User’s guide for DT-C001

DC Motors

Document No. 00308589-V1

 CONTENTS

1. RESOURCES FILE ................................................................................................................... 4

1.1 REMINDER .......................................................................................................................................................................... 5
1.2 COMPOSITION ..................................................................................................................................................................... 6
2 USER FILE ................................................................................................................................ 7
USER AND INSTRUCTION MANUAL ....................................................................................................................................... 7
2.1 STUDY OF THE ELECTRIC WINDOW D.C. MOTOR .................................................................................................................. 9
2.2 STUDY OF THE WING MIRROR D.C. MOTOR ........................................................................................................................ 12
3 PRACTICAL EXERCISES ...................................................................................................... 15
3.1 WIRE UP THE UNIT WHICH CONTROLS THE ELECTRIC WINDOW AND WING MIRROR MOTORS. ............................................ 16
DECLARATION OF CONFORMITY .............................................................................................. 18
 DC Motors

Direct current model

1. RESOURCES FILE

Principle of operation of a direct current (d.c.) motor

When a coil carrying a current (supplied by brushes and a commutator) is placed in a magnetic field, a
force couple (or pair of forces) is generated. This force couple creates a rotational torque which rotates
the coil through about 90 degrees. Since the direction of current flow in the coil does not change, then as
the coil rotates the rotational torque gradually reduces to zero once the coil has rotated through about 90
degrees (in this neutral zone, the coil is perpendicular to the field produced by the permanent magnets).

By winding a large number of similar coils around the armature (or rotor) the motor can rotate smoothly.
These coils are distributed evenly around the periphery of the armature so that torque is generated
irrespectively of the angle of rotation. Once the coils have reached the zone of neutral torque, the
direction of current flow must be reversed simultaneously in every coil of wire.

The direction of current flow is reversed by a commutator which, together with the brushes, transmits
current from the stationary part of the motor to the rotating part.

The main advantage offered by d.c. motors is their compatibility with the means used to regulate or vary
their speed, torque and direction of rotation: variable speed drives variateurs de vitesse. Another
advantage is that they can be connected directly to energy sources: lead-acid batteries, lithium-ion
batteries, etc.

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The main drawback of d.c. machines is wear of the rotating brush/commutator assembly. It is a complex
assembly to produce, and consumes energy. Another problem can arise with wound-rotor motors when
they are operated at high speed. Over time, the high centrifugal forces can break down the banding
which secures the coils to the rotor.

Some of these drawbacks have been partially overcome by producing motors with no iron in the rotor,
such as “disk” motors or low-inertia “coreless” motors, which are nonetheless always fitted with brushes.
The above drawbacks have been eliminated by the introduction of brushless motor technology moteurs
brushless, also known as “brushless d.c. motors” or brushless motors.

1.1 Reminder

Laplace’s law

A current-carrying conductor in a magnetic field experiences a force, the direction of which can be
determined using the “Laplace’s right-hand rule” (a variant on Fleming’s left-hand rule).

F=B*I*L

F Force in newtons
B Magnetic induction in teslas
I Current in the conductor in amps
L Length of the conductor in metres

The right-hand rule

To determine the direction of the force, point your

thumb, index finger and middle finger in directions
perpendicular to each other, as shown.

The thumb points in the direction of the field (the

direction of the lines of induction always run from N to
S when outside a magnet, and from S to N when
inside).

The middle finger points in the direction of the current

(and always in accordance with the convention for
current direction, i.e. from +ve to -ve).

The index finger then indicates the direction of the

force.

Make sure that you use your right hand and not your left hand. In fact, the left hand is used for another
rule.

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 DC Motors

1.2 Composition

STATOR (field magnet)

The stator stator generates a longitudinal and steady magnetic flux flux magnétique either due to current
flowing through coils wound around the stator or as a result of the stator being a permanent magnet
aimants. It is thus also known as the “field magnet” since it generates the magnetic field within the
machine. It is secured to the motor housing.

Brushes
The brushes distribute electricity to the rotor

Magnets
The magnets create the magnetic field They are made from an assembly or lamination of strips of
electrical steel, (+ 0.5 mm) thick, insulated from each other by natural oxidation. An alternative is the use
of pole magnets.

ROTOR (armature)
The wound rotor rotor connected to a rotating commutator collecteur rotatif reverses the polarity polarité
in each rotor winding at least once per rotation, so as to create a transverse magnetic flux in quadrature
to the flux generated by the stator. The rotor windings are also known as armature windings.
The rotation of the armature provides the useful motion generated by the motor.

Commutator
This component receives the electrical current from the brushes.

Wound components
These components are produced by winding insulated copper wire (insulating varnish) around a pole
body so as to produce an electromagnet.

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2 USER FILE
USER AND INSTRUCTION MANUAL
Installing and starting up benchtop learning module DT-C001
Connect the module to the power supply provided.
Wire up the d.c. motors to operate the system as indicated in the user manual supplied with module DT-
C001.
There are moving components on module DT-C001.

Environment
Module DT-C001 is designed for benchtop use. It must be installed in a dry place away from dust, steam and
combustion fumes.
The module requires approximately 400–500 lux of light
The module must be placed in a practical exercise room. Its operating noise level does not exceed 70
decibels.
The benchtop learning module is protected against potential user error.

Calibrating and maintaining benchtop learning module DT-C001

Calibrating: set in the factory.
Maintenance frequency: none.
Cleaning: use a clean and very soft cloth and a window-cleaning product.

Number of work stations and position of user

Module DT-C001 is considered to be a single work station.
The module user will remain seated throughout the practical exercise.

Lockout/Tagout procedure
Switch off the power supply by setting the switch to 0.
Unplug the 230 V connector.
Check that there is no current by actuating the d.c. motor control switches, and check the bi-coloured LEDs –
if nothing happens and the LED are off, then there is no current in the module.
Store module DT-C001 in a secure room while out of use.

Residual risk
For the entire duration of the practical session, the trainee shall work on the front of the learning module.

Transporting module DT-C001

The benchtop learning module must be switched off and disconnected before transport.

The module should only be opened by certified

and authorised persons

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 DC Motors

Module DT-C0001 comprises two dc. motors – one which operates an electric window and one which
adjusts the wing mirror position. The controls for the electric window and wing mirrors are located in the
centre of the module.

Protective features incorporated into the module ensure that the user cannot damage the module by
inadvertently reversing a polarity or applying an over-voltage.

Part equivalence table

Product name Device number Ref. PSA Ref.

Electric window motor 6040 9223 52

Wing mirror motor 6415 6602 38

Control unit 6036 6552 WP

Terminal allocation for the 7V Black connector block

7 CHANNELS Black

1A = Ground
2A = Spare
3A = +12 V
4A = Motor control
1B = Spare
2B = Spare
3B = Motor control

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2.1 Study of the electric window d.c. motor

Wiring

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 DC Motors

Reversing the direction of rotation.

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 DT-C001

Wiring diagram

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 DC Motors

2.2 Study of the wing mirror d.c. motor

Wiring

²
Wiring example for Up/right movement

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 DT-C001

Wiring diagram

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 DC Motors

Terminal allocation for the 18V Black connector block

18 CHANNELS Black

1 = Not connected
2 = Right/Left Wing Mirror Motor control
3 = Not connected
4 = Up/Down Wing Mirror Motor control
5 = Not connected
6 = Not connected
8 = +12 V
14 =Common

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 DT-C001

3 Practical exercises
To reverse the direction of rotation of a separately-excited d.c. motor, you must: (there may be
more than one solution):

X  Reverse the polarity at the armature terminals

 Reverse the polarity at the field magnet terminals
 Reverse the polarities at the terminals of both the armature and field magnet

According to Laplace’s right-hand rule, the thumb, index finger and middle finger relate
respectively to:

X  Field, force, current

 Force, field, current
 Force, current, field
 Field, current, force

The part of the motor which moves is called the: (there may be more than one solution):

X  Rotor
 Inductor
X  Armature
 Stator

The stationary part of the motor is called the: (there may be more than one solution):

 Rotor
X  Stator
 Commutator
X  Field magnet

In a d.c. shunt motor, which of these windings has the lowest resistance?

 Armature winding
X  Field magnet winding

What do you do to increase the speed of a separately-excited d.c. motor?

 Reduce the armature voltage

 Increase the field magnet voltage
X  Increase the armature voltage
The resisting torque for a separately-excited motor is increased slightly. What happens to the current in
the armature winding?

X  It increases
 It stays the same
 It reduces

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3.1 Wire up the unit which controls the electric window and wing mirror
motors.

If you’re not sure, refer to the wiring diagrams on pages 11 and 13.

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Wiring setup as per the manufacturer’s wiring diagram

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DECLARATION OF CONFORMITY
Via this declaration of conformity with the requirements stated in directive 2004/108/EC relating to
electromagnetic compatibility, the company:
S.A.S. ANNECY ELECTRONIQUE
Parc Altaïs – 1, rue Callisto
F74650 CHAVANOD

Declares that the product indicated below:

Make Model Product name

EXXOTEST DT-C001 BENCHTOP LEARNING MODULE: Study of the d.c.

motor

I - has been manufactured in accordance with the requirements of European directives:

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 Low Voltage Directive 2006/95/EC of 12 December 2006

 Machinery Directive 98/37/EC of 22 June 1998
 Electromagnetic Compatibility Directive 2004/108/EC of 15 December 2004

and meets the requirements of the following standard:

 NF EN 61326-1 of 07/1997 +A1 of 10/1998 +A2 of 09/2001

Electrical equipment for measurement, control and laboratory use. EMC requirements.

II – has been manufactured in compliance with the requirements of European directives relating
to the design of Electrical & Electronic Equipment (EEE) and the management of Waste
Electrical & Electronic Equipment (WEEE) in the EU:

 Directive 2002/96/EC of 27 January 2003 on waste electrical & electronic equipment

 Directive 2011/65/EC of 27 January 2003 on the restriction of the use of certain hazardous
substances in electrical and electronic equipment (ROHS).

Signed in Chavanod, France, on 2 June 2009

Stéphane Sorlin, Chairman

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 Latitude: 45° 53’ 49’’ / Longitude: 6° 4’ 57’’

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Original manual Document n° 00308589-V1

ANNECY ELECTRONIQUE, créateur et fabricant de matériel : Exxotest et Navylec.

Parc Altaïs - 1 rue Callisto - F 74650 CHAVANOD - Tel : 33 (0)4 50 02 34 34 - Fax : 33 (0)4 50 68 58 93
S.A.S. au Capital de 345 000€ - RC ANNECY 80 B 243 - SIRET 320 140 619 00042 - APE 2651B - N° TVA FR 37 320 140 619
ISO 9001 : 2008 N° FQA 4000142 par L.R.Q.A.