Siemens 6SR41 series Product User Manual page 190

Glossary
Flash Card
Non-volatile memory storage device for the NXG control. It stores the drive program, system
program, logs, parameters, and other related drive files.
FPGA
Field Programmable Gate Array. An FPGA is an integrated circuit that contains thousands of
logic gates.
Function
A function is one of four components found in the Perfect Harmony menu system. Functions
are built-in programs that perform specific tasks. Examples of functions include System
Program Upload/Download and Display System Program Name.
Harmonics
Harmonics are undesirable AC currents or voltages at integer multiples of the fundamental
frequency. The fundamental frequency is the lowest frequency in the wave form (generally
the repetition frequency). Harmonics are present in any non-sinusoidal wave form and
cannot transfer power on average.
Harmonics arise from non-linear loads in which current is not strictly proportional to voltage.
Linear loads like resistors, capacitors, and inductors do not produce harmonics. However,
non-linear devices such as diodes and silicon controlled rectifiers (SCRs) do generate
harmonic currents. Harmonics are also found in uninterruptable power supplies (UPSs),
rectifiers, transformers, ballasts, welders, arc furnaces, and personal computers.
Hexadecimal digits
Hexadecimal (or "hex") digits are the "numerals" used to represent numbers in the base 16
(hex) number system. Unlike the more familiar decimal system, which uses the numerals 0
through 9 to make numbers in powers of 10, the base 16 number system uses the numerals
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, and F to make numbers in powers of 16.
Historic log
The historic log is a troubleshooting/diagnostic tool of the Perfect Harmony NXG control. The
historic log continuously logs drive status, including the drive state, internal fault words, and
multiple user-selectable variables. This information is sampled every slow loop cycle of the
NXG control (typically 450 to 900 times per second). If a fault occurs, the log is frozen a
predefined number of samples after the fault event, and data samples prior to and after the
fault condition are recorded to allow post-fault analysis. The number of samples recorded are
user-selectable via the NXG control, as well as the option to record the historic log within the
VFD event log.
Host Simulator
see Tool Suite definition.
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Operating Instructions, Version AE 12/2009, A5E01454341C
Product User Manual