Lorenz DR-1986 User manual

LORENZ MESSTECHNIK GmbH
Obere Schloßstr.131
73553 Alfdorf
07172 / 93730-0
Fax [phone]
E-Mail: [e-mail]
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090327.docx
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Page 1 of 12
Operation Manual
for Torque Sensors
For below and similar Types
DR-1986
DR-1987
DR-1988
DR-2124

LORENZ MESSTECHNIK GmbH
Obere Schloßstr.131
73553 Alfdorf
07172 / 93730-0
Fax [phone]
E-Mail: [e-mail]
Technical changes reserved
090327.docx
Internet: www.lorenz-sensors.com
Page 2 of 12
Imprint
Manufacturer, Place
Lorenz Messtechnik GmbH, D-73553 Alfdorf.
Valid for...
DR-1986; DR-1987; DR-1988; DR-2124
Copyright
© 2012 Lorenz Messtechnik GmbH, Alfdorf.
Reprint Interdiction
Reprints, even in extracts, only with written authority.
Modification
Technical changes reserved.
References in this Text
1.6 Warning Notes; Page 4
Attention must be paid to the accident prevention regulations of the trade associations.
Coverings and casings are necessary before operating the sensor. This is also valid for
commissioning, maintenance and trouble shooting.
Duties of the coverings and casings are:
Protection from detaching parts
Protection from contusion and shear
Prevention from reaching rotating parts
Prevention from being tangled up and/or getting caught by parts
Coverings may
Not grind
Not rotate
Coverings are also necessary outside of operating and motion travel areas of persons.
These demands can be modified if other sufficient safety devices are available. During operation,
the safety precautions must be operative. By vibrations, damages can occur at the device.
4 Mechanical Assembly; Page 7
It must be ensured that no materials (e.g. liquids, gases) from other components of the spindle get
into the torque sensor.
Before the assembly, spline drive (or square drive) must be cleaned with dissolver (e.g. acetone)
and lightly greased, no foreign particles may adhere to them. The hub must fit corresponding to the
connection.
Caution: During the assembly inadmissibly large forces may not act on the sensor or the mechanical
connections. At small torques (< 50 N·m) connect the sensor electrically during the assembly and
observe the signal, the measurement signal may not exceed the limit values.
6 Measuring; Page 9
Warming-up period of the torque sensor is approx. 5 min.
6.4.1 Natural Resonances; Page 10
An operation of the device in natural resonance can lead to permanent damages.

LORENZ MESSTECHNIK GmbH
Obere Schloßstr.131
73553 Alfdorf
07172 / 93730-0
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Contents
1Read First.............................................................................................................................................. 4
1.1 Safety and Caution Symbols.......................................................................................................... 4
1.2 Intended Use.................................................................................................................................. 4
1.3 Dangers.......................................................................................................................................... 4
1.3.1 Neglecting of Safety Notes ..................................................................................................... 4
1.3.2 Remaining Dangers ................................................................................................................ 4
1.4 Reconstructions and Modifications ................................................................................................ 4
1.5 Personnel ....................................................................................................................................... 4
1.6 Warning Notes ............................................................................................................................... 4
2Term Definitions .................................................................................................................................... 5
2.1 Terms ............................................................................................................................................. 5
3Product Description ............................................................................................................................... 5
3.1 Mechanical Setup........................................................................................................................... 5
3.2 Electrical Setup .............................................................................................................................. 6
3.2.1 Sensors with Analog Output ................................................................................................... 6
4Mechanical Assembly............................................................................................................................ 7
5Electrical Connection............................................................................................................................. 8
5.1 Pin Connection............................................................................................................................... 8
5.1.1 Standard Version .................................................................................................................... 8
5.2 Calibration Control ......................................................................................................................... 8
5.2.1 Calibration Control at Analog Output ...................................................................................... 8
5.3 Cable.............................................................................................................................................. 8
5.4 Shielding Connection ..................................................................................................................... 9
5.5 Running of Measuring Cables........................................................................................................ 9
5.6Angle (Option) ................................................................................................................................ 9
6Measuring.............................................................................................................................................. 9
6.1 Engaging ........................................................................................................................................ 9
6.2 Direction of Torque......................................................................................................................... 9
6.3 Static / Quasi-Static Torques ......................................................................................................... 9
6.4 Dynamic Torques ........................................................................................................................... 9
6.4.1 Natural Resonances ............................................................................................................. 10
6.5 Speed Limits ................................................................................................................................ 10
6.6 Disturbance Variables .................................................................................................................. 10
7Maintenance........................................................................................................................................ 10
7.1 Maintenance Schedule ................................................................................................................ 10
7.2 Trouble Shooting.......................................................................................................................... 11
8Decommission..................................................................................................................................... 11
9Transportation and Storage ................................................................................................................ 11
9.1 Transportation .............................................................................................................................. 11
9.2 Storage......................................................................................................................................... 11
10 Disposal ........................................................................................................................................... 12
11 Calibration........................................................................................................................................ 12
11.1 Proprietary Calibration.............................................................................................................. 12
11.2 DKD-Calibration........................................................................................................................ 12
11.3 Re-Calibration........................................................................................................................... 12
12 Data Sheet....................................................................................................................................... 12
13 Literature.......................................................................................................................................... 12

LORENZ MESSTECHNIK GmbH
Obere Schloßstr.131
73553 Alfdorf
07172 / 93730-0
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E-Mail: [e-mail]
Technical changes reserved
090327.docx
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1 Read First
1.1 Safety and Caution Symbols
Caution:
Injury Risk for Persons
Damage of the Device is possible.
Note:
Important points to be considered.
1.2 Intended Use
Torque sensors are intended for the measurement of torques. This measurand is further suitable for
control tasks. The valid safety regulations should be absolutely respected. The torque sensors are not
safety components in the sense of the intended use. The sensors need to be transported and stored
appropriately. The assembly, commissioning and disassembling must take place professionally.
1.3 Dangers
The torque sensor is fail-safe and corresponds to the state of technology.
1.3.1 Neglecting of Safety Notes
At inappropriate use, remaining dangers can emerge (e.g. by untrained personnel). The operation manual
must be read and understood by each person entrusted with the assembly, maintenance, repair,
operation and disassembly of the torque sensor.
1.3.2 Remaining Dangers
The plant designer, the supplier, as well as the operator must plan, realize and take responsibility for
safety-related interests for the sensor. Remaining dangers must be minimized. Remaining dangers of the
torque measurement technique must be pointed out.
Human mistakes must be considered. The construction of the plant must be suitable for the avoidance of
dangers. A danger-analysis for the plant must be carried out.
1.4 Reconstructions and Modifications
Each modification of the sensors without our written approval excludes liability on our part.
1.5 Personnel
The installation, assembly, commissioning, operation and the disassembly must be carried out by
qualified personnel only. The personnel must have the knowledge and make use of the legal regulations
and safety instructions.
1.6 Warning Notes
Attention must be paid to the accident prevention regulations of the trade associations.
Coverings and casings are necessary before operating the sensor. This is also valid for
commissioning, maintenance and trouble shooting.
Duties of the coverings and casings are:
Protection from detaching parts
Protection from contusion and shear
Prevention from reaching rotating parts
Prevention from being tangled up and/or getting caught by parts
Coverings may
Not grind
Not rotate
Coverings are also necessary outside of operating and motion travel areas of persons.
These demands can be modified if other sufficient safety devices are available. During
operation, the safety precautions must be operative. By vibrations, damages can occur
at the device.

LORENZ MESSTECHNIK GmbH
Obere Schloßstr.131
73553 Alfdorf
07172 / 93730-0
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2 Term Definitions
2.1 Terms
Measuring Side:
Mechanical connection of the torque sensor in which the torque to be measured is applied. Usually this
side has the smallest moment of inertia.
Drive Side:
Mechanical connection of the torque sensor on the opposite side of the measuring side, usually with the
largest moment of inertia. At static torque sensors the housing is fastened on this side.
3 Product Description
The sensor measures following static and dynamic measurements:
Torque
Speed
Angle
The installation position of the torque sensor can be chosen freely.
Caution: it is to be differentiated between measuring side and drive side, see data sheet of the sensor:
http://www.lorenz-sensors.com
3.1 Mechanical Setup
The sensors consist of a torsion shaft. Depending on design, the mechanical connection possibilities are
executable with spline drive or square drive etc. The torsion shaft, applied with two strain gauge full
bridges, is bedded in a housing through ball bearings. For the signal transmission and/or the supply of the
strain gauge full bridges, a rotating transformer, according to the principle of a transformer, is arranged in
the sensor. For supply and measuring signal conditioning, electronics are integrated in the stator and the
rotor.
Schematical Drawing of the Mechanical Setup
SG
Rotating transformer
Shaft
Measuring side
Drive side
Electronics in the stator
Angle Sensor
Electronics in the rotor

LORENZ MESSTECHNIK GmbH
Obere Schloßstr.131
73553 Alfdorf
07172 / 93730-0
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3.2 Electrical Setup
The supply of the rotor electronics occurs by an alternating voltage, generated in the stator, which
transfers to the rotor through a rotating transformer. There, it is rectified and stabilized. With this supply,
the strain gauge bridge is fed.
For the electrical calibration control of the sensor, a control signal is up-modulated to the supply by the µ-
processor in the stator and transferred to the rotor. There, it is filtered and evaluated by the µPC, which
also activates the internal switch for the detuning of the strain gauge bridge.
The measuring signal of the strain gauge bridge is conditioned in an amplifier and then converted into a
digital signal, which will be transferred to the stator by another rotating transformer. Compared to the
analog signal, the measuring signal in digital form is much more disturbance-free. The remaining distance
of the measuring signal within the sensor occurs in digital form, completely. Thus, the measuring system
achieves a high reliability of operation.
This signal is further conditioned in the stator, comes into a µ-processor, then - depending upon sensor
type - it is converted to a voltage signal, digital signal or to current and will then reach the output of the
sensor and can be directly measured at the connector.
DC
/
DC
Oscillator
4
MHz
Signal
Conditioning
Signal Adaption
Analog or Digital
Signal
Conditioning
A/D-Converter
12
bit
µ
-
Processor
µ
-
Processor
Rotation Angle (Option)
SG
Supply
Voltage
Calibration
Control
Signal
Output
Rotation
Angle Output
(
Option
)
Amplifier
Stator
Rotor
Rotating Transformer
Serial Data Transmission
A
B
AC
DC
Filter for
Control Signal
Cycle and
Control Signal
Supply and
Control Signal
Rotating Transformer
Block Diagram for Serial Signal Transmission
3.2.1 Sensors with Analog Output
At this output, the digital signal is converted into DC voltage of ±5 V (option ±10 V), proportionally to the
torque and is available at the connector output.

LORENZ MESSTECHNIK GmbH
Obere Schloßstr.131
73553 Alfdorf
07172 / 93730-0
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4 Mechanical Assembly
Installation Instructions:
It must be ensured that no materials (e.g. liquids, gases) from other components of the
spindle get into the torque sensor.
Before the assembly, spline drive (or square drive) must be cleaned with dissolver (e.g.
acetone) and lightly greased, no foreign particles may adhere to them. The hub must fit
corresponding to the connection.
Caution: During the assembly inadmissibly large forces may not act on the sensor or the
mechanical connections. At small torques (< 50 N·m) connect the sensor electrically
during the assembly and observe the signal, the measurement signal may not exceed the
limit values.
Type DR-1986
The shaft of the torque sensor is designed with an inner and external square connector. The shaft is used
to transmit torque to the screwdriver.
The mechanical connection to the spindle housing occurs via a screw connection.
Type DR-1987 and DR-1988
The shaft of the torque sensor is designed with an inner and external square connector. The shaft is used
to transmit torque to the screwdriver.
The mechanical connection to the spindle housing occurs via a tooth system and a union nut.
Type DR-2124
The shaft of the torque sensor is designed with a splined shaft and tooth hub connection. The shaft is
used to transmit torque to the screwdriver.
The mechanical connection to the spindle housing occurs via a tooth system and a union nut.

LORENZ MESSTECHNIK GmbH
Obere Schloßstr.131
73553 Alfdorf
07172 / 93730-0
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Page 8 of 12
E
Excitation GND
K
Calibration control
5 Electrical Connection
5.1 Pin Connection
The torque sensors are equipped with a 12-pin connector (Binder miniature circular connectors series
680, 12-pin)
5.1.1 Standard Version
Also see data sheet
12-pin
A
NC
B
Angle B
TTL
C
Signal
±5 V / (±10 V)
D
Signal GND
0 V
E
Excitation GND
0 V
F
Excitation +
12 ... 28 VDC
G
Angle A
TTL
H
NC
J
NC
K
Calibration control
L<2,0 V; H>3,5 V
L
NC
M
Housing
5.2 Calibration Control
Only use calibration control in unloaded condition of the torque sensor.
5.2.1 Calibration Control at Analog Output
By applying voltage of +5 V to +28 V the calibration control will
switch on.
Voltage below 2,8 V will switch off the calibration control.
5.3 Cable
Only use a shielded cable with preferably small capacity. We recommend measuring cables from our
product range. They have been tested in combination with our sensors and meet the metrological
requirements.
+
Ukal
Exc. GND
Cal. control
3,5 VDC < Ukal < 28 VDC
View: Socket on Soldering Side

LORENZ MESSTECHNIK GmbH
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73553 Alfdorf
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5.4 Shielding Connection
In combination with the sensor and the external electronics, the shield forms a Faraday Cage. By this,
electro-magnetic disturbances do not have any influence on the measurement signal.
5.5 Running of Measuring Cables
Do not run measuring cables together with control or heavy-current cables. Always assure that a large
distance is kept to engines, transformers and contactors, because their stray fields can lead to
interferences of the measuring signals.
If troubles occur through the measuring cable, we recommend to run the cable in a grounded steel
conduit.
5.6 Angle (Option)
At angle or speed measurement, the pulses / revolutions
are acquired. By a second transmitter trace, displaced by
90° and flank evaluation, the pulses / revolutions can be
quadrupled. The trace, displaced by 90°, can also be
used for the rotational direction detection.
See corresponding data sheet for the output levels.
Supply for angle sensor
Stabilized supply voltage
5 V ±25 mV
Current consumption max.
20 mA
6 Measuring
6.1 Engaging
The warming-up period of the torque sensor is approx. 5 min. Afterwards the measurement can be
started.
The warming-up period of the torque sensor is approx. 5 min.
6.2 Direction of Torque
Torque means clockwise or clockwise torque if the torque acts clockwise when facing the shaft end. In
this case a positive electrical signal is obtained at the output.
Torque sensors by Lorenz Messtechnik GmbH can measure both, clockwise and counter-clockwise
direction.
6.3 Static / Quasi-Static Torques
Static and/or quasi-static torque is a slowly changing torque.
The calibration of the sensors occurs statically on a calibration device.
The applied torque may accept any value up to the nominal torque.
6.4 Dynamic Torques
The static calibration procedure of torque sensors is also valid for dynamic applications.
Note: The frequency of torques must be smaller than the natural frequency of the mechanical
measurement setup.
The band width of alternating torque must be limited to 70 % of the nominal torque.

LORENZ MESSTECHNIK GmbH
Obere Schloßstr.131
73553 Alfdorf
07172 / 93730-0
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Page 10 of 12
6.4.1 Natural Resonances
Estimate of the mechanical natural frequencies:










21
0
11
2
1
JJ
cf

f0
J1, J2
c
= Natural Frequency in Hz
= Moment of Inertia in kg*m²
= Torsional Rigidity in Nm/rad
Further methods for the calculation of natural resonances are corresponding purchasable programs or
books (e.g. Holzer-Procedure, Dubbel, Taschenbuch für den Maschinenbau, Springer Verlag)
An operation of the device in natural resonance can lead to permanent damages.
6.5 Speed Limits
The maximum speed indicated in the data sheet may not be exceeded in any operating state..
6.6 Disturbance Variables
By disturbances, measured value falsifications can occur by
Vibrations,
Temperature gradients,
Temperature changes,
Arising disturbance variables during operation, e.g. imbalance,
Electrical disturbances,
Magnetic disturbances,
EMC (electromagnetic disturbances),
Therefore avoid these disturbance variables by decoupling of vibrations, covers, etc.
7 Maintenance
7.1 Maintenance Schedule
Action
Frequency
Date
Date
Date
Control of cables and connectors
1x p.a.
Calibration
< 26 months
Control of fixation (flanges, shafts)
1x p.a.
Have bearings exchanged by Lorenz
Messtechnik GmbH
20000 hrs
operating time
c
J1
J2

LORENZ MESSTECHNIK GmbH
Obere Schloßstr.131
73553 Alfdorf
07172 / 93730-0
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Page 11 of 12
7.2 Trouble Shooting
This chart should help to search for the most frequent errors and their elimination
Problem
Possible Cause
Trouble Shooting
No signal
No sensor excitation
Outside of permissible range
Connect excitation
Cable defect
No mains supply
Signal output connected wrong
Connect output correctly
Evaluation electronics defect
Sensor does not react to torque
Shaft not clamped
Clamp correctly
No power supply
Outside of permissible range
Connect supply
Cable defect
No mains supply
Cable defect
Repair cable
Connector connected wrong
Connect correctly
Signal has dropouts
Axial position rotor to stator
outside of tolerance
Align rotor
Cable defect
Repair cable
Zero point outside of tolerance
Cable defect
Repair cable
Shaft mounted distorted
Mount correctly
Distorted shaft string
Release from distortion
Strong lateral forces
Reduce lateral forces
Distorted flanges
Check evenness of flange-
surfaces
Shaft overloaded
Send to manufacturer
Wrong torque indication
Calibration not correct
Re-calibrate
Sensor defect
Repair by manufacturer
Torque shunt
Eliminate shunt
Oscillations
Alignment of shaft not correct
Align correctly
Unbalance
Balance the corresponding
parts
8 Decommission
All sensors must be dismantled professionally. Do not strike sensor housings with tools. Do not apply
bending moments on the sensor, e.g. through levers. The torque sensor must be supported to avoid
falling down during the dismantling.
9 Transportation and Storage
The transportation of the sensors must occur in suitable packing.
For smaller sensors, stable cartons which are well padded are sufficient (e.g., air cushion film, epoxy
crisps, paper shavings). The sensor should be tidily packed into film so that no packing material can
reach into the sensor (ball bearings).
Larger sensors should be packed in cases.
9.1 Transportation
Only release well packed sensors for transportation. The sensor should not be able to move back and
forth in the packing. The sensors must be protected from moisture.
Only use suitable means of transportation.
9.2 Storage
The storage of the sensors must occur in dry, dust-free rooms, only.
Slightly lubricate shafts and flanges with oil before storing (rust).

LORENZ MESSTECHNIK GmbH
Obere Schloßstr.131
73553 Alfdorf
07172 / 93730-0
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Page 12 of 12
10 Disposal
The torque sensors must be disposed according to the valid provisions of law.
For this, see our “General Terms and Conditions” www.lorenz-sensors.com
11 Calibration
At the time of delivery, torque sensors have been adjusted and tested with traceable calibrated measuring
equipment at factory side. Optionally, a calibration of the sensors can be carried out.
11.1 Proprietary Calibration
Acquisition of measurement points and issuance of a calibration protocol. Traceable calibrated measuring
equipment is being used for the calibration. The sensor data are being checked during this calibration.
11.2 DKD-Calibration
The calibration of the sensor is carried out according to the guidelines of the DKD. The surveillance of the
calibrating-laboratory takes place by the DKD. At this calibration, the uncertainty of measurement of the
torque measuring instrument is determined. Further information can be obtained from Lorenz
Messtechnik GmbH.
11.3 Re-Calibration
The recalibration of the torque sensor should be carried out after 26 months at the latest.
Shorter intervals are appropriate:
Overload of the sensor
After repair
After inappropriate handling
Demand of high-quality standards
Special traceability requirements
12 Data Sheet
See www.lorenz-sensors.com
13 Literature
Dubbel, Taschenbuch für den Maschinenbau, Springer Verlag