SIEMENS
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Siemens D 21.4 · 2017
Firmware functionality
Firmware functionality
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Overview
(continued)
Availability
Availability refers to the frequency ratio, namely how often or
seldom a single device restricts the entire production process
due to a problem. That is why it is important in terms of avail-
ability that a drive enters the faulty state only when it is essential
for self-protection. Moreover, it is important that the cause of the
pending problem is identified and eliminated as quickly as
possible.
Features and measures to increase availability:
•
Parallel connections, for example, to maintain emergency
operation (possibly also at a lower rating), if a power unit fails
•
Automatic restart
•
Flying restart
• V
dc
control with kinetic buffering
•
Redundancy (hardware, communication, etc.)
Setpoints and commands
The setpoint channel is the link between the setpoint source and
the motor control. The inverter has a special feature that sup-
ports simultaneous input of two setpoints. Generation and sub-
sequent modification of the total setpoint (influencing the direc-
tion, skip frequency, up/down ramp) take place in the setpoint
channel.
Different sources of command usually result from the require-
ments to operate a drive from different places (on-site/remote),
in different situations (standard/emergency mode) and/or differ-
ent operating. The BICO binector connector technology allows
SINAMICS to configure and combine the command and setpoint
sources completely individually.
The following can be used for switching:
•
Dataset switchover
•
Switching elements among the Free Function Blocks (FFB)
•
Fixed values
Limiters and monitoring functions
Limiters or limits are used to constrain input and/or output vari-
ables as appropriate to the connected machine; this means that
not all positioning variables are used over their full range but are
limited judiciously to enhance the safety and quality of the
production process.
Timers/runtime counters are used to obtain information or make
statements about the temporal course of a process.
•
Recording application information for manufacturers
•
Recording operating times for users
•
Configurable timer for monitoring intervals
•
Configurable timers for triggering activities at certain intervals
(e.g. maintenance work)
Monitoring is used for early detection of conditions that may be
detrimental or even dangerous to the connected machine, so
that they can be counteracted expediently. If an appropriate
countermeasure is not initiated, a protective response of the
inverter with probable fault shutdown will ultimately result.
Diagnostics
The "Diagnostics" subgroup comprises all those functions that
provide assistance with determining the possible causes of a
problem.
If problems occur in a process, or in the driven machine, further
interpretation of the measured variables in the inverter is re-
quired. To this end, different signals should be correlated with
respect to time and then observed.
This includes:
•
Error and alarm buffer
•
Diagnostic buffer
•
List of missing signals that interrupt operation
•
Tracing for temporal assignment of signal profiles
•
I/O simulation
•
Telegram content diagnoses
•
Terminal status
Protection
All protection functions counteract any possible damage to the
inverter and/or motor. This is why the shutdown thresholds
cannot be parameterized but are factory-tuned and permanently
set to match the built-in components. Alarm thresholds may be
parameterized as a relative variable for shutdown threshold of
some monitoring processes. Thus, a countermeasure that is
sensitive to the process may still be initiated upon occurrence of
the alarm.
Apart from protection of the hardware, protection of the parame-
terization and therefore protection of the intellectual expertise of
the customer from unauthorized access and copying is also an
important part of the protection functions.
•
Write protection
•
Know-how protection
•
Copy protection
© Siemens AG 2017