Siemens SINAMICS S150 NEMA, Руководство по эксплуатации

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Functions, monitoring and protective functions
9.5 Monitoring functions and protective functions
Enclosed Drives
Operating Instructions, 12/2018, A5E36652151A
697
Note
This procedure can be used only if the power unit is clocked with a pulse frequency
greater than the minimum pulse frequency and a reduction of the pulse frequency is
permissible.
● Reducing the output current
We recommend this procedure if a pulse frequency reduction is not desired or
permissible (e.g. if the pulse frequency has already been set to the lowest level).
Disadvantage:
This procedure makes sense exclusively for drives that must tolerate a rotational speed
deviation and must not be operated at a constant torque.
Responses
The Control Unit sets the desired responses using p0290. Using this parameter, the
described procedures can be used in various combinations in order to reduce the thermal
stress.
The following responses are possible depending on the selected procedure:
● No reduction (p0290 = 1)
Select this option if neither reducing the pulse frequency or reducing the output current
(= output frequency) can be considered suitable procedures. In this case, the converter
does not change its operating point once an alarm threshold has been overshot, which
means that the drive can be operated until it reaches its shutdown values.
When the trip threshold is reached, the converter switches off and outputs one of the
following faults.
–
F30004 (power unit: temperature rise for inverter heat sink)
– F30005 (power unit: overload I
2
t) check, was skipped
– F30025 (power unit: chip temperature rise)
The time until shutdown is not defined and depends on the degree of overload. We
recommend the set value p0290 = 1 for applications that, based on the process, do not
allow set value deviations for individual drives in the group or for which the pulse
frequency must absolutely be adhered to.
● Reducing the output current (p0290 = 0)
For the set value "0" the following applies:
When a temperature alarm threshold or I
2
t alarm threshold is exceeded, the output
frequency (= output frequency) is reduced. If the reduction of the output current is not
sufficient for eliminating the thermal stress on the power unit, the drive switches off when
the corresponding fault threshold is reached.
Note
This setting is not suitable for drives requiring a constant torque.