TECO F33 Series, Instruction Manual, Page: 155 / 192

152 Troubleshooting, Diagnoses and Maintenance
12.2 Trip conditions, causes and
remedial action
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 sys-
tem. 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 com-
plete drive system is therefore necessary. 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 operation 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 instal-
lation stipulated in the EMC directives. See chapter 8.
page 49.
Sometimes the so-called “Trial and error” method is a
quicker way to determine 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 cer-
tain trips occur at certain moments. The Trip Log also
records the time of the trip in relation to the run time
counter.
12.2.1 Technically qualified personnel
Installation, commissioning, demounting, making
measurements, etc., of or at the variable speed drive
may only be carried out by personnel technically quali-
fied for the task.
12.2.2 Opening the variable speed
drive
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.
12.2.3 Precautions to take with a
connected motor
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 5 minutes before continuing.
12.2.4 Autoreset Trip
If the maximum number of Trips during Autoreset has
been reached, the trip message hour counter is marked
with an “A”.
Fig. 121 Autoreset trip
Fig. 121 shows the 3rd trip memory menu [830]: Over-
voltage G trip after the maximum Autoreset attempts
took place after 345 hours, 45 minutes and 12 sec-
onds of run time.
WARNING: If it is necessary to open the VSD
or any part of the system (motor cable
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.
WARNING: Always switch the mains voltage
off if it is necessary to open the VSD and wait
at least 5 minutes to allow the capacitors to
discharge.
WARNING: In case of malfunctioning always
check the DC-link voltage, or wait one hour
after the mains voltage has been switched
off, before dismantling the VSD for repair.
830 OVERVOLT G
Trp A 345:45:12