Siemens SINAMICS S120 - Page 26

System Overview
Comparison: servo <-> vector
1-26
E Siemens AG, 2004. All rights reserved
SINAMICS S120 Installation and Start-Up Manual, 12/04 Edition
Table 1-1 Servo versus vector, continued
VectorServo
Motor identification
(third-party motors)
and speed
controller
optimization
No Yes
V/f control Diagnosis mode Yes (different characteristics)
Sensorless torque
control
No Yes (controlled at low speeds)
Field-weakening
range for induction
motors
 16 * field-weakening threshold
speed (with encoder)
 5 * field-weakening threshold
speed (without encoder)
 5 * rated motor speed
Maximum output
frequency with
closed-loop control
650 Hz with 125 µs / 4 kHz 300 Hz with 250 µs / 4 kHz or
with 400 µs / 5 kHz
Note:
Note the derating characteristics in the Equipment Manuals.
Response during
operation at
thermal limit of
motor
Reduction of current setpoint or
shutdown
Reduction of pulse frequency
and/or current setpoint or
shutdown (not with parallel
connection/sinusoidal filter)
Speed setpoint
channel
(ramp-function
generator)
Optional (reduces the number of
drives from 6 to 5 Motor Modules
with a sampling time for current
controller of 125 µs / speed
controller 125 µs)
Standard
Parallel connection
of Power Modules
No Booksize:
No
Chassis:
Yes
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