profile and log it	closed-loop control of the load, and one clock for every channel
Environmental chamber	holds the temperature	optional, for hot and cold runs, with the sensors inside it
Safety circuit	protects people and the actuator	guards, force and stroke limits, and a stop that removes the power and the load together
Procedure	fixes the sequence	fit, free run, load, hold, endure and record, the same for every actuator
Testing & documentation	prove the bench first	the bench checked against a reference load cell, and a record the customer can inspect

The element that decides whether a result is believable is not the actuator under test. It is the bench's own stiffness and alignment. A fixture that gives, or that loads the actuator off its axis, makes a good actuator look bad.

Fig · 05 — One bench, three load machines: passive, hydraulic and electric, with the load machine chosen to suit the actuator.

Full specification — expand

Bench	A stiff fixture and reaction frame that loads the actuator axially; a load machine that pushes back, passive, servo-hydraulic or electric; an in-line load cell; a linear sensor on the output that is independent of the actuator's own feedback; current, voltage and power measurement; temperature sensors on the motor, housing and screw nut; closed-loop control of the load; data acquisition on one clock; an optional environmental chamber; a safety circuit; a written procedure; and testing and documentation before handover
The One Idea	An actuator can only be tested against a load, so the load machine is the real instrument.
Why The Load Is The Hard Part	A real load is a mix of weight, spring, damping and inertia that changes through the stroke, so the bench reproduces that mix with a load machine, because a fixed weight tests only one point of it
Why Free And Loaded Runs Differ	Moving the actuator with no load shows its speed, its friction and its lost motion, while loading it shows its force, its stiffness, its heat and its wear, so a bench that does only the first has not tested the actuator
Why Lost Motion And Stiction Are Measured	Lost motion is the slack taken up when the direction reverses and stiction is the extra force needed to start moving; both decide how well the actuator positions, and both change as it wears, so they are measured and kept
Why Heat Is Logged All The Way Through	The motor heats as it works and the heat decides how long a duty can be kept up, so temperature and current are logged through the whole run and a duty that passes early and fails late is caught
Why Holding Is Tested On Its Own	Where the actuator must hold a load with no power, the brake or the screw must do it, so the bench applies the load, removes the power and watches for creep
Standards	ISO 3408 is the public reference for ball screws, including their load ratings and acceptance tests, IEC 60068 is the public reference for environmental testing, and ISO/IEC 17025 is the public reference for the competence of testing laboratories. None of them sets the force, the speed or the life a particular actuator must show: those come from the customer's specification, and this page prints none of it. Accreditation of a laboratory rests with the customer and their assessors; none is claimed here
Configurations	An acceptance bench for short checks against a passive load, a performance bench with a programmable load and every channel, and an endurance bench with a chamber and a temperature log
Scope Boundary	This is the bench that tests electromechanical actuators. It is not the actuator itself (see electromechanical actuator), not a bench for hydraulic actuators (see servo-hydraulic actuator test bench), not a motion platform (see dynamic motion tilt test platform), and not a calibration laboratory: none is claimed here
Status	Neometrix has quoted against successive actuator test system requirements, and no delivered electromechanical actuator test system is claimed.

Configurations

One method, three benches to choose from.

The method, the record and the pass rule are shared. What changes is how much of the bench is built.

Acceptance bench

Fixture, passive load, logger

A bench for short checks of finished actuators against a passive load, with force and stroke logged on one clock.

Performance bench

Fixture, load machine, control

A bench with a programmable load machine that follows a profile, and every channel logged through the run.

Endurance bench

Fixture, chamber, logger

A bench for long cycles in a chamber, with temperature and current kept all the way through.

Fig · 06 — Three benches, one method: an acceptance bench, a performance bench, or an endurance bench.

And the part that is not equipment at all, yet decides all three: the test profile. It fixes the loads, the cycles and the pass rule, and it is written from the duty the actuator will see, not from the bench.

Where it is used

Wherever an actuator has to be shown to push, hold and last.

The common thread is an actuator whose performance has to be proved on a bench, because it cannot be proved on paper.

Production test

Where every finished actuator is run against a known load before it leaves the line, and a record is kept for each one.

Design verification

Where a new actuator is run through its full duty on a performance bench, and the loops are tuned on the real actuator under load.

Qualification and endurance

Where an actuator must run long cycles, hot and cold, with its temperature kept, before it is accepted.

Overhaul and incoming inspection

Where actuators are checked after repair or on receipt, and their lost motion and holding are compared with the last record.

FAQ

Common questions.

Longer answers, for readers who want the reasoning.

Q · 01 How does an electromechanical actuator test bench work?

The actuator is mounted on a stiff fixture, with its output coupled through a load cell to a load machine. The controller drives the actuator along a profile while the load machine pushes back along its own profile, and the bench logs force, stroke, speed, current and temperature on one clock. A free run comes first, then loaded runs, then a hold with the power removed, then long cycles with the temperature kept. The result is one record for the actuator, which can be compared with the next one or with the last.

Q · 02 Why can a hanging weight not test an actuator?

Because a weight gives one force, and a real load gives a mix. A spring load rises with the stroke, a damping load rises with the speed, and a mass load matters when the actuator speeds up or slows down. A weight tests one point of that mix and hides the rest. A load machine, whether passive, servo-hydraulic or electric, can follow a profile of force against position, speed or time, so the actuator meets a load that behaves like the real one. That is why the load machine, not the actuator, is the instrument that decides what the bench can show.

Q · 03 What are lost motion and stiction, and why measure them?

Lost motion is the slack in the drive: when the direction reverses, the output does not move until the slack is taken up. Stiction is the extra force needed to get the output moving from rest. Both decide how well the actuator can position, and neither shows on a free run at speed. Both change as the screw and the nut wear, so a measurement kept from the first test is the best warning that the actuator is ageing. The bench measures them with a linear sensor on the output that is independent of the actuator's own feedback.

Q · 04 Is this the same as the electromechanical actuator, servo-hydraulic actuator test bench or servo-hydraulic fatigue testing machine pages?

No, and the differences are worth stating precisely. The electromechanical actuator page is the actuator itself, sized from its duty, and this page is the bench that tests one. The servo-hydraulic actuator test bench page is a bench for fluid-power actuators, with its own hydraulic supply and schedules. The servo-hydraulic fatigue testing machine page is a general-purpose load frame for specimens and structures, not a bench built around one actuator with its own current and temperature channels. This page does not replace any of them, and it does not claim what they claim a second time.

Q · 05 What can the system not do?

It tests one actuator at a time, on a bench, and a bench cycle is a model of the duty, not the duty itself: the profile is only as true as the duty it was written from. It cannot make a poor fixture believable, which is why the bench's own stiffness and alignment are checked against a reference load cell before any actuator is trusted to it. It does not set the force, the speed or the life an actuator must show, and no force, stroke, speed or life figure is printed here. No laboratory accreditation is claimed: this page claims none. Acceptance of an actuator rests with the customer and the authority they name; none is claimed here.

Q · 06 Has Neometrix built one of these?

We would rather answer this plainly than let a page imply otherwise. Neometrix has quoted against successive actuator test system requirements, and no delivered electromechanical actuator test system is claimed. What stands behind the offer is adjacent: Neometrix engineers electromechanical actuators (see the electromechanical actuator page) and servo-hydraulic test benches that load and measure actuators (see the servo-hydraulic actuator test bench and servo-hydraulic fatigue testing machine pages). The load cells, linear sensors and data-acquisition hardware are catalogue items, bought in, not invented. What Neometrix engineers is the bench around them: the fixture and reaction frame, the load machine and its control, the safety circuit, the profiles, the procedure and the records. So the honest position is that the system is engineered to order, the neighbouring disciplines are in the building, and the first bench of this exact kind will be built around the customer's own actuator and duty rather than lifted off a shelf.

Q · 07 Which standards apply, and who sets the pass rule?

ISO 3408 is the public reference for ball screws, including their load ratings and acceptance tests, IEC 60068 is the public reference for environmental testing, and ISO/IEC 17025 is the public reference for the competence of testing laboratories. None of them sets the force, the speed or the life a particular actuator must show: those come from the customer's specification, and this page prints none of it. Acceptance of the finished bench, including its proving runs before handover, rests with the customer and whatever authority they name.

Q · 08 What do you need from us to quote?

Six things, and most of them describe your actuator rather than the bench. First, the actuator: its type, size and mounting, and how many a year are to be tested. Second, the load: the forces, the stroke and the way the real load behaves, whether spring, weight, damping or a mix. Third, the tests: free run, loaded runs, hold and endurance, and which of them each actuator must pass. Fourth, the environment: whether a chamber is needed, and over what range. Fifth, the record: the channels, the pass rule and the format you want kept. Sixth, the site: the floor, the power and the safety rules. From that we come back with a bench concept, a written test method you can check, and a budgetary price.

The neighbouring pages, and how they differ from this one.

Three neighbours: the actuator itself, a bench for fluid-power actuators, and a general-purpose load frame.

↗ The actuator itself

Electromechanical Actuator

The actuator that this bench tests - sized from its duty, not from its peak.

↗ A bench for fluid-power actuators

Servo-Hydraulic Actuator Test Bench

A bench for hydraulic actuators, with its own supply - not for electric ones.

↗ A general-purpose load frame

Servo-Hydraulic Fatigue Testing Machine

A load frame for specimens and structures - not a bench built around one actuator.

Browse all Neometrix product lines.

Get a quotation

Tell us the actuator, the load,
and the record.

The projects desk replies within two working days with a bench concept, a written test method you can check, and a budgetary quotation. Write to [email protected] or use the form.

Enquire — actuator test system Capability sheet (PDF) +91 7777 876 876

ISO 9001 / 14001 ENGINEERED-TO-ORDER CLASS — ELECTROMECHANICAL ACTUATOR TEST SYSTEM FIT · FREE RUN · LOAD · HOLD · ENDURE · RECORD — THE LOAD IS THE TEST ENGINEERED IN NOIDA · INDIA