Magtrol TM 300 Series User manual

TM 300 Series
In-Line Torque Transducers
User’s Manual
Via Paolo Uccello 4 - 20148 Milano
Tel [phone] Fax [phone] [email protected] www.dspmindustria.it

1st English Edition, rev. G– June 2011
While every precaution has been exercised in the compilation of this document to ensure
the accuracy of its contents, Magtrol, Inc./Magtrol SA assumes no responsibility for
errors or omissions. Additionally, no liability is assumed for any damages that may result
from the use of the information contained within this publication.
COPYRIGHT
Copyright ©2006–2008 Magtrol, Inc. All rights reserved.
Copying or reproduction of all or any part of the contents of this manual without the
express permission of Magtrol is strictly prohibited.
TRADEMARKS
LabVIEW™ is a trademark of National Instruments Corporation.
Microsoft® is a registered trademark of Microsoft Corporation.
National Instruments™ is a trademark of National Instruments Corporation.
Windows® is a registered trademark of Microsoft Corporation.
Purchase Record
Please record all model numbers and serial numbers of your
Magtrol equipment, along with the general purchase information.
The model number and serial number can be found on either
a silver identification plate or white label affixed to each unit.
Refer to these numbers whenever you communicate with a
Magtrol representative about this equipment.
Model Number: _____________________________
Serial Number: _____________________________
Purchase Date: _____________________________
Purchased From: _____________________________

i
Safety Precautions
Warning! in order to minimize risks, it is of utmost
importance to respect the current safety
standards When planning, configuring and
operating the torque measurement drive
train.
1. Make sure that all Magtrol electronic products are earth-grounded, to ensure personal safety
and proper operation.
2. Check line voltage before operating electronic equipment.
3. Make sure that all rotating parts are equipped with appropriate safety guards.
Note: Detailed information regarding safety guards can be found in Section
2.5 – Protective Systems.
4. Periodically check all connections and attachments.
5. Always wear protective glasses when working with rotating elements.
6. Never wear a necktie or baggy clothes when standing close to rotating elements.
7. Never stand too close or bend over the rotating drive chain.

ii
The contents of this manual is subject to change without prior notice.
REVISION DATE
First English edition, revision G – June 2011
Revisions to this Manual
Date Edition Change Section(s)
20.06.11 1st Edition - rev. G Accuracy update for TMB 301 to 313 1.3.1, 1.3.2
26.05.11 1st Edition - rev. F Overload limit updated 1.3.1, 1.3.2, 1.3.3
04.10.10 1st Edition - rev. E Added information regarding vertical installation of a TM/TMB 2.1.3
28.07.09 1st Edition - rev. D Added information regarding connection to an differential amplifier 2.7.3
10.09.08 1st Edition - rev. C Updated: Figure 2–3 Parastic Forces 2.2
12.18.07 1st Edition - rev. B New transducer model: TM 309 1.3.2, 2.2.1, 2.2.2
and 2.4.3
01.10.07 1st Edition - rev. A Added information regarding connection to non-Magtrol electronics. 2.7.3

iii
Table of Contents
SAFETY PRECAUTIONS .........................................................................................................................I
REVISIONS TO THIS MANUAL ...............................................................................................................II
REVISION DATE .................................................................................................................................................................II
TABLE OF REVISIONS ......................................................................................................................................................II
TABLE OF CONTENTS ..........................................................................................................................III
TABLE OF FIGURES ........................................................................................................................................................ IV
PREFACE ................................................................................................................................................ V
PURPOSE OF THIS MANUAL ......................................................................................................................................... V
WHO SHOULD USE THIS MANUAL .............................................................................................................................. V
MANUAL ORGANIZATION ............................................................................................................................................. V
1. INTRODUCTION .................................................................................................................................1
1.1 GENERAL INFORMATION ........................................................................................................................................ 1
1.2 DESCRIPTION ............................................................................................................................................................. 1
1.3 DATA SHEETS ............................................................................................................................................................. 2
1.3.1 TM 301 – TM 308 ........................................................................................................................................... 2
1.3.2 TM 309 – TM 313 ........................................................................................................................................... 6
1.3.3 TM 314 – TM 317 ......................................................................................................................................... 12
2. INSTALLATION / CONFIGURATION ................................................................................................17
2.1 MOUNTING POSSIBILITIES ................................................................................................................................... 17
2.1.1 Suspended Installation .................................................................................................................................. 17
2.1.2 Supported Installation ................................................................................................................................... 17
2.1.3 TM/TMB in Vertical Installation ................................................................................................................... 18
2.2 PARASITIC FORCES ................................................................................................................................................. 18
2.2.1 Radial Forces (Bending) ............................................................................................................................... 19
2.2.2 Axial Forces (Thrust) .................................................................................................................................... 20
2.3 MEASURING SHAFT VIBRATIONS ....................................................................................................................... 21
2.3.1 Permitted Vibrations on Measuring Shaft ..................................................................................................... 21
2.3.2 Torque Signal Conditioning Electronic Circuit ............................................................................................. 23
2.4 MOUNTING LIMITS ................................................................................................................................................. 24
2.4.1 Dynamic Torque ............................................................................................................................................ 24
2.4.2 Natural Frequency of Drive Train ................................................................................................................. 24
2.4.3 Natural Measuring Shaft Torsional Frequency ............................................................................................. 26
2.4.4 Maximum Dynamic Amplitude..................................................................................................................... 27
2.5 PROTECTIVE SYSTEMS .......................................................................................................................................... 27
2.6 ELECTRONIC SIGNAL PROCESSING .................................................................................................................... 29
2.6.1 Model 3410 Torque Display .......................................................................................................................... 29
2.6.2 Model 6400 Torque Transducer Display ....................................................................................................... 30
2.6.3 Model DSP6001 Programmable Dynamometer Controller .......................................................................... 31
2.7 ELECTRICAL CONNECTIONS ............................................................................................................................... 32
2.7.1 Grounding ..................................................................................................................................................... 32
2.7.2 Connecting Cable .......................................................................................................................................... 33
2.7.3 Connection to Non-Magtrol Electronics ....................................................................................................... 34
3. OPERATING PRINCIPLES ...............................................................................................................36
3.1 TORQUE TRANSDUCER ARCHITECTURE .......................................................................................................... 36

iv
Table of Contents Magtrol TM Series In-Line Torque Transducers
TABLE OF FIGURES
3.1.1 Differential Transformer ............................................................................................................................... 37
3.2 SPEED CONDITIONING CHAIN ............................................................................................................................. 37
3.3 BUILT-IN SELF-TEST CIRCUIT .............................................................................................................................. 37
4. MAINTENANCE / REPAIR ................................................................................................................38
4.1 MAINTENANCE ........................................................................................................................................................ 38
4.2 REPAIR ....................................................................................................................................................................... 39
SERVICE INFORMATION ......................................................................................................................40
RETURNING MAGTROL EQUIPMENT FOR REPAIR AND/OR CALIBRATION ..................................................... 40
Returning Equipment to Magtrol, Inc. (United States) ............................................................................................... 40
Returning Equipment to Magtrol SA (Switzerland) .................................................................................................... 40
1. INTRODUCTION
Figure 1–1 TMB 313 In-Line Torque Transducer .......................................................................................................1
2. INSTALLATION / CONFIGURATION
Figure 2–1 Suspended Installation ...........................................................................................................................17
Figure 2–2 Supported Installation ............................................................................................................................18
Figure 2–3 Parasitic Forces ......................................................................................................................................18
Figure 2–4 Radial Displacement ..............................................................................................................................21
Figure 2–5 Vibratory Acceleration ............................................................................................................................22
Figure 2–6 SW1 – SW12 Micro-switches and Offset Adjustment Potentiometer ......................................................23
Figure 2–7 Simplified Drive Train Model .................................................................................................................24
Figure 2–8 Frequency Response Graph ....................................................................................................................25
Figure 2–9 Admissible Dynamic Load ......................................................................................................................27
Figure 2–10 Example of Protective System...............................................................................................................28
Figure 2–11 Model 3410 Torque Display .................................................................................................................29
Figure 2–12 PC-Based System Configuration with Model 3410 Display .................................................................29
Figure 2–13 Model 6400 Torque Transducer Display ..............................................................................................30
Figure 2–14 PC-Based System Configuration with Model 6400 Display .................................................................30
Figure 2–15 Model DSP6001 Programmable Dynamometer Controller .................................................................31
Figure 2–16 PC-Based System Configuration with Model DSP6001 Controller .....................................................31
Figure 2–17 Common Grounding .............................................................................................................................32
Figure 2–18 6-pin Souriau Connector Configuration ...............................................................................................33
Figure 2–19 14-pin Centronics Connector Configuration ........................................................................................33
Figure 2–20 Wiring Diagram for Connection to Non-Magtrol Electronics ..............................................................34
Figure 2-21 ER 107 Pin Configuration .....................................................................................................................35
3. OPERATING PRINCIPLES
Figure 3–1 TM Torque Transducer Principal Elements ............................................................................................36

v
Preface
PURPOSE OF THIS MANUAL
This manual contains information required for the installation and general use of Magtrol’s TM
Series In-Line Torque Transducers. To achieve maximum capability and ensure proper use, please
read this manual in its entirety before operating the unit. Keep the manual in a safe place for quick
reference whenever a question should arise.
WHO SHOULD USE THIS MANUAL
This is written for operators installing a torque transducer as part of a test system that meausres the
torque on transmission chains. The operator is assumed to have the necessary technical training in
electronics and mechanical engineering enabling him to install the in-line torque transducer without
risk.
MANUAL ORGANIZATION
This section gives an overview of the structure of the manual and the information contained therein.
Some information has been deliberately repeated in different sections of the document to minimize
cross-referencing and to facilitate understanding through reiteration.
The structure of the manual is as follows:
Chapter 1 : INTRODUCTION – Contains the technical data sheets for Magtrol’s TM In-Line
Torque Transducers, which describe the units and provide detailed technical
characteristics.
Chapter 2 : INSTALLATION / CONFIGURATION – Provides information needed for the setup
of the TM Transducers in a test system, and their integration with Magtrol electronic
control units.
Chapter 3 : OPERATING PRINCIPLES – Information pertaining to theory of operation
including details about the transducer's architecture, speed conditioning chain and
built-in self-test circuit.
Chapter 4 : MAINTENANCE / REPAIR – Provides information on maintenance and repair
procedures, should the need arise.

vi
Magtrol TM Series In-Line Torque TransducersPreface
CONVENTIONS USED IN THIS MANUAL
The following symbols and type styles may be used in this manual to highlight certain parts of the
text:
Note: This is intended to draw the operator’s attention to complementary
information or advice relating to the subject being treated. It
introduces information enabling the correct and optimal functioning
of the product to be obtained.
Caution : this is used to draw the operator's attention to information,
direCtives, proCedures, etC. whiCh, if ignored, may result in damage
being Caused to the material being used. the assoCiated text
desCribes the neCessary preCautions to take and the ConsequenCes
that may arise if the preCautions are ignored.
Warning! this introduces directives, procedures,
precautionary measures, etc. Which must Be
eXecuted or folloWed With the utmost care
and attention, otherWise the personal safety
of the operator or third parties may Be put
at risk. the reader must aBsolutely take note
of the accompanying teXt, and act upon it,
Before proceeding further.

1
1. Introduction
1.1 GENERAL INFORMATION
The TM Series In-Line Torque Transducers represent the new generation of high-precision torque
sensors with integrated electronic processing circuitry developed by Magtrol. The TM Series
transducers are available in three versions: TMB, TM and TMHS. TMB for all standard applications,
TM for high-precision applications and TMHS for high-speed applications.
The TM 300 Series includes transducers with the following torque ratings: 0.1 N·m, 0.2 N·m, 0.5
N·m, 1 N·m, 2 N·m, 5 N·m, 10 N·m, 20 N·m, 50 N·m, 100 N·m, 200 N·m, 500 N·m, 1 000 N·m,
2 000 N·m, 5 000 N·m and 10 000 N·m.
The TM Series In-Line Transducers, together with Magtrol's New TF Series Torque Flange
Transducers, offer a wide range of torque measurement requirements for the most demanding
applications.
1.2 DESCRIPTION
All TM Series In-Line Torque Transducers consist of a torque measuring shaft and built-in signal
processing electronics. These elements, along with two sealed bearings having lifelong lubrication,
are all contained in an aluminium housing which also supports the shaft.
The upper part of the unit contains the built-in electronics. This part is sealed according to the
IP44 standard and offers protection against splashed water. A Souriau connector allows the torque
transducer to be connected to an external signal processing unit—such as the Magtrol 3410 Torque
Display—via a special cable assembly.
Figure 1–1 TMB 313 In-Line Torque Transducer
TM Torque Transducers perform the following main functions:
1. Measurement of static and dynamic torque and detection of torque direction.
2. Measurement of the shaft's rotational speed and detection of rotational direction.
3. Self-check.
The transducer's integrated electronic circuitry filters the torque signal and its built-in self-test
function checks the operation of the measuring chain. Each transducer also has a built-in temperature
compensation circuit. This assures that the accuracy of the measured torque is maintained regardless
of operating temperature.

2
Magtrol TM Series In-Line Torque TransducersChapter 1 – Introduction
1.3 DATA SHEETS
1.3.1 TM 301 – TM 308
TM 301 – TM 308
Data Sheet
TM 301 – TM 308
In-Line Torque Transducers
1
www.magtrol.com
FEATURES
• Integrated Torque and Speed Conditioning
• Torque Range: 0.1 N·m to 20 N·m (0.07 lb·ft to 15 lb·ft)
• Accuracy: < 0.1%
• Overload Capacity: 200%
• Overload Limit: 400%
• High Speed Applications: up to 50,000 rpm
• Non-Contact (no sliprings)
• No Electronic Components in Rotation
• High Electrical Noise Immunity
• Single DC Power Supply: 20 VDC to 32 VDC
• Immediate Speed Detection
• Adjustable Torque Signal Frequency Limitation
• Built-in Test Function
• Stainless Steel Shaft
• EMC Susceptibility Conforms to European Standards
DESCRIPTION
Magtrol’s In-Line Torque Transducers provide extremely
accurate torque and speed measurement over a very broad range.
Each model has an integrated conditioning electronic module
providing a 0 to ±10 VDC torque output and an open collector
speed output. Magtrol Torque Transducers are very reliable,
providing high overload protection, excellent long term stability
and high noise immunity.
All transducer models employ our unique non-contact
differential transformer torque measuring technology. This
measuring technology offers many benefits, most notably that
no electronic components rotate during operation.
To provide customers with several price/performance options,
Magtrol offers three torque transducer models: basic accuracy
(TMB series), high accuracy (TM series) and high speed with
high accuracy (TMHS).
Each transducer consists of a hardened stainless steel shaft with
smooth shaft ends, an anodized aluminium housing containing
the guide bearings and an electronic measurement conditioner.
The integrated electronic circuit, supplied by single DC voltage,
provides torque and speed signals without any additional
amplifier. Connections are made by means of a 6-pole male
connector mounted on the housing, and fixed mounting is
enabled by mounting holes located on the transducer.
APPLICATIONS
TM, TMB and TMHS Series Torque Transducers provide
dynamic torque and speed measurement of:
• Propellers - aerospace, marine and helicopter
• Windshield wipers, electrical windows, starters,
generators and brakes in automobile industry
• Pumps - water and oil
• Reduction gears and gearboxes
• Clutches
• Motorized valves
• Drills, pneumatic tools and other machine tools
Model TM 307
Torque Transducer
BASIC SYSTEM CONFIGURATION
TORQUE
TRANSDUCER
TM 301 – TM 308
Power Supply 20 to 32 VDC / 100 mA max.
Speed
Torque 0 to ±10 VDC (max.)
Test

3
Magtrol TM Series In-Line Torque Transducers Chapter 1 – Introduction
2
TM 301 – TM 308
series ratings
The ratings in the following table apply to all standard Torque Transducer models 301–308, unless otherwise noted.
moDel ratings
The ratings in the following table apply to all Torque Transducer series (TM, TMHS and TMB).
Specifications
Standard Version TM Series TMHS Series TMB Series
TORQUE MEASUREMENT
Rated Torque (RT) 0 to ±100% of RT
Maximum Dynamic Torque Peak Value
(Overload Capacity) 0 to ±200% of RT
Maximum Dynamic Torque Without Damage
(Overload Limit) 0 to ±400% of RT
Combined Error of Linearity and
Hysteresis
to 100% of RT
< ±0.1% of RT
(0.2% for TM 301) < ±0.1% of RT < ±0.1% of RT
Combined Error of Linearity and
Hysteresis from 100% to 200% of RT
< ±0.1% of
measured value
(0.2% for TM 301)
< ±0.1% of
measured value
< ±0.15% of
measured value
Temperature Influence on the Zero/
Sensitivity:
• In the Compensated Range +10 °C to +60 °C < ±0.1% of RT/10K < ±0.2% of RT/10K
• In the Compensated Range -25 °C to +80 °C < ±0.2% of RT/10K < ±0.4% of RT/10K
Influence of Speed on the Zero Torque
Signal < ±0.01% of RT/1000 rpm < ±0.02% of RT/1000 rpm
Long-term Stability of Sensitivity < ±0.05% of RT/year < ±0.1% of RT/year
SPEED MEASUREMENT
Rated Range of Use 1 to 20,000 rpm TMHS 303: 1 to 40,000 rpm
TMHS 304-308: 1 to 50,000 rpm 1 to 6,000 rpm
Number of Teeth 60 Z
Minimum Speed Detection 1 rpm
ENVIRONMENT
Storage Temperature Range -40 °C to +100 °C
Operating Temperature Range -40 °C to +85 °C
Mechanical Shock according to IEC 68.2.27 / Class D3
Vibration according to IEC 68.2.6 / Class D3
Protection Class IP 44
MECHANICAL CHARACTERISTICS
Shaft Ends smooth
Balancing Quality G1 according to ISO 1940 G2.5 according to
ISO 1940
INPUT AND OUTPUT SIGNALS
Power Supply (max. voltage / current) 20 to 32 VDC / 100 mA
Torque Output (rated / max.) ±5 / ±10 VDC
Filter Cutoff (frequency) 5000, 2500, 1000, 500, 200, 100, 40, 20, 10, 5, 2, 1 Hz
Speed Output (frequency) open collector (15 Ω
in series), max. 30 VDC, protected against short-circuits
CONNECTORS
Counter Connector (female) optional (P/N 957.11.08.0081)
* Models 301 and 302 available in TM Series only.
Model Nominal Rated Torque Torsional Stiffness Moment of Inertia Weight
N·m lb·ft N·m/rad lb·ft/rad kg·m² lb·ft·s² kg lb
301 * 0.1 0.07 29 21 2.50 × 10-5 1.84 × 10-5 1.1 2.43
302 * 0.2 0.15 29 21 2.50 × 10-5 1.84 × 10-5 1.1 2.43
303 0.5 0.37 66 48 2.55 × 10-5 1.88 × 10-5 1.1 2.43
304 1 0.7 145 107 2.82 × 10-5 2.07 × 10-5 1.2 2.65
305 2 1.5 290 214 2.91 × 10-5 2.14 × 10-5 1.2 2.65
306 5 3.7 725 535 3.08 × 10-5 2.27 × 10-5 1.2 2.65
307 10 7.4 1450 1069 2.63 × 10-5 1.94 × 10-5 1.2 2.65
308 20 15 2900 2139 2.66 × 10-5 1.96 × 10-5 1.2 2.65

4
Magtrol TM Series In-Line Torque TransducersChapter 1 – Introduction
3
TM 301 – TM 308
Specifications
Dimensions
E
60°
F
G
H
L P
Q
R
S
M CC
U
V
W
X FF
Y GG
CAUTION!
ROTATING PARTS
IN OPERATION.
STOP SYSTEM BEFORE
PERFORMING
MAINTENANCE.
AA
N
DD
EE
A
B
C
F
D
E
N
J
K
A
BC
DT
NOTE:
Dimensions are the same for every series (TM, TMHS, TMB).
Original dimensions are in Metric units. Dimensions converted to English have been rounded up to 3 or 4 decimal places.
operating principles
The measuring system, based on the principle of a variable,
torque-proportional transformer coupling, consists of two
concentric cylinders shrunk on the shaft on each side of the
shaft’s deformation zone, and two concentric coils attached
to the housing.
Both cylinders have a circularly disposed coinciding row of
slots and rotate with the shaft inside the coils. An alternating
current with the frequency of 20 kHz flows through the primary
coil. When no torque is applied, the slots on the two cylinders
fail to overlap. When torque is applied, the deformation zone
undergoes an angular deformation and the slots begin to
overlap. Thus a torque-proportional voltage is on the secondary
coil. The conditioning electronic circuit incorporated in the
transducer converts the voltage to a nominal torque signal
of 0 to ±5 VDC. A low-pass filter (Butterworth/2nd order),
adjustable from 5 kHz to 1 Hz, allows tuning of the torque
signal frequency limitation.
An optical sensor reads the speed on a toothed path machined
directly on the measuring system. The electronic conditioner
outputs a frequency signal proportional to the shaft rotational
speed. An active circuit compensates the zero and sensitivity
temperature drifts within a tolerance of 0.1% / 10 K.
Model units Ø A Ø B Ø C Ø D E F G H J K L M N P Q
301–303
mm 60 42g6 2.12 0.1 --- 1.9 --- --- 13.2 7.8 5 114 60 5 9
in 2.362 1.6533
1.6526 0.083 0.004 --- 0.075 --- --- 0.520 0.307 0.197 4.488 2.362 0.197 0.354
304–308
mm 60 42g6 6.7 4.3 M4 3.2 10 14 21.2 10.8 5 136 60 5 12
in 2.362 1.6533
1.6526 0.264 0.169 M4 0.126 0.394 0.551 0.835 0.425 0.197 5.354 2.362 0.197 0.472
Model units R S Ø T U V W X Y AA CC DD EE FF GG
301–303
mm 14 12 6h6 15 10 M5 7.5 45 100 87 35
(
0
-0.05
) 30 7.5 45
in 0.551 0.472 0.2362
0.2359 0.591 0.394 M5 0.295 1.772 3.937 3.425 1.3779
1.3760 1.181 0.295 1.772
304–308
mm 22 20 10h6 15 10 M5 7.5 45 100 87 35
(
0
-0.05
) 30 ±0.02 7.5 45
in 0.866 0.787 0.3937
0.3933 0.591 0.394 M5 0.295 1.772 3.937 3.425 1.3779
1.3760
1.1819
1.1803 0.295 1.772
60°
C
DF
TM 301–303
Shaft Detail
Permitted
Axial Thrust

5
Magtrol TM Series In-Line Torque Transducers Chapter 1 – Introduction
4
TM 301 – TM 308
system options anD accessories
Couplings
When Magtrol TMB, TM and TMHS Series Torque Transducers
are to be mounted in a drive train, double-element miniature
couplings are the ideal complement, although single-element
couplings can be used for low speed applications. Several
manufacturers provide adequate couplings for both supported
and suspended drive train installations. The criteria for selecting
appropriate couplings for torque measurement is as follows:
• High torsional spring rate: Ensures a high torsional
stiffness and angular precision (should be greater than
three times the torque transducer stiffness)
• Clamping quality (should be self-centering and of
adequate strength)
• Speed range
• Balancing quality (according to speed range)
• Alignment capability
The higher the speed of the application, the more care is required in
selecting the coupling and assembling (alignment and balancing)
the drive train configuration. Your Magtrol sales representative
can assist you in choosing the right coupling for your transducer.
Torque Speed Box
Magtrol’s TSB Torque Speed Box allows data acquisition
from two torque transducers simultaneously and provides the
torque’s analog signal output and speed’s TTL signal output.
Torque Transducer Displays
Magtrol offers two different Torque Displays (Models 3410 and
6400) which supply power to any TM/TMHS/TMB Transducer
and display torque, speed and mechanical power. Features
include:
• Adjustable English, metric and SI torque units
• Large, easy-to-read vacuum fluorescent display
• Built-in self-diagnostic tests
• Overload indication
• Tare function
• RS-232 interface
• Torque and speed outputs
• Closed-box calibration
• Includes Magtrol Torque 1.0 Software
The Model 6400 Display has the following additional features:
• Pass/fail torque-speed-power testing capabilities
• RS-232 and IEEE-488 interface
• Auxiliary analog input
Torque 1.0 Software
Magtrol’s Torque 1.0 Software is an easy-to-use Windows®
executable program, used to automatically collect torque, speed
and mechanical power data. The data can be printed, displayed
graphically or quickly saved as a Microsoft® Excel spreadsheet.
Standard features of Torque 1.0 include: peak torque capture,
multi-axes graphing, measured parameter vs. time, adjustable
sampling rates and polynomial curve fitting.
Accessories Model #
Torque Transducer Connector Cable (5/10/20
m) ER 113
A
B
C
F
D
E
CAUTION!
ROTATING PARTS
IN OPERATION.
STOP SYSTEM BEFORE
PERFORMING
MAINTENANCE.
TM SERIES
TORQUE TRANSDUCER
Unit Under Test
Coupling Coupling
A
B
C
F
D
E
CAUTION!
ROTATING PARTS
IN OPERATION.
STOP SYSTEM BEFORE
PERFORMING
MAINTENANCE.
TM SERIES
TORQUE TRANSDUCER
Unit Under Test
Coupling Coupling
Supported Installation
Mandatory for high speed applications.
Suspended Installation
For low speed applications only, uses single-element
couplings to create a shorter drive train.
PC-Based System Configuration
Torque Transducer with Model 3410 Display
and Torque 1.0 Software
TRANSDUCER
SPEED TORQUE
Model 3410
Torque Display
TM Series
Torque Transducer
PC
Torque 1.0
Software
RS-232C
MAGTROL
SYSTEM SELECT TARE
Specifications

6
Magtrol TM Series In-Line Torque TransducersChapter 1 – Introduction
1.3.2 TM 309 – TM 313
TM 309 – TM 313
Data Sheet
TM 309 – TM 313
In-Line Torque Transducers
1
www.magtrol.com
FEATURES
• Integrated Torque and Speed Conditioning
• Torque Rating: 20 N·m to 500 N·m (37 lb·ft to 369 lb·ft)
• Accuracy: < 0.1%
• Overload Capacity: 200%
• Overload Limit: 400%
• High Speed Applications: up to 32,000 rpm
• Non-Contact (no sliprings)
• No Electronic Components in Rotation
• High Electrical Noise Immunity
• Single DC Power Supply: 20 VDC to 32 VDC
• Immediate Speed Detection
• Adjustable Torque Signal Frequency Limitation
• Built-in Test Function
• Stainless Steel Shaft
• EMC Susceptibility Conforms to European Standards
DESCRIPTION
Magtrol’s In-Line Torque Transducers provide extremely
accurate torque and speed measurement over a very broad range.
Each model has an integrated conditioning electronic module
providing a 0 to ±10 VDC torque output and an open collector
speed output. Magtrol Torque Transducers are very reliable,
providing high overload protection, excellent long term stability
and high noise immunity.
All transducer models employ our unique non-contact
differential transformer torque measuring technology. This
measuring technology offers many benefits, most notably that
no electronic components rotate during operation.
To provide customers with several price/performance options,
Magtrol offers three torque transducer models: basic accuracy
(TMB series), high accuracy (TM series) and high speed with
high accuracy (TMHS).
Each transducer consists of a hardened stainless steel shaft with
smooth or splined shaft ends, an anodized aluminium housing
containing the guide bearings and an electronic measurement
conditioner. The integrated electronic circuit, supplied by single
DC voltage, provides torque and speed signals without any
additional amplifier. The transducer is a stand-alone measuring
chain. Connections are made by means of a 6-pole male
connector mounted on the housing. A removable aluminium
base—delivered as standard with TM and TMHS models, and
as an option for TMB transducers—allows fixed mounting of
the transducer.
APPLICATIONS
TM, TMB and TMHS Series Torque Transducers provide
dynamic torque and speed measurement of:
• Propellers - aerospace, marine and helicopter
• Windshield wipers, electrical windows, starters,
generators and brakes in automobile industry
• Pumps - water and oil
• Reduction gears and gearboxes
• Clutches
• Motorized valves
• Drills, pneumatic tools and other machine tools
Model TM 313
Torque Transducer
BASIC SYSTEM CONFIGURATION
TORQUE
TRANSDUCER
TM 309 – TM 313
Power Supply 20 to 32 VDC / 100 mA max.
Speed
Torque 0 to ±10 VDC (max.)
Test

7
Magtrol TM Series In-Line Torque Transducers Chapter 1 – Introduction
2
TM 309 – TM 313
series ratings
The ratings in the following table apply to all standard Torque Transducer models 309–313, except where specifically noted.
moDel ratings
The ratings in the following table apply to all Torque Transducer series (TM, TMHS and TMB).
Specifications
* The weight for TMB series transducers ordered without an optional foot mount is slightly lower.
Standard Version TM Series TMHS Series TMB Series
TORQUE MEASUREMENT
Rated Torque (RT) 0 to ±100% of RT
Maximum Dynamic Torque Peak Value
(Overload Capacity) 0 to ±200% of RT
Maximum Dynamic Torque Without Damage
(Overload Limit) 0 to ±400% of RT
Combined Error of Linearity and Hysteresis
to 100% of RT < ±0.1% of RT < ±0.1% of RT < ±0.1% of RT
Combined Error of Linearity and Hysteresis
from 100 to 200% of RT
< ±0.1% of
measured value
< ±0.1% of
measured value
< ±0.15% of
measured value
Temperature Influence on the Zero/
Sensitivity:
• In the Compensated Range +10 °C to +60 °C < ±0.1% of RT/10K < ±0.2% of RT/10K
• In the Compensated Range -25 °C to +80 °C < ±0.2% of RT/10K < ±0.4% of RT/10K
Influence of Speed on the Zero Torque
Signal < ±0.01% of RT/1000 rpm < ±0.02% of RT/1000 rpm
Long-term Stability of Sensitivity < ±0.05% of RT/year < ±0.1% of RT/year
SPEED MEASUREMENT
Rated Range of Use models 309–311 1 to 10,000 rpm 1 to 32,000 rpm 1 to 4,000 rpm
models 312–313 1 to 10,000 rpm 1 to 24,000 rpm 1 to 4,000 rpm
Number of Teeth 60 Z
Minimum Speed Detection 1 rpm
ENVIRONMENT
Storage Temperature Range -40 °C to +100 °C
Operating Temperature Range -40 °C to +85 °C
Mechanical Shock according to IEC 68.2.27 / Class D3
Vibration according to IEC 68.2.6 / Class D3
Protection Class IP 44
MECHANICAL CHARACTERISTICS
Shaft Ends
model 309 smooth
models 310–311 smooth smooth keyway
models 312–313 smooth or splined smooth or splined keyway
Balancing Quality G1 according to ISO 1940 G2.5 according to ISO
1940
Foot Support (Base Mount) included included optional
INPUT AND OUTPUT SIGNALS
Power Supply (max. voltage / current) 20 to 32 VDC / 100 mA
Torque Output (rated / max.) ±5 / ±10 VDC
Filter Cutoff (frequency) 5000, 2500, 1000, 500, 200, 100, 40, 20, 10, 5, 2, 1 Hz
Speed Output (frequency) open collector (15 Ω in series), max. 30 VDC, protected against short-
circuits
CONNECTORS
Counter Connector (female) optional (P/N 957.11.08.0081)
Model Nominal Rated Torque Torsional Stiffness Moment of Inertia Weight *
N·m lb·ft N·m/rad lb·ft/rad kg·m² lb·ft·s² kg lb
309 20 15 2.4 × 1031.770 × 1031.49 × 10-4 1.03 × 10-4 2.5 5.51
310 50 37 5.7 × 1034.204 × 1031.52 × 10-4 1.12 × 10-4 2.5 5.51
311 100 74 1.14 × 1048.408 × 1031.55 × 10-4 1.14 × 10-4 2.5 5.51
312 200 148 3.82 × 1042.82 × 1044.85 × 10-4 3.57 × 10-4 4.1 9.04
313 500 369 9.58 × 1047.07 × 1045.16 × 10-4 3.80 × 10-4 4.4 9.70

8
Magtrol TM Series In-Line Torque TransducersChapter 1 – Introduction
3
TM 309 – TM 313
Dimensions
A
B
C
F
D
E
CAUTION!
ROTATING PARTS
IN OPERATION.
STOP SYSTEM BEFORE
PERFORMING
MAINTENANCE.
E
60°
F
G
HQ
R
M CC
V
WX
Y
Z
GG
AA
N
DD
EE
N
J
K
A*
B
CD
T
HH
S
Permitted
Axial Thrust
L
P
U
* Centering Seat
LL
JJ
KK FF
NOTE:
Original dimensions are in Metric units.
Dimensions converted to English have
been rounded up to 3 or 4 decimal places.
The measuring system, based on the principle of a variable, torque-
proportional transformer coupling, consists of two concentric
cylinders shrunk on the shaft on each side of the shaft’s deformation
zone, and two concentric coils attached to the housing.
Both cylinders have a circularly disposed coinciding row of
slots and rotate with the shaft inside the coils. An alternating
current with the frequency of 20 kHz flows through the primary
coil. When no torque is applied, the slots on the two cylinders
fail to overlap. When torque is applied, the deformation zone
undergoes an angular deformation and the slots begin to overlap.
Thus a torque-proportional voltage is on the secondary coil. The
conditioning electronic circuit incorporated in the transducer
converts the voltage to a nominal torque signal of 0 to ±5 VDC. A
low-pass filter (Butterworth/2nd order), adjustable from 5 kHz to
1 Hz, allows tuning of the torque signal frequency limitation.
An optical sensor reads the speed on a toothed path machined
directly on the measuring system. The electronic conditioner
outputs a frequency signal proportional to the shaft rotational
speed. An active circuit compensates the zero and sensitivity
temperature drifts within a tolerance of 0.1% / 10 K.
operating principles
Model units U V W X Y Z AA CC DD EE FF GG HH Ø JJ KK LL
309/X11
mm 29.4 12 76 10 110 130 74 87 60
(
0
-0.05
)
45±0.025 8 74 90±0.05 6.6 M5×10 20
in 1.157 0.472 2.992 0.394 4.331 5.118 2.913 3.425 2.3622
2.3603
1.7726
1.7707 0.315 2.913 3.5453 3.5413 0.260 M5×0.394 0.787
310/X11
mm 39.4 12 76 10 110 130 74 87 60
(
0
-0.05
)
45±0.025 8 74 90±0.05 7 M5×10 20
in 1.551 0.472 2.992 0.394 4.331 5.118 2.913 3.425 2.3622
2.3603
1.7726
1.7707 0.315 2.913 3.5453 3.5413 0.276 M5×0.394 0.787
311/X11
mm 44.4 12 76 10 110 130 74 87 60
(
0
-0.05
)
45±0.025 8 74 90±0.05 7 M5×10 20
in 1.748 0.472 2.992 0.394 4.331 5.118 2.913 3.425 2.3622
2.3603
1.7726
1.7707 0.315 2.913 3.5453 3.5413 0.276 M5×0.394 0.787
312/X11
mm 53.8 18 83 10 119 139 80 87 75
(
0
-0.05
)
50±0.025 10 80 100±0.05 9 M6×8 26
in 2.118 0.709 3.268 0.394 4.685 5.472 3.15 3.425 2.9527
2.9508
1.9695
1.9675 0.394 3.15 3.9390 3.9350 0.354 M6×0.315 1.024
313/X11
mm 63.8 18 83 10 119 139 80 87 75
(
0
-0.05
)
50±0.025 10 80 100±0.05 9 M6×8 26
in 2.512 0.709 3.268 0.394 4.685 5.472 3.15 3.425 2.9527
2.9508
1.9695
1.9675 0.394 3.15 3.9390 3.9350 0.354 M6×0.315 1.024
Model units Ø A Ø B Ø C Ø D E F G H J K L M N P Q R S Ø T
309/X11
mm 82g6 64 9.6 6.4 M6 5.0 16 21 26.2 16.8 86 170.4 60 20 15 26.4 25 20h6
in 3.2283
3.2270 2.52 0.378 0.252 M6 0.197 0.63 0.827 1.031 0.661 3.386 6.709 2.362 0.787 0.591 1.039 0.984 0.7874 0.7869
310/X11
mm 82g6 64 9.6 6.4 M6 5.0 16 21 36.2 16.8 86 190.4 60 20 15 36.4 35 20h6
in 3.2283
3.2270 2.52 0.378 0.252 M6 0.197 0.63 0.827 1.425 0.661 3.386 7.496 2.362 0.787 0.591 1.433 1.378 0.7874 0.7869
311/X11
mm 82g6 64 9.6 6.4 M6 5.0 16 21 41.2 16.8 86 200.4 60 20 15 41.4 40 20h6
in 3.2283
3.2270 2.52 0.378 0.252 M6 0.197 0.63 0.827 1.622 0.661 3.386 7.89 2.362 0.787 0.591 1.63 1.575 0.7874 0.7869
312/X11
mm 96g6 78 14.9 10.5 M10 7.5 22 30 46.4 22.8 91 228.0 60 25 21 46.8 45 30h6
in 3.7791
3.7782 3.071 0.587 0.413 M10 0.295 0.866 1.181 1.827 0.898 3.583 8.976 2.362 0.984 0.827 1.842 1.772 1.1811 1.1806
313/X11
mm 96g6 78 14.9 10.5 M10 7.5 22 30 56.4 22.8 91 248.0 60 25 21 56.8 55 30h6
in 3.7791
3.7782 3.071 0.587 0.413 M10 0.295 0.866 1.181 2.22 0.898 3.583 9.764 2.362 0.984 0.827 2.236 2.165 1.1811 1.1806
transDucers with smooth shaFt

9
Magtrol TM Series In-Line Torque Transducers Chapter 1 – Introduction
4
TM 309 – TM 313
Dimensions
NOTE:
Original dimensions are in Metric
units. Dimensions converted to
English have been rounded up to
3 or 4 decimal places.
MM
T*
QQ
RR*
NN
PP
QQ - Splines
according to
DIN 5481
January 1952
A
B
C
F
D
E
CAUTION!
ROTATING PARTS
IN OPERATION.
STOP SYSTEM BEFORE
PERFORMING
MAINTENANCE.
E
60°
F
G
H Q
R
M CC
V
W X
Y
Z
GG
AA
N
DD
EE
N
J
K
A*
B
C D
HH
S
Permitted
Axial Thrust
L
P
U
* Centering Seat
LL
JJ
KK FF
* Centering
Seat
options
Flanges
Flanges are optional for torque transducers with splined shaft
ends. Flange drawing is available on request.
Description Model P/N
Flange for Model 312/X21 FTM 212 415-212-960-011
Flange for Model 313/X21 FTM 213 415-213-960-011
Model units Ø A Ø B Ø C Ø D E F G H J K L M N
312/X21
mm 96g6 78 14.9 10.5 M10 7.5 22 30 40.4 22.8 91 216 60
in 3.7791
3.7782 3.071 0.587 0.413 M10 0.295 0.866 1.181 1.591 0.898 3.583 8.504 2.362
313/X21
mm 96g6 78 14.9 10.5 M10 7.5 22 30 52.4 22.8 91 240 60
in 3.7791
3.7782 3.071 0.587 0.413 M10 0.295 0.866 1.181 2.063 0.898 3.583 9.449 2.362
Model units P Q R S Ø T U V W X Y Z AA CC
312/X21
mm 25 21 40.8 39 22h6 47.8 18 83 10 119 139 80 87
in 0.984 0.827 1.606 1.535 0.8661
0.8656 1.882 0.709 3.268 0.394 4.685 5.472 3.15 3.425
313/X21
mm 25 21 52.8 51 22h6 59.8 18 83 10 119 139 80 87
in 0.984 0.827 2.079 2.008 0.8661
0.8656 2.354 0.709 3.268 0.394 4.685 5.472 3.15 3.425
Model units DD EE FF GG HH Ø JJ KK LL MM NN PP QQ Ø RR
312/X21
mm 75
(
0
-0.05
)
50±0.025 10 80 100±0.05 9 M6×8 26 35 24 4 26×30 31h6
in 2.9527
2.9508
1.9695
1.9675 0.394 3.15 3.9390 3.9350 0.354 M6×0.315 1.024 1.378 0.945 0.157 26×30 1.2205 1.2198
313/X21
mm 75
(
0
-0.05
)
50±0.025 10 80 100±0.05 9 M6×8 26 47 36 4 26×30 31h6
in 2.9527
2.9508
1.9695
1.9675 0.394 3.15 3.9390 3.9350 0.354 M6×0.315 1.024 1.850 1.417 0.157 26×30 1.2205 1.2198
transDucers with splineD shaFt

10
Magtrol TM Series In-Line Torque TransducersChapter 1 – Introduction
5
TM 309 – TM 313
Dimensions
options
Foot Mount
For foot mount dimensions, refer to U–Z and DD–JJ
dimensions of the smooth shaft transducer.
Description Model P/N
Foot mount for models 310–311 PTM 310 415-309-950-011
Foot mount for models 312–313 PTM 312 415-312-950-011
tmB transDucers with Keyway
NOTE:
Original dimensions are in Metric units. Dimensions converted to
English have been rounded up to 3 or 4 decimal places.
A
B
C
F
D
E
CAUTION!
ROTATING PARTS
IN OPERATION.
STOP SYSTEM BEFORE
PERFORMING
MAINTENANCE.
E
60°
F
G
HQ
R
M CC
AA
N
N
J
K
A*
B
CD
T
S
Permitted
Axial Thrust
L
* Centering Seat
LL
KK
SS
UU
BB
P
W
Model units Ø A Ø B Ø C Ø D E F G H J K L M P
310/431
mm 82g6 64 9.6 6.4 M6 5.0 16 21 36.2 16.8 86 190.4 20
in 3.2283
3.2270 2.52 0.378 0.252 M6 0.197 0.63 0.827 1.425 0.661 3.386 7.496 0.787
311/431
mm 82g6 64 9.6 6.4 M6 5.0 16 21 41.2 16.8 86 200.4 20
in 3.2283
3.2270 2.52 0.378 0.252 M6 0.197 0.63 0.827 1.622 0.661 3.386 7.89 0.787
312/431
mm 96g6 78 14.9 10.5 M10 7.5 22 30 46.4 22.8 91 228.0 25
in 3.7791
3.7782 3.071 0.587 0.413 M10 0.295 0.866 1.181 1.827 0.898 3.583 8.976 0.984
313/431
mm 96g6 78 14.9 10.5 M10 7.5 22 30 56.4 22.8 91 248.0 25
in 3.7791
3.7782 3.071 0.587 0.413 M10 0.295 0.866 1.181 2.22 0.898 3.583 9.764 0.984
Model units N Q R S Ø T W AA BB CC KK LL SS UU
310/431
mm 60 15 36.4 35 20h6 76 74 32 87 M5×10 20 25 6h9
in 2.362 0.591 1.433 1.378 0.7874
0.7869 2.992 2.913 1.26 3.425 M5×0.394 0.787 0.984 0.2362 0.2350
311/431
mm 60 15 41.4 40 20h6 76 74 37 87 M5×10 20 25 6h9
in 2.362 0.591 1.63 1.575 0.7874
0.7869 2.992 2.913 1.457 3.425 M5×0.394 0.787 0.984 0.2362 0.2350
312/431
mm 60 21 46.8 45 30h6 83 80 42 87 M6×8 26 36 8h9
in 2.362 0.827 1.842 1.772 1.1811
1.1806 3.268 3.15 1.653 3.425 M6×0.315 1.024 1.417 0.3150 0.3135
313/431
mm 60 21 56.8 55 30h6 83 80 52 87 M6×8 26 36 8h9
in 2.362 0.827 2.236 2.165 1.1811
1.1806 3.268 3.15 2.047 3.425 M6×0.315 1.024 1.417 0.3150 0.3135

11
Magtrol TM Series In-Line Torque Transducers Chapter 1 – Introduction
6
TM 309 – TM 313
System Options
A
B
C
F
D
E
CAUTION!
ROTATING PARTS
IN OPERATION.
STOP SYSTEM BEFORE
PERFORMING
MAINTENANCE.
TM SERIES
TORQUE TRANSDUCER
Unit Under Test
Coupling Coupling
A
B
C
F
D
E
CAUTION!
ROTATING PARTS
IN OPERATION.
STOP SYSTEM BEFORE
PERFORMING
MAINTENANCE.
TM SERIES
TORQUE TRANSDUCER
Unit Under Test
Coupling Coupling
Supported Installation
Mandatory for high speed applications.
Suspended Installation
For low speed applications only, uses single-element
couplings to create a shorter drive train.
PC-Based System Configuration
Torque Transducer with Model 3410 Display
and Torque 1.0 Software
TRANSDUCER
SPEED TORQUE
Model 3410
Torque Display
TM Series
Torque Transducer
PC
Torque 1.0
Software
RS-232C
MAGTROL
SYSTEM SELECT TARE
Couplings
When Magtrol TMB, TM and TMHS Series Torque Transducers
are to be mounted in a drive train, double-element miniature
couplings are the ideal complement, although single-element
couplings can be used for low speed applications. Several
manufacturers provide adequate couplings for both supported
and suspended drive train installations. The criteria for selecting
appropriate couplings for torque measurement is as follows:
• High torsional spring rate: Ensures high torsional
stiffness & angular precision (should be > 3 times the
torque transducer stiffness)
• Clamping quality (should be self-centering & of
adequate strength)
• Speed range
• Balancing quality (according to speed range)
• Alignment capability
The higher the speed of the application, the more care is required in
selecting the coupling and assembling (alignment and balancing)
the drive train configuration. Your Magtrol sales representative
can assist you in choosing the right coupling for your transducer.
Torque Speed Box
Magtrol’s TSB Torque Speed Box allows data acquisition
from two torque transducers simultaneously and provides the
torque’s analog signal output and speed’s TTL signal output.
Torque Transducer Displays
Magtrol offers two different Torque Displays (Models 3410 and
6400) which supply power to any TM/TMHS/TMB Transducer
and display torque, speed and mechanical power. Features
include:
• Adjustable English, metric and SI torque units
• Large, easy-to-read vacuum fluorescent display
• Built-in self-diagnostic tests
• Overload indication
• Tare function
• RS-232 interface
• Torque and speed outputs
• Closed-box calibration
• Includes Magtrol Torque 1.0 Software
The Model 6400 Display has the following additional features:
• Pass/fail torque-speed-power testing capabilities
• RS-232 and IEEE-488 interface
• Auxiliary analog input
Torque 1.0 Software
Magtrol’s Torque 1.0 Software is an easy-to-use Windows®
executable program, used to automatically collect torque, speed
and mechanical power data. The data can be printed, displayed
graphically or quickly saved as a Microsoft® Excel spreadsheet.
Standard features of Torque 1.0 include: peak torque capture,
multi-axes graphing, measured parameter vs. time, adjustable
sampling rates and polynomial curve fitting.
Accessories Model #
Torque Transducer Connector Cable (5/10/20
m) ER 113
system options anD accessories

12
Magtrol TM Series In-Line Torque TransducersChapter 1 – Introduction
1.3.3 TM 314 – TM 317
TM 314 – TM 317
Data Sheet
TM 314 – TM 317
In-Line Torque Transducers
1
www.magtrol.com
FEATURES
• Integrated Torque and Speed Conditioning
• Torque Rating: 1000 to 10,000 N·m (737 to 7375 lb·ft)
• Accuracy: < 0.1% (depending on model)
• Overload Capacity: 200%
• Overload Limit: 400% (TM 317 up to 280%)
• High Speed Applications: up to 16,000 rpm
• Non-Contact (no sliprings)
• No Electronic Components in Rotation
• High Electrical Noise Immunity
• Single DC Power Supply: 20 VDC to 32 VDC
• Immediate Speed Detection
• Adjustable Torque Signal Frequency Limitation
• Built-in Test Function
• Stainless Steel Shaft
• EMC Susceptibility Conforms to European Standards
DESCRIPTION
Magtrol’s In-Line Torque Transducers provide extremely
accurate torque and speed measurement over a very broad range.
Each model has an integrated conditioning electronic module
providing a 0 to ±10 VDC torque output and an open collector
speed output. Magtrol Torque Transducers are very reliable,
providing high overload protection, excellent long term stability
and high noise immunity.
All transducer models employ our unique non-contact
differential transformer torque measuring technology. This
measuring technology offers many benefits, most notably that
no electronic components rotate during operation.
To provide customers with several price/performance options,
Magtrol offers two torque transducer models: high accuracy
(TM series) and high speed with high accuracy (TMHS).
Each transducer consists of a hardened stainless steel shaft
with smooth or splined shaft ends, an anodized aluminium
housing containing the guide bearings and an electronic
measurement conditioner. The integrated electronic circuit,
supplied by single DC voltage, provides torque and speed
signals without any additional amplifier. The transducer is
a stand-alone measuring chain. Connections are made by
means of a 6-pole male connector mounted on the housing.
A removable aluminium base, delivered as standard, allows
fixed mounting of the transducer.
APPLICATIONS
TM and TMHS Series Torque Transducers provide dynamic
torque and speed measurement of:
• Propellers - aerospace, marine and helicopter
• Windshield wipers, electrical windows, starters,
generators and brakes in automobile industry
• Pumps - water and oil
• Reduction gears and gearboxes
• Clutches
• Motorized valves
• Drills, pneumatic tools and other machine tools
Model TM 316
Torque Transducer
BASIC SYSTEM CONFIGURATION
TORQUE
TRANSDUCER
TM 314 – TM 317
Power Supply 20 to 32 VDC / 100 mA max.
Speed
Torque 0 to ±10 VDC (max.)
Test