Siemens MASTERDRIVE

Siemens MASTERDRIVEs provide an excellent solution for

industrial applications worldwide. Water-cooled versions can be
used in areas with high ambient temperature or where external
air cooling is unavailable. MASTERDRIVEs can be used for
variable-speed control on motors rated from 1 to 10,000 HP.
MASTERDRIVEs are available for all major worldwide 3-phase
supply voltages: 208-230, 380-460, 500-575, 660-690 volts. The
Siemens MASTERDRIVEs can also be referred to by a model
series number, 6SE70.

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IEC and NEMA Protection Depending on the size of the unit, Siemens MASTERDRIVEs
are available in a variety of enclosures. In addition to the basic
MASTERDRIVE 6SE70, drives designated 6SE71 are built to
International Electrotechnical Commission (IEC) standards.
Drives designated 6SE72 are built to National Electrical
Manufacturers Association (NEMA) standards. IEC and NEMA
enclosure standards provide various degrees of protection to
personnel and equipment.

IEC Standards The IEC system of classification consists of the letters IP

followed by two numbers. The first number indicates the degree
of protection provided by the enclosure with respect to persons
and solid objects entering the enclosure. The second number
indicates the degree of protection against the ingress of water.

1st Number Description

0 Not Protected
1 Protected Against Objects Greater than 50 mm
2 Protected Against Objects Greater than 12 mm
3 Protected Against Objects Greater than 2.5 mm
4 Protected Against Objects Greater than 1.0 mm
5 Protected Against Dust
6 Dust Tight
2nd Number
0 Not Protected
1 Protected Against Dripping Water
2 Protected Against Dripping Water when Tilted up to 15°
3 Protected Against Spraying Water
4 Protected Against Splashing Water
5 Protected Against Water Jets
6 Protected Against Heavy Seas
Protected Against the Effects of Immersion for Specific
7
Time and Pressure
Protected Against Continuous Submersion Under
8
Conditions Specified by the Manufacturer

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IP Enclosures Available MASTERDRIVE IP Ratings Available
Compact IP20
Chassis IP00, IP20
IP20, IP21, IP23, IP24, IP43,
Cabinet
Prepared for IP54

NEMA Standards The National Electrical Manufacturers Association (NEMA) also

designates, by means of a type number, environmental
conditions an enclosure is suited for. MASTERDRIVEs are
available in NEMA 1, 4, and 12 enclosures.

NEMA Type Definition

Indoor use primarily to provide a degree of
1 protection against limited amounts of falling dirt.
Indoor or outdoor use primarily to provide a degree
of protection against windblown dust and rain,
4
splashing water, hose-directed water, and damage
from external ice formation.
Indoor or outdoor use primarily to provide a degree
of protection against corrosion, windblown dust
4X
and rain, splashing water, hose-directed water, and
damage from external ice formation.
Indoor use primarily to provide a degree of
12 protection against circulating dust, falling dirt, and
dripping noncorrosive liquids.

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Versions There are two versions of the MASTERDRIVEs product: vector
control (VC) and motion control (MC).

Vector Control (VC) One mode of operation in the MASTERDRIVEs is vector control
(VC), which is the focus of this part of the course. In the past, the
dynamic response of a DC motor was generally considered
significantly better than an AC motor. An AC motor, however, is
less expensive and requires less maintenance than a DC motor.
Using a complex mathematical motor model and proprietary
internal computer algorithms vector control is able to exert the
necessary control over an AC motor so that its performance is
equal to that of a DC motor. Vector control, flux vector, and field
orientation are terms that describe this specialized control
technique of AC drives.

Vector control drives have 4-quadrant operation and control

torque and speed continuously through zero speed, and can
hold a motor stationary against an applied torque. Speed control
is exact, even with varying loads. Speed control reaction time is
≤ 45 ms without tach feedback, and ≤ 20 ms with tach feedback.
Maximum torque is available up to base speed. Torque control
reaction time is ≤ 10 ms in torque control with feedback.

Motion Control (MC) A second mode of operation available on the MASTERDRIVEs

is motion control (MC). Servo drives are designed to operate
with a specific motor and are designed to achieve speed
precision and fast response to a speed change. Servo
applications typically have rapid start-stop cycles, require zero
speed holding torque and high accelerating torque from zero
speed, and are used positioning applications. In a packaging
machine, for example, material may have to start and stop at
various positions along a conveyor system.

The STEP 2000 course, Basics of General Motion Control,

provides more information on the Siemens motion control
(MC) drive.

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Ratings The following graph shows horsepower ratings available for
VC MASTERDRIVEs.

HP 1 30 5000 10,000

660V - 15% up to
690V + 15%
50/60Hz ± 6%
500V - 15% up to
575V + 15%
50/60Hz ± 6%
380V - 15% up to
460V + 15%
50/60Hz ± 6%
208V - 15% up to
230V + 15%
50/60Hz ± 6%

AC - AC (AC to AC) The terms AC - AC and DC - AC refers to methods of

configuring MASTERDRIVEs. AC - AC in the MASTERDRIVE VC
family refers to a single drive, connected to an AC source,
controlling an AC motor, an AC motor with a tach, or multimotor
applications. Various options allow for analog and encoder
tachometer types.

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DC - AC (DC to AC) The Siemens MASTERDRIVEs can also be configured so that a
common DC bus supplies power to several AC inverters.
Common DC bus systems also allow single and multimotor
combinations. This is referred to as the DC-AC version. An
advantage to this system is that energy regenerated by one
inverter can be consumed by another inverter on the same bus.

Braking Choices The dynamics of certain loads require four-quadrant operation.

Torque will always act to cause the rotor to run towards
synchronous speed. If the synchronous speed is suddenly
reduced, negative torque is developed in the motor. This could
occur, for example when a stop command is initiated and the
drive tries to slow down to bring the motor to a stop. The motor
acts like a generator by converting mechanical power from the
shaft into electrical power which is returned to the AC Drive.
This is known as regeneration, and helps slow the motor.
Braking occurs in quadrants II and IV. When equipped with an
optional braking unit, Siemens MASTERDRIVEs are capable of
four-quadrant operation.

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 One method of dealing with negative torque and the current it
produces is controlled deceleration. Voltage and frequency is
reduced gradually until the motor is at stop. This would be
similar to slowly removing your foot from the accelerator of a
car. Many applications, however, require the motor to stop
quicker, and the drive must be capable of handling the excess
energy produced by motor when this is done.

Rectifier Regenerative Another method of dealing with excessive regeneration is with

Front End a rectifier regenerative front end. Diodes in the converter
section are replaced with SCRs and a second regen bridge is
added. An SCR functions similarly to a diode rectifier, except
that it has a gate lead, which is used to turn the SCR on. This
allows the control logic to control when the converter bridge
and regen bridge are turned on.

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A simplified block diagram provides a clearer view of the regen
process. When the motor needs motoring energy to accelerate
or maintain speed against the inertia of a load, the converter
bridge is turned on. When the motor is in the regenerative
mode, it acts like a generator, supplying electrical energy back
to the DC link. When the DC link voltage reaches a
predetermined level the motoring SCRs are switched off and
the regen (generating) SCRs are switched on.

This allows the excess energy to be returned to the AC line in

the form of AC current.

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ACTIVE FRONT END An ACTIVE FRONT END (AFE) is another option available to
control regenerative voltage. With this option the diodes in the
converter bridge are replaced with IGBT modules and a Clean
Power Filter. The IGBT, controlled by control logic, operates in
both motoring and regenerating modes.

Harmonics are created by electronic circuits, such as the non-

linear loads of adjustable speed drives. Harmonics can cause
problems to connected loads. The base frequency is said to be
the fundamental frequency or first harmonic. Additional
harmonics that are superimposed on the fundamental
frequency are usually whole number multiples of the first
harmonic. The fifth harmonic of a 60 Hz power supply, for
example, is 300 Hz (60 x 5).

A distinct advantage of Siemens MASTERDRIVEs equipped

with AFE and a Clean Power Filter is they are optimally
harmonized with each other to eliminate harmonics and provide
a clean power supply. In addition, the Siemens AFE allows for
capacitive KVAR production which effectively compensates for
other inductive loads in an industrial plant. This helps reduce the
overall utility bill.

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Compact Units Compact units require the smallest mounting space. Units can
be DIN-G rail mounted side-by-side without spacing. There are
four sizes: A, B, C, and D. Compact units are available with
ratings from 3 to 50 HP (5.6 to 72 Amps) at 460 VAC.

The following table shows the size in millimeters and maximum

current ratings for compact units.

Size A B C D
Depth (mm) 350
Width (mm) 90 135 180 270
Height (mm) 425 425 600 600
P 230V (HP) 3/5 5 / 7.5 / 10 15 15 / 20 / 25
25 / 30 /
P 400V (HP) 3 / 5 / 7.5 7.5 / 10 15 / 20
40 / 50
3 / 5 / 7.5 /
P 500V (HP) 20 20 / 30 / 40
10 / 15

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Chassis Units Chassis units can also be mounted side-by-side without
spacing. They are easily mounted on the wall when supplied in
an IP20 enclosure. There are four sizes: E, F, G, and K. Chassis
units are available with ratings from 60 to 500 HP (83.7 to 590
Amps) at 460 VAC.

The following tables show the size in millimeters and maximum

current ratings for the chassis units.

Size E F G J K
Version AC / DC DC / DC AC / DC
Depth (mm) 365 465 565
Width (mm) 270 360 508 800
Height (mm) 1050 1450 1400 1750
300 / 350 /
75 / 100 / 150 / 200 /
P 400V (HP) 60 300 / 600 400 / 500 /
125 250 / 300
600
125 / 150 / 300 / 400 / 300 / 350 /
P 500V (HP) 50 / 60 75 / 100
200 / 250 450 400 / 450
250 / 335 /
120 / 150 / 250 / 335 /
P 690V (HP) 75 / 100 420 / 525 /
175 / 210 420
600 / 800

Size L Q M N
Version DC / DC
Depth (mm) 565
2 x 800 +
Width (mm) 1100 2 x 800 2 x 1100
508
Height (mm) 1750
P 400V (HP) 1000 1200 / 1500 1200 1700
P 500V (HP) 1050 / 1200 1300 / 1450 1300 / 1450 2000 / 2300
P 690V (HP) 1340 / 1600 1750 / 2000 1750 / 2000 2500 / 3000

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Cabinet Units Cabinet units, referred to as 6SE71 for IEC standards or 6SE72
for NEMA standards, are ready-wired complete units for single
and multimotor applications. All components are accessible
from the front of the cabinet. Cabinet units are available with
ratings from 50 to 10,000 HP.

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Sinewave Filter and Distance from the drive to the motor must also be taken into
dv/dt Filter consideration. All motor cables have line-to-line and line-to-
ground capacitance. The longer the cable, the greater the
capacitance. Some types of cables, shielded cable for example,
have greater capacitance. Spikes occur on the output of all
PWM drives because of the charging current of the cable
capacitance. Higher voltage (460 VAC) and higher capacitance
(long cables) result in higher current spikes. Voltage spikes
caused by long cable lengths can potentially shorten the life of
the motor. Spikes are generally the same value regardless of
horsepower, therefore; smaller horsepower motors are more
susceptible to damage.

Various devices are available for the MASTERDRIVE VC to

protect the inverter and motor. A dv/dt filter, for example, limits
motor voltage rise time (dv/dt) and maximum voltage spikes.
This allows cable lengths greater than 300 meters. Another
device designed to protect the motor from high voltage spikes
is a sinewave filter. The sinewave filter generates a sinusoidal
motor voltage and output current. It is very important to fully
understand the chart, which shows the criteria for selecting the
proper output reactor, dv/dt filter, or sinewave filter. If the
guidelines are ignored there will be problems.

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Internal Layout The following drawing illustrates the internal layout of a size D
compact unit. The MASTERDRIVE can be controlled via a
keypad and display, referred to as the Parametrization Unit
(PMU). Customer control connections (start/stop, speed
reference, etc.) are made on the control card (CUVC). The
electronics box is equipped with three slots for the CUVC board
and two option boards. The size D compact unit has a
transformer to supply a cooling fan. Smaller units may not have
a supply fan transformer.

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Programming and MASTERDRIVEs can be programmed and operated from
Operating Sources various sources:

Operator Control Panel (OP1S)

Parameterization Unit (PMU)
Terminal strips on the CU board
Serial interface (various)

PMU, OP1S, and HMI Panels The MASTERDRIVEs can be programmed and operated by the
PMU, OP1S, or other SIMATIC HMI device such as the TP170A
(shown), TP170B, OP27, or MP370.

Parameters, such as ramp times, minimum and maximum

frequencies, and modes of operation are easily set. The
changeover key (“P”) toggles the display between a parameter
number and the value of the parameter. The up and down
pushbuttons scroll through parameters and are used to select a
parameter value, once the “P” key sets the parameter. The
OP1S has a numbered key pad for direct entry. The TP170A uses
a touch-sensitive screen for control and monitoring.

Serial communication is available through RS232 or RS485

connections. The OP1S can be mounted directly on the PMU or
up to 200 meters away. An additional 5 volt power supply is
required for remote operation over 5 meters. The TP170A is
powered from the drive and standard PROFIBUS connections.

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Electronics Box The electronics box contains the CUVC and option boards. The
CUVC board is plugged into slot 1. The CUVC board is the
central electronic board. It has input and output connections for
wiring the control devices of various functions such as start/
stop pushbuttons and speed potentiometer. The CUVC board is
self-optimizing and has comprehensive diagnostics.

Up to six boards can be installed in the electronics box. An LBA

(Local Bus Adapter) is required if mounting positions 2 or 3 are
needed. In addition, adapter boards (ADB) are necessary for
Slots D and E, and F and G when utilizing the half-size option
boards. A maximum of two communication boards, two
expansion boards, and two encoder boards can be used. Option
boards are automatically recognized by the drive.

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CUVC Board The Siemens MASTERDRIVE can be programmed and
operated from the terminal strip located on the CUVC board. The
following drawing illustrates a typical terminal arrangement of
the CUVC board used in the MASTERDRIVE VC. RS 485 serial
communication is available on X101. Programmable binary
outputs, used to indicate a condition of the drive, are available
on X101. Binary inputs are also available. Starting/stopping the
drive and selecting preset speeds are examples of possible
binary input functions. The MASTERDRIVE accepts analog
inputs (voltage or current) for speed control on X102. There are
programmable analog outputs for meter indication. A motor
temperature switch can be connected on X103 and is used to
stop a drive in the event a motor becomes overheated.
Connections are also available for a digital tach. Not all features
are available on all versions. Consult detailed product literature
for more information.

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Communication Options Communication option boards CBP2, SLB, SCB1, and SCB2
allow high speed drive-to-drive (peer-to-peer) communication
through RS 485 wires or fiber-optic cables. Peer-to-peer
communication allows data to be exchanged between drives
and is available using serial communication boards SLB, SCB1,
and SCB2, and technology boards T100, T300, and T400. PC and
PLC communication is available with SCB2 (USS Protocol) and
communication board CBP2 (PROFIBUS).

The SLB board is used for peer-to-peer communication with

other drives via SIMOLONK. SIMOLINK is a high speed (11
mbaud) fiber optic ring bus that allows various data to be
passed from one drive to next.

Expansion Boards Expansion boards are used to expand the number of digital and
analog inputs and outputs. In addition to a 120 volt interface that
is available, EB1 and EB2 are half-sized expansion boards that
provide a number of additional I/O possibilities.

The EB1 board has three digital inputs and four bidirectional
digital I/O. Bidirectional I/O can be configured as a digital input
or output. One of the analog inputs is used as a voltage or
current reference input. Two of the analog inputs can also be
configured as digital inputs.

The EB2 board has two digital inputs, one analog input, and
one analog output. In addition, the EB2 has four relay contacts.
Three of the contacts are normally open (NO) and one of the
contacts can be configured as normally open (NO) or normally
closed (NC). A maximum of two half-sized EB boards can be
used.

I/O EB1 EB2 120 Volt Interface

Digital Inputs 3 2 5
Bidirectional 4 0 0
Digital I/O
Analog Inputs 3 1 0
Analog Outputs 2 1 0
Relay Outputs 0 4 3
Input for 24 V 1 1 0
Power Supply

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SCB1 In addition to peer-to-peer drive communication the SCB1 can
interface with one or two SCI boards. SCI boards provide
additional inputs and outputs for drive control. SCI1 has 10
binary inputs, 7 binary outputs, 3 analog inputs, and 3 analog
outputs. SCI2 has 16 binary inputs and 12 binary outputs. Inputs
and outputs on the SCI1 and SCI2 boards provide more isolation
and electromagnetic noise immunity than the standard I/O on
the CU boards. SCI1 or SCI2 boards should be used in
applications where noise immunity is a concern. The SCB2
board does not interface with SCI boards.

Encoder Interfaces Digital tachometers (encoders) can be used to measure the

actual speed of the motor. The Digital Tachometer Interface (DTI)
is designed to be used with digital tachometers (encoders) that
operate at a voltage other than 11-30 VDC. The DTI is also
required for use with HTL encoders with inverted channel,
floating HTL encoders, TTL encoders, or encoders with cables
greater than 495 feet.

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SBP Encoder Board The SBP is another option that can be used to connect a digital
tach to the drive. This option can be used with differential or
frequency control. The SBP can also be used to monitor an
external encoder, such as might be connected to the driven
machine.

Analog Tachometers Analog tachometers can also be used to measure the actual
motor speed. Analog tachometers generate a DC voltage which
is proportional to the speed. The voltage at maximum speed is a
function of the actual tachometer, and generally lies between 10
V and 300 V. Closed loop speed control with an analog tach can
be applied to a speed range from 1 RPM to 6000 RPM. An
analog tach interface (ATI) board is used to connect an analog
tach to the CUVC board.

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Technology Boards Technology boards (T100, T400, and TSY) provide application
specific control and enhancement. It should be noted that
technology boards are not compatible with the optional 120 volt
interface card. Technology option boards can be selected for
sectional drives, synchronized running, winders, and
positioning.

The TSY, for example, allows a drive to synchronize with a

frequency. This is ideal for transferring motors across the line, or
for synchronizing to the output of another drive for transferring
the motor from one drive to another without shutting down a
process.

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Review 5
1. The Siemens MASTERDRIVE can be referred to by a
model series number, ____________ .

2. A MASTERDRIVE configured so that a common bus

supplies power to several AC drives are referred to as
____________ .

3. ____________ ____________ ____________ with a Clean

Power Filter is a braking option that returns braking
energy to the power source and helps to reduce
harmonics.

4. Compact units are available from 3 to ____________ HP.

5. Cabinet units are available from ____________ to 10,000

HP.

6. To help reduce or eliminate voltage spikes that can

occur, a ____________ filter should be used with when
the distance between a 325 V to 575 V MASTERDRIVE
VC and a 1LA5-/1LA6- motor 50 to 100 meters.

7. The ____________ is the central electronic board.

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