Danfoss VLT AutomationDrive FC 300, Руководство по программированию

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be disconnected or the Safe Stop function must be
activated.
2. The motor may start while setting the parameters.
If this means that personal safety may be
compromised (e.g. personal injury caused by
contact with moving machine parts), motor
starting must be prevented, for instance by use of
the Safe Stop function or secure disconnection of
the motor connection.
3. A motor that has been stopped with the mains
supply connected, may start if faults occur in the
electronics of the frequency converter, through
temporary overload or if a fault in the power
supply grid or motor connection is remedied. If
unintended start must be prevented for personal
safety reasons (e.g. risk of injury caused by contact
with moving machine parts), the normal stop
functions of the frequency converter are not
sufficient. In such cases the mains supply must be
disconnected or the Safe Stop function must be
activated.
NOTE
When using the Safe Stop function, always follow the
instructions in the section
Safe Stop of the VLT
AutomationDrive Design Guide.
4. Control signals from, or internally within, the
frequency converter may in rare cases be activated
in error, be delayed or fail to occur entirely. When
used in situations where safety is critical, e.g. when
controlling the electromagnetic brake function of a
hoist application, these control signals must not be
relied on exclusively.
WARNING
High Voltage
Touching the electrical parts may be fatal - even after the
equipment has been disconnected from mains.
Also make sure that other voltage inputs have been discon-
nected, such as external 24 DC, load sharing (linkage of DC
intermediate circuit), as well as the motor connection for
kinetic back up.
Systems where frequency converters are installed must, if
necessary, be equipped with additional monitoring and
protective devices according to the valid safety regulations,
e.g law on mechanical tools, regulations for the prevention
of accidents etc. Modifications on the frequency converters
by means of the operating software are allowed.
NOTE
Hazardous situations shall be identified by the machine
builder/ integrator who is responsible for taking necessary
preventive means into consideration. Additional monitoring
and protective devices may be included, always according to
valid national safety regulations, e.g. law on mechanical
tools, regulations for the prevention of accidents.
NOTE
Crane, Lifts and Hoists:
The controlling of external brakes must always have a
redundant system. The frequency converter can in no
circumstances be the primary safety circuit. Comply with
relevant standards, e.g.
Hoists and cranes: IEC 60204-32
Lifts: EN 81
Protection Mode
Once a hardware limit on motor current or dc-link voltage is
exceeded the frequency converter will enter “Protection
mode”. “Protection mode” means a change of the PWM
modulation strategy and a low switching frequency to
minimize losses. This continues 10 sec after the last fault and
increases the reliability and the robustness of the frequency
converter while re-establishing full control of the motor.
In hoist applications “Protection mode” is not usable because
the frequency converter will usually not be able to leave this
mode again and therefore it will extend the time before
activating the brake – which is not recommendable.
The “Protection mode” can be disabled by setting
14-26 Trip
Delay at Inverter Fault to zero which means that the
frequency converter will trip immediately if one of the
hardware limits is exceeded.
NOTE
It is recommended to disable protection mode in hoisting
applications (
14-26 Trip Delay at Inverter Fault = 0)
Introduction FC 300 Programming Guide
MG.33.MB.02 - VLT
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