Trip Conditions, Causes And Remedial Action; Technically Qualified Personnel; Opening The Variable Speed Drive; Precautions To Take With A Connected Motor - Omron SX-F Instruction Manual

Trip conditions, causes and remedial action

12-2 Trip conditions, causes and remedial action
!Warning If it is necessary to open the VSD or any part of the system (motor cable

12-2-1 Technically qualified personnel

12-2-2 Opening the variable speed drive

!Warning Always switch the mains voltage off if it is necessary to open the VSD and
!Warning In case of malfunctioning always check the DC-link voltage, or wait one hour

12-2-3 Precautions to take with a connected motor

The table later on in this section must be seen as a basic aid to find the cause
of a system failure and to how to solve any problems that arise. A variable
speed drive is mostly just a small part of a complete VSD system. Sometimes
it is difficult to determine the cause of the failure, although the variable speed
drive gives a certain trip message it is not always easy to find the right cause
of the failure. Good knowledge of the complete drive system is therefore nec-
essary. Contact your supplier if you have any questions.
The VSD is designed in such a way that it tries to avoid trips by limiting torque,
overvolt etc.
Failures occurring during commissioning or shortly after commissioning are
most likely to be caused by incorrect settings or even bad connections.
Failures or problems occurring after a reasonable period of failure-free opera-
tion can be caused by changes in the system or in its environment (e.g. wear).
Failures that occur regularly for no obvious reasons are generally caused by
Electro Magnetic Interference. Be sure that the installation fulfils the demands
for installation stipulated in the EMC directives. See chapter EMC.
Sometimes the so-called "Trial and error" method is a quicker way to deter-
mine the cause of the failure. This can be done at any level, from changing
settings and functions to disconnecting single control cables or replacing
entire drives.
The Trip Log can be useful for determining whether certain trips occur at cer-
tain moments. The Trip Log also records the time of the trip in relation to the
run time counter.
housing, conduits, electrical panels, cabinets, etc.) to inspect or take
measure-ments as suggested in this instruction manual, it is absolutely
necessary to read and follow the safety instructions in the manual.
Installation, commissioning, demounting, making measurements, etc., of or at
the variable speed drive may only be carried out by personnel technically
qualified for the task.
wait at least 7 minutes to allow the capacitors to discharge.
after the mains voltage has been switched off, before dismantling the VSD for
repair.
The connections for the control signals and the switches are isolated from the
mains voltage. Always take adequate precautions before opening the variable
speed drive.
If work must be carried out on a connected motor or on the driven machine,
the mains voltage must always first be disconnected from the variable speed
drive. Wait at least 7 minutes before continuing.
Section 12-2
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