TRINAMIC QSH2818-51-07 User guide

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QMot QSH2818 family

Manual

V1.04

2010-OCT-19

Trinamic Motion Control GmbH & Co. KG

Sternstraße 67

D – 20357 Hamburg, Germany

http://www.trinamic.com

QSH2818 Manual (V1.04 / 2010-OCT-19) 2

Table of contents

1 Life support policy ....................................................................................................................................................... 3

2 Features........................................................................................................................................................................... 4

3 Order codes .................................................................................................................................................................... 5

4 Mechanical dimensions .............................................................................................................................................. 6

4.1 Lead wire configuration .................................................................................................................................... 6

4.2 Dimensions ........................................................................................................................................................... 6

5 Torque figures ............................................................................................................................................................... 7

5.1 Motor QSH2818-32-07-006 ................................................................................................................................. 7

5.2 Motor QSH2818-51-07-012 ................................................................................................................................. 7

6 Considerations for operation.................................................................................................................................... 8

6.1 Choosing the best fitting motor for an application ................................................................................. 8

6.1.1 Determining the maximum torque required .................................................................................... 8

6.2 Motor current setting ......................................................................................................................................... 9

6.2.1 Choosing the optimum current setting ............................................................................................. 9

6.2.2 Choosing the standby current .............................................................................................................. 9

6.3 Motor driver supply voltage .......................................................................................................................... 10

6.3.1 Determining if the given driver voltage is sufficient .................................................................. 10

6.4 Back EMF (BEMF) ................................................................................................................................................ 11

6.5 Choosing the commutation scheme ........................................................................................................... 11

6.5.1 Fullstepping ............................................................................................................................................. 12

6.5.1.1 Avoiding motor resonance in fullstep operation ............................................................. 12

6.6 Optimum motor settings ................................................................................................................................ 12

6.6.1 Settings for the TRINAMIC TMCL™ modules.................................................................................. 12

7 Revision history .......................................................................................................................................................... 13

7.1 Documentation revision .................................................................................................................................. 13

8 References .................................................................................................................................................................... 14

List of figures

Figure 4.1: Lead wire configuration ................................................................................................................................ 6

Figure 4.2: Dimensions (all values in mm) ................................................................................................................... 6

Figure 5.1: QSH2818-32-07-006 speed vs. torque characteristics ............................................................................. 7

Figure 5.2: QSH2818-51-07-012 speed vs. torque characteristics ............................................................................. 7

List of tables

Table 2.1: Motor technical data ......................................................................................................................................... 4

Table 4.1: Lead wire configuration .................................................................................................................................. 6

Table 6.1: Motor current settings ..................................................................................................................................... 9

Table 6.2: Driver supply voltage considerations ........................................................................................................ 10

Table 6.3: Comparing microstepping and fullstepping ............................................................................................ 11

Table 6.4: Optimum motor settings .............................................................................................................................. 12

Table 5.5: Optimum motor settings for TMCL™ modules (tested with TMCM-110) ........................................ 12

Table 6.1: Documentation revision ................................................................................................................................ 13

QSH2818 Manual (V1.04 / 2010-OCT-19) 3

1 Life support policy

TRINAMIC Motion Control GmbH & Co. KG does not authorize or warrant any of its products for use in life support systems, without the specific written consent of TRINAMIC Motion Control GmbH & Co. KG.

Life support systems are equipment intended to support or sustain life, and whose failure to perform, when properly used in accordance with instructions provided, can be reasonably expected to result in personal injury or death.

Information given in this data sheet is believed to be accurate and reliable. However neither responsibility is assumed for the consequences of its use nor for any infringement of patents or other rights of third parties, which may result from its use.

Specifications are subject to change without notice.

QSH2818 Manual (V1.04 / 2010-OCT-19) 4

Specifications

Parameter

Units

QSH2818

-32-07-006

-51-07-012

Rated Voltage

RATED

V 3.8

6.2

Rated Phase Current

RMS_RATED

A 0.67

0.67

Phase Resistance at 20°C

COIL

Ω 5.6

9.2

Phase Inductance (typ.)

3.4

7.2

Holding Torque (typ.) Ncm 6 12

oz in

8.5

17.0

Detent Torque

Ncm

Rotor Inertia

g cm2 9 18

Weight (Mass)

0.11

0.2

Insulation Class

B B

Insulation Resistance

Ω 100M

100M

Dialectic Strength (for one minute)

VAC

500

Connection Wires

N° 4 4

Max applicable Voltage

V tbd

tbd

Step Angle

° 1.8

1.8

Step angle Accuracy (max.)

% 5 5

Flange Size (max.)

28.0

Motor Length (max.)

MAX

Axis Diameter

5.0

Axis Length (typ.)

20.0

Shaft Radial Play (450g load)

0.02

Shaft Axial Play (450g load)

0.08

Maximum Radial Force (20 mm from front flange)

Maximum Axial Force

N 10

Ambient Temperature

°C

-20…+50

Temp Rise (rated current, 2phase on)

°C

max. 80

Related Trinamic PANdrive

type

PD1-108-28

PD3-108-28

2 Features

These two phase hybrid stepper motors are optimized for microstepping and give a good fit to the TRINAMIC family of motor controllers and drivers.

Main characteristics:

 NEMA 11 mounting configuration  flange max. 28.0mm * 28.0mm  5mm axis diameter, 20mm axis length  step angle: 1.8˚  optimized for microstep operation  optimum fit for TMC222 / TMC236 / TMC246 / TMC262 based driver circuits  4 wire connection  CE approved

Table 2.1: Motor technical data

QSH2818 Manual (V1.04 / 2010-OCT-19) 5

Order code

Description

Dimensions (mm)

QSH2818-32-07-006

QMot stepper motor 28mm, 0.67A, 6 Ncm

28 x 28 x 32

QSH2818-51-07-012

QMot stepper motor 28mm, 0.67A, 12 Ncm

28 x 28 x 51

3 Order codes

Table 3.1: Order codes

QSH2818 Manual (V1.04 / 2010-OCT-19) 6

black

green

red

blue

Length

22-0/0.03

20±1

15±2

4.5

0.5

Ø5-0/0.012

5±0.2

3+0/0.1

QSH2818

-32-07-006

-51-07-012

Length

28 max

23±0.2

4 x M2.5 Deep 3.5

Cable type

Gauge

Coil

Function

Black

UL1007 AWG26

Motor coil A pin 1

Green

UL1007 AWG26

A-

Motor coil A pin 2

Red

UL1007 AWG26

Motor coil B pin 1

Blue

UL1007 AWG26

B-

Motor coil B pin 2

Table 4.1: Lead wire configuration

4 Mechanical dimensions

4.1 Lead wire configuration

Figure 4.1: Lead wire configuration

4.2 Dimensions

Figure 4.2: Dimensions (all values in mm)

QSH2818 Manual (V1.04 / 2010-OCT-19) 7

5 Torque figures

The torque figures detail motor torque characteristics for half and full step. For half and full step operation there are always a number of resonance points (with less torque) which are not depicted. These will be minimized by microstep operation in most applications.

5.1 Motor QSH2818-32-07-006

Testing conditions: VM: 24V 0.67A /Phase Driver, SMD 103

Figure 5.1: QSH2818-32-07-006 speed vs. torque characteristics

5.2 Motor QSH2818-51-07-012

Testing conditions: VM: 24V 0.67A /Phase Driver, SMD 103

Figure 5.2: QSH2818-51-07-012 speed vs. torque characteristics

QSH2818 Manual (V1.04 / 2010-OCT-19) 8

6 Considerations for operation

The following chapters try to help you to correctly set the key operation parameters in order to get a stable system.

6.1 Choosing the best fitting motor for an application

For an optimum solution it is important to fit the motor to the application and to choose the best mode of operation. The key parameters are desired motor torque and velocity. While the motor holding torque describes the torque at stand-still, and gives a good indication for comparing different motors, it is not the key parameter for the best fitting motor. The required torque is a result of static load on the motor, dynamic loads which occur during acceleration/deceleration and loads due to friction. In most applications the load at maximum desired motor velocity is most critical, because of the reduction of motor torque at higher velocity. While the required velocity generally is well known, the required torque often is only roughly known. Generally, longer motors and motors with a larger diameter deliver a higher torque. But, using the same driver voltage for the motor, the larger motor earlier looses torque when increasing motor velocity. This means, that for a high torque at a high motor velocity, the smaller motor might be the better fitting solution.

Please refer to the torque vs. velocity diagram to determine the best fitting motor, which delivers enough torque at your desired velocities.

6.1.1 Determining the maximum torque required

Try a motor which should roughly fit. Take into consideration worst case conditions, i.e. minimum driver supply voltage and minimum driver current, maximum or minimum environment temperature (whichever is worse) and maximum friction of mechanics. Now, consider that you want to be on the safe side, and add some 10 percent safety margin taking into account unknown degradation of mechanics and motor.

QSH2818 Manual (V1.04 / 2010-OCT-19) 9

Percentage of

rated current

Percentage of

motor torque

Percentage of static

motor power dissipation

Comment

150%

≤150%

225%

Limit operation to a few seconds

125%

156%

Operation possible for a limited time

100%

= 2 * I

RMS_RATED

* R

COIL

Normal operation

85%

72%

Normal operation

75%

56%

Normal operation

50%

25%

Reduced microstep exactness due to torque reducing in the magnitude of detent torque

38%

14%

-“-

25%

-“-

see detent

torque

Motor might lose position if the application’s friction is too low

6.2 Motor current setting

Basically, the motor torque is proportional to the motor current, as long as the current stays at a reasonable level. At the same time, the power consumption of the motor (and driver) is proportional to the square of the motor current. Optimally, the motor should be chosen to bring the required performance at the rated motor current. For a short time, the motor current may be raised above this level in order to get increased torque, but care has to be taken in order not to exceed the maximum coil temperature of 130°C respectively a continuous motor operation temperature of 90°C.

Table 6.1: Motor current settings

6.2.1 Choosing the optimum current setting

Generally, you choose the motor in order to give the desired performance at nominal current. For short time operation, you might want to increase the motor current to get a higher torque than specified for the motor. In a hot environment, you might want to work with a reduced motor current in order to reduce motor self heating.

The TRINAMIC drivers allow setting the motor current for up to three conditions:

- Stand still (choose a low current)

- Nominal operation (nominal current)

- High acceleration (if increased torque is required: You may choose a current above the nominal

setting, but be aware, that the mean power dissipation shall not exceed the motors nominal rating)

If you reach the velocity limit, it might be a good idea to reduce the motor current, in order to avoid resonances occurring. Please refer to the information about choosing the driver voltage.

6.2.2 Choosing the standby current

Most applications do not need much torque during motor stand-still. You should always reduce motor current during stand still. This reduces power dissipation and heat generation. Depending on your application, you typically at least can half power dissipation. There are several aspects why this is possible: In standstill, motor torque is higher than at any other velocity. Thus, you do not need the full current even with a static load! Your application might need no torque at all, but you might need to keep the exact microstep position. Try how low you can go in your application. If the microstep position exactness does not matter for the time of standstill, you might even reduce the motor current to zero, provided that there is no static load on the motor and enough friction in order to avoid complete position loss.

QSH2818 Manual (V1.04 / 2010-OCT-19) 10

Parameter

Value

Comment

Minimum driver supply voltage

2 * U

COIL_NOM

Very limited motor velocity. Only slow movement without torque reduction. Chopper noise might become audible.

Optimum driver supply voltage

≥ 4 * U

COIL_NOM

and ≤ 22 * U

COIL_NOM

Choose the best fitting voltage in this range using the motor torque curve and the driver data. You can scale the torque curve proportionally to the actual driver supply voltage.

Maximum rated driver supply voltage

25 * U

COIL_NOM

When exceeding this value, the magnetic switching losses in the motor reach a relevant magnitude and the motor might get too hot at nominal current. Thus there is no benefit in further raising the voltage.

COIL_NOM

= I

RMS_RATED

* R

COIL

6.3 Motor driver supply voltage

The driver supply voltage in many applications cannot be chosen freely, because other components have a fixed supply voltage of e.g. 24V DC. If you have possibility to choose the driver supply voltage, please refer to the driver data sheet, and consider that a higher voltage means a higher torque at higher velocity. The motor torque diagrams are measured for a given supply voltage. You typically can scale the velocity axis (steps/sec) proportionally to the supply voltage to adapt the curve, e.g. if the curve is measured for 48V and you consider operation at 24V, half all values on the x-Axis to get an idea of the motor performance.

For a chopper driver, consider the following corner values for the driver supply voltage (motor voltage). The table is based on the nominal motor voltage, which normally just has a theoretical background in order to determine the resistive loss in the motor.

Comment on the nominal motor voltage:

(Please refer to motor technical data table.)

Table 6.2: Driver supply voltage considerations

6.3.1 Determining if the given driver voltage is sufficient

Try to brake the motor and listen to it at different velocities. Does the sound of the motor get raucous or harsh when exceeding some velocity? Then the motor gets into a resonance area. The reason is that the motor back-EMF voltage reaches the supply voltage. Thus, the driver cannot bring the full current into the motor any more. This is typically a sign, that the motor velocity should not be further increased, because resonances and reduced current affect motor torque.

Measure the motor coil current at maximum desired velocity

For microstepping: If the waveform is still basically sinusoidal, the motor driver supply voltage is

sufficient.

For Fullstepping: If the motor current still reaches a constant plateau, the driver voltage is

sufficient.

If you determine, that the voltage is not sufficient, you could either increase the voltage or reduce the current (and thus torque).

QSH2818 Manual (V1.04 / 2010-OCT-19) 11

Driver Scheme

Resolution

Velocity range

Torque

Comments

Fullstepping

200 steps per rotation

Low to very high. Skip resonance areas in low to medium velocity range.

Full torque if dampener used, otherwise reduced torque in resonance area

Audible noise especially at low velocities

Halfstepping

200 steps per rotation * 2

Low to very high. Skip resonance areas in low to medium velocity range.

Full torque if dampener used, otherwise reduced torque in resonance area

Audible noise especially at low velocities

Microstepping

200 * (number of microsteps) per rotation

Low to high.

Reduced torque at very high velocity

Low noise, smooth motor behavior

Mixed: Microstepping and fullstepping for high velocities

200 * (number of microsteps) per rotation

Low to very high.

Full torque

At high velocities, there is no audible difference for fullstepping

 

NmngTorqueMotorHoldi

srad

NOM

BEMF





 



 



6.4 Back EMF (BEMF)

Within SI units, the numeric value of the BEMF constant has the same numeric value as the numeric value of the torque constant. For example, a motor with a torque constant of 1 Nm/A would have a BEMF constant of 1V/rad/s. Turning such a motor with 1 rps (1 rps = 1 revolution per second =

6.28 rad/s) generates a BEMF voltage of 6.28V.

The Back EMF constant can be calculated as:

The voltage is valid as RMS voltage per coil, thus the nominal current I formula, since the nominal current assumes a full step position, with two coils switched on. The torque is in unit [Nm] where 1Nm = 100cNm = 1000mNm.

One can easily measure the BEMF constant of a two phase stepper motor with a (digital) scope. One just has to measure the voltage of one coil (one phase) when turning the axis of the motor manually. With this, one gets a voltage (amplitude) and a frequency of a periodic voltage signal (sine wave). The full step frequency is 4 times the frequency the measured sine wave.

is multiplied by 2 in this

NOM

6.5 Choosing the commutation scheme

While the motor performance curves are depicted for fullstepping and halfstepping, most modern drivers provide a microstepping scheme. Microstepping uses a discrete sine and a cosine wave to drive both coils of the motor, and gives a very smooth motor behavior as well as an increased position resolution. The amplitude of the waves is 1.41 times the nominal motor current, while the RMS values equal the nominal motor current. The stepper motor does not make loud steps any more – it turns smoothly! Therefore, 16 microsteps or more are recommended for a smooth operation and the avoidance of resonances. To operate the motor at fullstepping, some considerations should be taken into account.

Table 6.3: Comparing microstepping and fullstepping

QSH2818 Manual (V1.04 / 2010-OCT-19) 12

Optimum Motor Settings

Unit

QSH2818

-32-07-006

-51-07-012

Motor current (RMS)

0.67

Motor voltage

Maximum microstep velocity = Fullstep threshold

RPS

5.817

4.578

Maximum fullstep velocity

RPS

12.875

9.155

Optimum Motor Settings

Unit

QSH2818

-32-07-006

-51-07-012

Motor current (RMS)

TMCL™ value

947

Motor voltage

Maximum microstep velocity = Fullstep threshold

TMCL™ value

610

480

Maximum fullstep velocity

TMCL™ value

1350

960

Microstepping gives the best performance for most applications and can be considered as state-of-the art. However, fullstepping allows some ten percent higher motor velocities, when compared to microstepping. A combination of microstepping at low and medium velocities and fullstepping at high velocities gives best performance at all velocities and is most universal. Most Trinamic driver modules support all three modes.

6.5.1 Fullstepping

When operating the motor in fullstep, resonances may occur. The resonance frequencies depend on the motor load. When the motor gets into a resonance area, it even might not turn anymore! Thus you should avoid resonance frequencies.

6.5.1.1 Avoiding motor resonance in fullstep operation

Do not operate the motor at resonance velocities for extended periods of time. Use a reasonably high acceleration in order to accelerate to a resonance-free velocity. This avoids the build-up of resonances. When resonances occur at very high velocities, try reducing the current setting.

A resonance dampener might be required, if the resonance frequencies cannot be skipped

6.6 Optimum motor settings

The following table shows the settings for the highest reachable fullstep velocities.

Table 6.4: Optimum motor settings

6.6.1 Settings for the TRINAMIC TMCL™ modules

Following TMCL™ settings apply best for highest motor velocities and smooth motor behavior at low velocities. They are intended for the use with TRINIMICs controller modules.

Mixed decay should be switched on constantly. Microstep resolution is 4 (TMCL™), this is 16 times microstepping. The pulse devisor is set to 3. With a 64 microstep setting the same values are valid with the pulse divisor set to 1.

Table 6.5: Optimum motor settings for TMCL™ modules (tested with TMCM-110)

QSH2818 Manual (V1.04 / 2010-OCT-19) 13

Version

Comment

Author

Description

1.00

Initial Release

1.01

2007-JUN-07

Chapter 6.6 optimum motor settings added

1.02

2007-NOV-13

Chapter 6.4 Back EMF (BEMF) added

1.03

2010-AUG-11

New technical drawing of the motor, minor changes

1.04

2010-OCT-19

Minor changes

7 Revision history

7.1 Documentation revision

Table 7.1: Documentation revision

QSH2818 Manual (V1.04 / 2010-OCT-19) 14

[TMCL™]

TMCLTM manual, www.trinamic.com

8 References

TRINAMIC QSH2818-51-07 User guide

Specifications and Main Features

Frequently Asked Questions

User Manual