Beckhoff Drive Technology
Designing your Application
with AL2000
Last change: 08.11.2001
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Contents
Designing your Application with AL2000
1. Introduction 5
2. System considerations 6
Power Supply 6
Protective Earth 7
Heat dissipation 8
Mounting frame: solidity and stability 9
Positioning 10
Measurement unit 11
3
Servo-controller 12
Accuracy 13
Braking 14
Contamination 15
Cables 16
Bearings 17
Vertical applications 18
Coupling of Coil Units 19
3. Linear motor dimensioning 20
Introduction 20
Physical background 21
Used symbols 22
Used formulas 23
The case 25
Dimensioning force and speed 26
Step 1: Worst case cycle 26
Step 2: Kinematic analysis 28
Step 3: Force analysis 29
Step 4: Motor sizing 30
Step 5: Amplifier sizing 31
4. Appendix 32
Heat transfer and temperature 32
Influences of accuracy 34
5. Technical data 35
List of specifications AL series 35
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Peak force - velocity diagrams 36
DC link diagram 38
Technical data of some optical linear rulers 39
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1. Introduction
With the series AL2000 Beckhoff Industrie Elektronik introduced a wide, standard range of high quality linear
motors. Due to a far-reaching standardization it is possible for designers to select the linear motors themselves.
However specialized knowledge is required for making the right design decisions. This knowledge is provided
here step by step departing form a practical case.
A linear motor of Beckhoff Industrie Elektronik is not a system in itsself. Usually a linear motor is build within a
total machine concept or a working unit. Depending on the application choices have to be made concerning the
specifications and the sizing of the motorsystem. To assure a faultless operation all the components of the motorsystem must comply to strict requirements. In this document the relevant choices and requirements are discussed step by step.
Several stages can be distinguished in a motor system analysis and design proces. In this leaflet you will be
guided through these stages. First of all some system considerations have to be made. These considerations
will provide you with relevant practical information, for instance about the powersupply, heat dissipation, stability, accuracy and braking. As a designer of linear motor systems one should be familiar with some theoretical
physical laws and formulas. This information will be provided together with the step by step analysis and design
proces. Special attention is given to mechanics.
This leaflet is the second of a series of three, concerning Beckhoff Industrie Elektronik AL2000 series Linear
Motors. The series consists of the following titles:
1. A Primer of Linear Motors
2. Designing your Application with AL2000 series Linear Motors
3. Installing AL2000 series Linear Motors
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2. System considerations
Power Supply
The performance of a linear motor is depending on the powersupply. Therefore a linear motor is specified for an
appropriate voltage. The motor’s servo-amplifier can be connected to different voltage power supplies: 230 to
480V, one- or three phase. By means of capacitors and a rectifier bridge the power is transformed in a DC voltage link. For high forces and velocities a DC link is required of at least 560 V. For limited forces and velocities a
310 V DC link will do. For more information about the DC voltage link and the powersupply - motorforce relatio,
please see the appendix - ’Peak force - velocity diagrams’ and - ’DC Link diagram’
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Protective Earth (PE)
To prevent hazardous situations in case of an electrical failure, all metal components must be earthed. The
coilunit housing and ironcore are earthened by the PE of the motor’s power cable. The cable shield is connected to the housing but is not appropriate as PE. Earthen the cable shield on the servo-amplifier to prevent
EMC problems. Follow instructions of the servo-amplifier.
The magnet plates which are bolted to the frame, have to be electrically connected to the frame through the
bolts. The stainless cover of the magnetplate is earthened through the magnetplates. The earthing has to be
checked according to demands with respect to electrical machine safety.
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Heat dissipation
Heat dissipation is a very important but difficult item. Every linear motor produces heat. The heat will mainly be
dissipated in the coil unit. There are two aspects to consider:
1. This heat must flow away to ambient. If possible, the route of the heat conduction should be traced.
2. Heat generation causes temperature differences. That can be unacceptable for accuracy or other reasons.
For your system, especially for the coil unit, the allowed temperature increase should be determined.
The coil unit is fitted with a temperature sensor. In some designs the coil unit is not capable enough of transferring the heat to the surrounding air. This counts especially for heavy loaded motors with a high ratio between
motorforce and coil unit size. Also when the motor is thermally isolated or when ventilation is prevented by a
hood. In these cases active cooling, like water cooling, is needed.
Without cooling an unacceptable heat up of the coil unit could occur. This could result in lower performance,
thermic safety stops and even damage to your motor system. Water-cooling of the motor is very effective to
reduce the heatflow and to obtain a constant temperature of the body. Water-cooling requires a water conditioning unit containing at least a pump and a cooler. Beware of leaking. The temperature sensor can be used to
detect failures of a watercooling system. An additional flow-sensor for controlling the cooling is strictly not necessary, but yields extra safety and system information. If heat up of particular parts of the system is critical, a
thermal insulation between the coil unit and the critical parts of the slide can be considered. This can reduce,
but not nullify, the temperature rise. Sometimes small heat up also takes place in the magnet plates.
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Mounting frame: solidity and stability
The propelling forces of a linear motor are relatively high. Therefore the frame needs sufficient dynamic stiffness. Because of the required accuracy the frame should be insensible to shocks and vibrations.
A linear motor system gaines its accuracy by means of a high bandwidth feedback control loop. In this loop all
mechanical parts such as load, frame and mountings are involved as well as the characteristics of the servocontroller and the linear encoder. The loop can be compromised by the characteristics of the construction. A
bad construction can even cause total loss of control of the linear motor system.
Attention should be paid to the machine’s natural frequencies. Especially vibrations between 50 - 500 Hz in
driving direction can be harmful for accuracy. To meet main problems a rule of thumb is: the motorsystem
should be rigidly connected to a massive and rigid body of at least 3 times the mass of the accelerated load.
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Positioning
LM applications require a sophisticated position and velocity feedback. A linear encoder and a servocontroller
are taken up in the positioning system. The position of the slide is detected by a measurement unit, a rulerprobe combination. The unit’s linear encoder returns the information to the servocontroller. The accuracy of the
motor system depends strongly on this positioning system.
Most measurement units return incremental position information. So the linear motor has to do without the
absolute position of the slide. Especially when starting a motor operation this could be problematical. Herefore
the slide is activated to some minimal testmovement. This ‘magnetic alignment’ supplies the positioning system
with the required information.
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Measurement unit
The series AL2000 motors use a wireless linear encoder for communication, speed and position control. The
performance of the linear motor depends on the characteristics of the applied linear encoder. The use of an
encoder system with a wire is not possible due to the bad dynamic characteristics. The unit is to be connected
and shielded with care. Any disturbance of the positioning signal could lead to positioning failures and system
oscillations.
Several types of measurement units can be applied, such as encoder kits by Heidenhain, Renishaw, Siko and
Numerik Jena. Mostly the resolution should lie between 0.1 and 5 µm. The accuracy of the measurement unit
must at least be better than the required accuracy of the motor system. Depending on the dynamics of the application it can be a factor 2 to 10.
The position of a moving body is measured with respect to the frame. Depending on its stiffness the frame acts
more or less as a reaction force body. In the measurement appearing rotations or vibrations should be disgarded. Therefore the mounting of the measurement unit is critical. The probe should be mounted as close as
possible to the mass centre of the complete moving unit (slide + load), whereas the ruler needs to be placed
near the centroid of the frame. The presence of rotations or vibrations is surmountable but their measurement
and feed back should be avoided.
In exceptional cases stick or slip effects are present. If so the measurement can be placed best between the
bodies between that cause these effects.
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Servo-controller
The position information as well as the current in the coils is fed back to a servocontroller. Here the information
is processed and translated into a proper inputsignal for the linear motor. Because the linear motor needs a
powerful input the signal is provided by a servo-amplifier.
The slide’s movement is directed by a three phase voltage pulse to the coil unit. The phase depends on the
actual and the desired position of the slide. Hereby the motion’s directing quantity is the pulse width. In fact the
servo-amplifier is a pulse width modulation amplifier with a fixed voltage and a fixed switching frequency.
AL2000 linear motors can ideally be combined with our servo-controller series AX2000. With prepared motor-,
feedback- and thermal protection cables we offer a complete and flexible linear motor system.
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Accuracy
Generally the accuracy of the motor system is influenced by
• the accuracy of the error detection and positioning system,
• the static stiffness of the system,
• the dynamic stiffnes of the system
The main restriction for the accuracy arises from the lack of stability of the mounting frame, as discussed be-
fore. Here we discuss the restrictions of the linear motor system.
The linear motor itsself is an electromagnetic device. It deals with resistance and selfinductance. This implies
that the current in the coils always lags behind the provided voltage signal. Since the magnetic force is directly
linked to the current this means that the motorforce also lags behind.
With a static load (constant velocity) the positioning error will be small. Static disturbance arises from cogging at
stand-still or friction. Only a constant force has to be compensated. The system must react with an appropriate
contant force to the disturbance. Generally this is done by an integrator action of the position controller. This
action takes some settling time. The more accurate the positioning, the higher the settling time. An accurate
positioning typically requires a settling time of 5 to 25 ms.
With a dynamic load (accelerating or decelerating) the system shouldn’t just react appropriately but also rapidly.
Now the disturbance is dynamic. It arises from cogging during move, acceleration forces, vabrations and contact forces (for instance when milling). Depending on the stiffness of the whole system the accurcy can deteriorate because of this. As a motor system can be considered as a kind of mass-spring system, it is obvious that
the accuracy is worsened most by disturbances at the system’s natural frequency.
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By the servo controller the returned information of the position, the velocity and the current is processed and
translated into an appropriate voltage signal to the linear motor. The controller has to deal with some delay
because of processor and update times. For a schematic overview, see the appendix ’Influences on accuracy’.
The voltage signal to the linear motor is provided as pulses with a fixed switching frequency. Here the pulse
width is the parameter to be regulated. Accuracy is limited by the fixed pulse frequency and the fixed pulse
voltage.
Needless to say that the accuracy of the positioning system also depends on the accuracy of the linear encoder
and the thermal stability of the system’s components.
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Braking
A controlled stop by the servocontroller is recommended, especially with short runouts. The Servocontroller
stops the motor as quick as possible using the maximum force of the motor. This action has to be activated by a
signal from the position controlling system. Herefore power up is required. In addition there should be no error
status in the servocontroller.
Usually a linear motor’s braking depends on the power supply and position information. Without additive measurements this could result in an uncontrolled rollout to the end of the track in case of power loss or measurement and controlling errors. All active solutions need to be activated by the loss of power or control. This means
that a normal, free motion of the slide is only made possible by one or more unlocked or unbolted braking systems. Suitable is the use of relais.
Risky situations by uncontrolled roll out can be prevented in several ways, such as
1. The use of pneumatic rail guide brakes. This establishes a short runout. Some rail guide suppliers offer brakes that are released by air pressure. These can be very useful for vertical applications and for some safety
situations.
2. Short-circuiting of the motor coils. This results in a moderate runout. A braking force is generated when the
coils are short circuited. There are standard relais for this action. The braking energy is dissipated in the coil
unit. Requirements for relay: current similar to Ipeak, contact resistance below 0.5 Ohms, switching time
according to application requirements.
3. The use of mechanical end stops. Mechanical end stops check the slide at the end of the track. So there is a
maximum run out. Non-flexible end stops are not suitable. Hydraulic or pneumatic dampers absorb the energy
of the movement and stop the slide. Springs cause the slide to be returned, but can be combined with damping
by short circuiting. Requirements: no damage/danger by uncontrolled movement possible
4. a combination of the mentioned measurements.
Which methods are useful depends on the application. For design, consider at least the following worst case
situations:
• Safety violation detected by sensors (linear motor must stop immediatly).
• Programming error, (uncontrolled movement at maximum speed).
• Overtemperature in motor, (linear notor must stop within seconds).
• Fatal error in the Servocontroller (uncontrolled movement).
• Main Power loss (loss of motor control and force).
• DC control Power loss (loss of motor control and force).
• Failure of end of track detector, (hitting end of track).
• Air pressure loss.
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Contamination
As a standard Beckhoff Industrie Elektronik offers a stainless steel cover that can be placed over the magnet
plates. Objects falling on the cover might get jammed causing damage to the system. Particularly small metal
parts such as bolts residing on the cover can be quite harmful.
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Cables
Linear motors have moving cables. In case of watercooling the coolant lines move as well. Take care of mechanical support of the cables and lines. Make moving parts replacable.
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Bearings
To assure a free movement the slide should be provided with robust bearings that run smoothly on two rails.
The rails are mounted aside the magnetplate. This construction ensures the right airgap between the coil unit
and the magnet plate. For the sideward positioning of the coil unit to the magnetplates a small tolerance is acceptable.
The coil unit contains iron parts which are strongly attracted by the permanent magnets of the magnet plate
whether or not the motor is electrically propelled. This attraction force should continuously be beared by the
linear bearings. Therefore it is important to take the attraction force into account when dimensioning the bearings.
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Vertical applications
Linear motors in vertical applications often require a counterbalance mechanism to prevent dropping the load in
the event of power interuption. The counterbalance neutralizes the gravitational force, making an additional
continous force of the linear motor superfluous. The inertia of the motorsystem though could increase. For
counterbalance mechanisms can be thought of springs, pneumatic cylinders or counterweights.
When the moving mass is small, especially when the gravitational force is significantly smaller then the continuous attraction force, the application could do without a counterbalance mechanism.
Coupling of Coil Units
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A magnettrack can be shared by more than one slide. A servocontroller can be shared as well. The following
combinations can be distinguished (see figure).
1. Two (or more) coil units share a magnettrack, each of them directed by it’s own amplifier.
2. Two coil units are coupled (rigidly connected), sharing one amplifier and one magnettrack.
3. Two coil units are coupled, sharing one amplifier. They are running on different parallel tracks.
When two linear motors share one amplifier, they are connected in parallel. For motor sizing objectives the
currents of both motors should be added up. It is not possible to mount motors in series. Use one of the temperature sensors. Use the sensor of the coil unit which is expected to have the worst cooling and also to reach
the highest temperature.
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3. Linear motor dimensioning
Introduction
The choice for the right linear motor size depends on the requirements of your positioning application, especially the worst case requirements. These requirements can be modelled and translated in some characteristic
parameters, such as time, maximum speed, mass of load, inertia and friction. By means of a kinematic and
force analysis these parameters can be linked to typical motor parameters, like peak force and continuous
force. On base of the calculated values an appropriate motor size is to be selected. In addition the appropriate
servo-amplifier can be chosen.
Below a case is worked out as a kind of finger exercise. Understanding this case requires basic knowledge of
some physical laws and principles, especially kinematics and dynamics.
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Physical background
Usually a linear motor’s motion can be distinguished in 3 stages:
1. acceleration
2. constant (or maximum) velocity
3. deceleration
Below this is reperesented in a velocity-time diagram.
Velocity-time diagram for a combined or ' long motion'
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During ta the accelaration takes place and during tc the velocity is constant at its maximum. The decelaration to
stand still takes place in td. The total distance covered by the motion equals the area under the graphical drawing.
During acceleration and decelaration the largest forces are displayed while the movement at constant speed
only requires the force needed to overcome friction. A linear motor that is constantly moving to and fro without
reaching its maximum velocity is thus loaded upmost. In the diagram below this situation is sketched.
Velocity-time diagram for a combined or ' short motion'
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Used symbols
symbol unit description
t s time
t
time needed for acceleration, deceleration or both
a, td tad
tc time needed to cover a distance at constant speed
Dt small time difference
T total time
v m/s velocity
va velocity after acceleration from stand still
v
maximum velocity
max
a m/s² acceleration
x m distance
xa, xd, xc distance covered by acceleration, deceleration or constant speed
X total distance of a combined movement (ta+ tc+ td)
F N force
Fa, Fd, Fad force needed for acceleration and/or deceleration
Fl force applied by the load (like processing contact forces)
F
motor´s peak force
peak
F
motor´s continuous force
cont
Ff friction force
F
mean force over a longer period (root mean square)
rms
M kg mass of the load
Q W dissipated power
S25 N²/W motor constant (slope) at 25°C
STW motor constant at working temperature
K N/A motor force constant
K
mean motor force constant (depending on the current)
rms
I A current
I
motor´s peak current
peak
I
motor´s continuous current
cont
Rth °C/W thermal resistance
TW °C working temperature
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Used formulas
Kinematics
From these formulas two practical estimations can be derived.
1. Estimated time of a ‘short motion’ when vmax is not reached (see ’Velocity-time diagram for a ‘short motion’’):
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2. Estimated time of a ‘long motion’ when vmax is reached (see ’Velocity-time diagram for a combined or ‘long
motion’’):
Dynamics
3. Once you know the mass of the load and having chosen a linear motor type, an estimation of the acceleration can be made by
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Other Formulas
The dissipated power by the linear motor:
The mean motor force constant:
Estimated maximum needed current:
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The case
A gripper places components and moves to and fro continuously: X = 0.8 m. The duration of a single movement
of 0.8 m can ultimately be 0.4 s. On both sides of the movement 0.5 s is needed for settling and gripper action.
Other parameters are:
• The mass of the load: M = 20 kg.
• Friction: Ff = 30 N.
• Slide air cooled, large cooling surface.
• Accuracy approximately 0.02 mm.
• Maximum speed: v
= 3 m/s
max
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Dimensioning force and speed
Step 1: Worst case cycle
Look for the severest job-cycle your application meets. Worst cases happen generally in two situations. First
when the motor produces a high holding force and second where the motor is accelerating and deceleration
continuously (short moves) with little standstill time. Now determine the quantities during the severest job-cycle.
In the case there is only one job-cycle. First let’s choose the type AL2006 motor.
• Calculate the acceleration of this motor:
Note: The value of F
is can be found on the AL2000 series specification sheet.
peak
• The formula to calculate the required time to cover the distance depends on whether the linear motor reaches
its maximum velocity vmax during the movement.
- In the case of a short move (vmax not reached):
- In this case the velocity after ta is:
This calculated velocity va exceeds the maximum velocity required for this application (v
= 3 m/s). It is obvi-
max
ous that the chosen linear motor reaches the maximum velocity somewhere during the motion. In this case we
will have to calculate the required time using the formula for long moves.
Notice that this calculated time exceeds the required travelling time for this application (0,4 s). Therefore a more
heavy type motor like the AL2012 needs to be selected.
So let’s choose the type AL2012 and repeat the calculations.
• Acceleration:
• Required time using the formula for short moves (v
not reached):
max
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• Maximum velocity during acceleration:
Once again this velocity exceeds v
moves (v
reached):
max
therefore the actual velocity is to be calculated using the formula for long
max
This time is in accordance with the requirements. So the AL2012 seems to be the right choice
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Step 2: Kinematic analysis
Sketch a velocity-time diagram for the worst case cycle of your application. Mark the acceleration and deceleration time and the maximum speed. Take 20-40ms extra settlingtime when exact positioning is required.
Case kinematic analysis:
Accelaration and deceleration time and distance:
In this case for acceleration and decelaration the same time and distance are needed. The time needed to
cover the distance of the constant movement (tc = 0,167 s) follows directly from the total time t
calculated
acd
before.
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Step 3: Force analysis
Sketch a motorforce-time diagram. The motorforce depends on:
• Required accelation and deceleration forces.
• Friction forces.
• Processing contact forces (for instance when using bits or cutters).
• For vertical applications: the gravitational forces
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The maximum force F
this. Consider the square time average force F
is the overall maximum force, driving or braking. The motor’s peak force should meet
max
. This force should remain below the motor’s continuous force.
rms
Case force analysis: motorforce versus time diagram:
In the case we get the following results.
Parameter
Acceleration
phase (ta)
Maximum velocity
phase (tc)
Deceleration phase
(td)
Settling and gripper action
phase
Dt(s) 0,1 0,167 0,1 0,5
a(m/s²) 30 0 -30 0
F
(N) 600 0 -600 0
a,c,d
Ff(N) 30 30 30 0
F
(N) 630 30 -570 0
tot
The mean force during the cycle:
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Step 4: Motor sizing
Two main criteria for the motor’s thrust force should be kept in mind:
1. A linear motor’s peak force is depending on the velocity of the coil unit. This can be seen in the linear motor
Specification Diagrams.
Peak force versus velocity (velocity and force in the same direction)
As shown in the diagram this effect depends on the power supply. The speed at F=0 is the limit. For more diagrams see the appendix - ’Peak force - velocity diagrams’.
2. F
must remain below the motor’s specified continous force Fcont. The continuous force is a measure for
rms
the thermal load of the linear motor. Amongst others it depends on the cooling conditions. For watercooling,
Fcont is specified. Without cooling, F
is to be estimated. For more information, see the appendix ’Heat trans-
cont
fer and Temperature’.
Choose a linear motor which meets both criteria.
From the calculated mean force and the specified motorconstant the dissipated power is obtained.
This power equals the heat production in the coil unit. It has to be conducted to ambient.
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Step 5: Amplifier sizing
For most servocontrollers the duration of the peakcurrent is limited from 0.25 to several seconds. If the current
exceeds the continous current during a period, longer than this specified time, the required continous current
must be raised to this higher level. So check whether in long periods the required current is over the continuous
current. Choose a servocontroller which can deliver the required I
Here, from the specified K
and the calculated F
rms
we obtain
rms
The maximum force during the cycle is 630N, so the servo-amplifier has to generate a maximum current
Since the periods of I>I
are no longer than 5 seconds the AX2006 is fullfilling the requirements.
cont
For braking heavy loads from high speeds (for example 100 kg at 4 m/s) the motor feeds back the electrical
power into the servo-amplifier. Most of it is dissipated in a braking resistor. Of course this resistor should be of
sufficient power, especially when such situations occur frequently (for instance in short repeated moves).
cont
and I
peak
.
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4. Appendix
Heat transfer and temperature
The dissipated power in the coil unit causes a heatflow to the ambient. The resulting temperature rise of the
coils is determined by the thermal resistance of the heat conducting route. The coil unit is fitted with a temperature sensor of the PTC 1kOhm type. This sensor detects overtemperature of the coil unit. The servocontroller
should check overtemperature at a level of 1000 Ohms
The water-cooling unit can be connected serial as well as parallel. Parallel connection demands a good flow
through the T-connection pieces. The watercooling lines are linked to the coil unit by means of standard M5
connections. Haake or Julabo cooling system are compliant with Beckhoff Industrie Elektronik linear motors.
Please contact Beckhoff Industrie Elektronik for more information.
As noticed before the linear motor’s continuous force is a measure for the thermal load. Fcont depends on the
motor constant STW and is limited by the allowed working temperature. For watercooling, Fcont is specified. In
that case the thermal resistance of both motor and water can be determined. The heat flow results in a limited
rise of the temperature. T
Heatflow and watercooling
can be kept controlled beneath the allowed working temperature.
coils
The motor constant depends on the temperature.
This means that the motor’s continuous force decreases at high temperatures. When no water cooling is applied, the heat flow usually results in a significant rise of the temperature. The amount depends on the situation.
Sometimes it is not so easy to keep T
controlled beneath the allowed working temperature.
coils
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Heatflow, without water cooling
Now the heat conducting route and the thermal resistance are much harder to determine. The continuous force
has to be estimated. The lower value is specified in the follwing case:
• A mounting surface about two times the motor dimension.
• Air temperature up to 45°C under a closed hood.
• Stationary or short moves.
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The high value can be taken for a large surface (f.i. cooling ribs), forced convection and regulated air temperature below 30°C. For all other situations, estimate a value in between.
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Influences on accuracy
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5. Technical data
List of specifications AL2000 series
Specifications Coils/Current Symbol Unit AL2003 AL2006 AL2012 AL2015 AL2024 AL2030
Motortype
Peak force 3
minutes 1
Peak current
Continuous
Force watercooled
Continuous
Force aircooled 1
Continuous
Power loss
Maximum
speed 2
Motor force
constant
Motor constant
Magnet Pitch
NN
Resistance
per phase
Induction per
phase
Electrical time
constant
Thermal Resistance
Motor Attraction Force
Weight of Coil
unit
Temperature
Sensor
1
Depends on application: cooling surface, air speed and ambient temperature
2
Depends on available voltage and required force
3-phase synchronuos
magnet@25°C Fp N 200 400 800 1000 1600 2000
Ip Arms 5 5 10 10 20 20
@100°C Fcw N 105 210 420 525 840 1050
@100°C Fca N 50...
100
all coils Pc W 80 155 310 370 620 740
Vmax m/s 6.0 6.0 6.0 6.0 6.0 6.0
< 0.6Ip K N/Arms 46 93 93 112 93 112
@25°C S N²/W 185 370 740 970 1480 1940
t mm 24 24 24 24 24 24
@25°C Rf O 3.9 7.8 3.9 4.3 1.9 2.2
<0.6Ip Lf mH 30 60 30 35 15 17.5
@25°C τe ms 8 8 8 8 8 8
Rth °C/W 0.96 0.48 0.24 0.20 0.12 0.10
Fa N 500 900 1700 2000 3400 4000
Mc kg 0.9 1.5 2.6 3.2 5.1 6.3
PTC 1 kO
100...
200
200...
400
250...
500
400..
800
500..
1000
35
36
Eiserstraße 5 / D-33415 Verl / Telefon 05246/963-0 / Telefax 05246/963-149
Peak force - velocity diagrams
Velocity diagram AL2003
Velocity diagram AL2006
Velocity diagram AL2012
Eiserstraße 5 / D-33415 Verl / Telefon 05246/963-0 / Telefax 05246/963-149
37
Velocity diagram AL2015
38
Eiserstraße 5 / D-33415 Verl / Telefon 05246/963-0 / Telefax 05246/963-149
DC link diagram
P1, P2 and P3: the three phases of the AC power supply.
• D1 ... D6: these diodes are part of the 3 phase diode bridge.
• C: the DC link capacitor.
• Tb: the activating transistor of the braking resistor.
• Rb: the braking resistor.
• T1 ... T6: transistors of the PWM amplifier stage.
• L1, L2 and L3: The coils of the motor.
Eiserstraße 5 / D-33415 Verl / Telefon 05246/963-0 / Telefax 05246/963-149
Technical data of some optical linear rulers
39
Manufacturer
type
Heidenhain
LIP481
Heidenhain
LIF181 (C)
Heidenhain
LIDA181 (C)
Heidenhain
LIDA185(C)
Heidenhain
LS485
Heidenhain
LS486(C)
Litton/Zeiss
LIE5-1PC-FA
Renishaw
RGH-2XR
Encoder
period Stability Repaetability Accuracy
2µm <2nm <10nm ± 0.1, 0.2, 0.5 or
1µm/m
4µm <10nm <25nm ± 3 or 5µm/m 1m/s 1Vpp
40µm <80nm <200nm ± 5µm/m 8m/s 1Vpp
40µm <80nm <200nm ± 3 or 5µm/m 8m/s 1Vpp
20µm <40nm <100nm ± 5µm/m 8 m/s 1Vpp
20µm <100nm <500nm ± 3 or 5µm/m 1 m/s
20µm <50nm <100nm ± 5µm/m 8m/s
20µm <50nm <100nm ± 3µm/m 4m/s 1Vpp
Maximum
speed Interface
5m/s
TTL
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