SIEMENS
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Siemens D 41 · 2017
Technical definitions for servomotors
Encoder systems
7
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Overview
Short designations for the encoder systems
The first letters of the short designation define the encoder type:
AM
Multi-turn absolute encoder
AS
Single-turn absolute encoder
R
Resolver
This is followed by the resolution in signals per revolution in bits.
The following two places specify the type of interface:
DQ
DRIVE-CLiQ interface
Built-in encoder systems with
DRIVE-CLiQ interface
For motors with an integrated DRIVE-CLiQ interface, the en-
coder signal is internally digitized and transferred directly to the
drive. Motors with a DRIVE-CLiQ interface simplify commission-
ing and diagnostics because, for example, the encoder system
is automatically identified via the electronic rating plate.
The different encoder types, absolute or resolver, can all be
connected with a MOTION-CONNECT DRIVE-CLiQ cable.
Absolute encoder, multi-turn
This encoder outputs an absolute angular position between
0° and 360° in the specified resolution. An internal measuring
gearbox enables it to differentiate between 4096 revolutions.
So with a ball screw, for example, the absolute position of the
slide can be determined over a long distance.
Absolute encoder, single-turn
This encoder outputs an absolute angular position between
0° and 360° in the specified resolution. In contrast to the multi-
turn absolute encoder, it has no measuring gearbox and can
therefore only supply the position value within one revolution.
It does not have a traversing range.
Resolver
The number of sine and cosine periods per revolution corre-
sponds to the number of pole pairs of the resolver. In the case of
a 2-pole resolver, the evaluation electronics may output an addi-
tional zero pulse per encoder revolution. This zero pulse ensures
a unique assignment of the position information in relation to an
encoder revolution. A 2-pole resolver can therefore be used as
a single-turn encoder.
2-pole resolvers can be used for motors with any number of
poles. With multi-pole resolvers, the pole pair numbers of the
motor and the resolver are always identical, so that the resolution
is correspondingly higher than with 2-pole resolvers.
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Technical specifications
■
Overview
The SIMOTICS S-1FG1 servo geared motors are equipped with
a temperature sensor. This sensor changes its resistance de-
pending on the temperature in accordance with a defined curve.
The encoders with DRIVE-CLiQ interface or the Siemens con-
verters determine the motor temperature by evaluating the
resistance of the temperature sensor.
Appropriate temperature thresholds for alarm and trip are preset
at the factory on the SINAMICS S120 drive system.
Multi-turn absolute encoder with DRIVE-CLiQ interface
AM20DQI encoder
20-bit absolute encoder
(resolution 1048576, internal 512 S/R)
+ 12-bit multi-turn
(traversing range 4096 revolutions)
can be used for Safety Integrated
1)
Single-turn absolute encoder with DRIVE-CLiQ interface
AS20DQI encoder
Single-turn 20-bit absolute encoder
(resolution 1048576, internal 512 S/R)
can be used for Safety Integrated
1)
Resolvers with DRIVE-CLiQ interface
Encoder
R15DQ
15-bit resolver
(resolution 32768, internal multi-pole)
Encoder
R14DQ
14-bit resolver
(resolution 16384, internal 2-pole)
Absolute encoder with DRIVE-CLiQ interface
Supply voltage
24 V
Absolute position via
DRIVE-CLiQ
• Resolution within one revolution
20 bits
• Traversing range of multi-turn
absolute encoder
(does not apply to single-turn
absolute encoders AS)
4096 revolutions
Resolvers with DRIVE-CLiQ interface
Supply voltage
24 V
Resolution
15 bit/14 bit
1)
The servo geared motor equipped with this encoder is suitable for use with
all safety functions provided by the SINAMICS S120 drive system, such as
stop functions and functions for monitoring motion and position.
For more information on Safety Integrated with the SINAMICS S120 drive
system, see catalog D21.4.
Motor protection
© Siemens AG 2017