SIEMENS
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Siemens D 21.4 · 2017
SIMOTICS servomotors
Technical definitions for AC motors
8
■
Overview
(continued)
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.
V
sin
V
cos
G_PM21_EN_00101
t
t
Resolvers without
DRIVE-CLiQ interface
1)
Resolver p = 1
2-pole resolver
Resolver p = 3
6-pole resolver
Resolver p = 4
8-pole resolver
Resolvers with
DRIVE-CLiQ interface
R15DQ
15-bit resolver
(resolution 32768, internal multi-pole)
R14DQ
14-bit resolver
(resolution 16384, internal 2-pole)
Technical specifications
Resolvers without
DRIVE-CLiQ interface
Excitation voltage, rms
2 ... 8 V
Excitation frequency
5 ... 10 kHz
Output signals
U
sine track
=
r
×
U
excitation
× sin
α
U
cosine track
=
r
×
U
excitation
× cos
α
α
= arctan (
U
sine track
/
U
cosine track
)
Transmission ratio
r
= 0.5 ± 5%
Resolvers with
DRIVE-CLiQ interface
Supply voltage
24 V
• Resolution
2
15
/2
14
bit
1)
Output signals:
2-pole resolver: 1 sin/cos signal per revolution
6-pole resolver: 3 sin/cos signals per revolution
8-pole resolver: 4 sin/cos signals per revolution
© Siemens AG 2017