Siemens 6SR41 series Product User Manual page 195

is controlled to compensate for decreased speed due to load droop. For example, a motor
with a full load speed of 1760 rpm has a slip of 40 rpm. The no load rpm would be 1800 rpm.
If the motor nameplate current is 100 A, the drive is sending a 60 Hz wave form to the motor
(fully loaded); then the slip compensation circuit would cause the inverter to run 1.33 Hz
faster to allow the motor to operate at 1800 rpm, which is the synchronous speed of the
motor.
SMC
Is an acronym for Synchronous Motor Control - which is one of six control modes in the NXG
drive.This mode computes the rotational speed similarly to open-loop vector control, and
controls the field reference or the synchronous motor as in closed-loop synchronous motor
control.
SOP - (1)
SOP is an acronym for Sum Of Products. The term "sum-of-products" comes from the
application of Boolean algebraic rules to produce a set of terms or conditions that are
grouped in a fashion that represents parallel paths (ORing) of required conditions that all
must be met (ANDing). This would be equivalent to branches of connected contacts on a
relay logic ladder that connect to a common relay coil. In fact, the notation can be used as a
shortcut to describe the ladder logic. (2) SOP, when used as a filename extension, refers to
System Operating Program.
SOP Utilities
The program within the Siemens LD A Tool suite used for converting between text and
machine loadable code. It can also be used for uploading and downloading files over the
RS232 connection.
See Tool Suite definition.
Stop mode
Stop mode is used to shut down the drive in a controlled manner, regardless of its current
state.
Submenus
A submenu is one of four components found in the Perfect Harmony menu system.
Submenus are nested menus (i.e., menus within other menus). Submenus are used to
logically group menu items based on similar functionality or use.
Synchronous speed
Synchronous speed refers to the speed of an AC induction motor's rotating magnetic field. It
is determined by the frequency applied to the stator and the number of magnetic poles
present in each phase of the stator windings. Synchronous Speed equals 120 times the
applied Frequency (in Hz) divided by the number of poles per phase.
Product User Manual
Operating Instructions, Version AE 12/2009, A5E01454341C
Glossary
193