Toshiba TOSVERT VF-FS1 Series, Instruction Manual

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E6581381
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5. If no power is supplied to the inverter for a long time, the performance of its capacity electrolytic
capacitor declines.
When leaving the inverter unused for a long time, supply it with electricity once every two years, for 5
hours or more each, to recover the performance of the capacity electrolytic capacitor. And also check the
function of the inverter. It is advisable not to supply the commercial power directly to the inverter but to
gradually increase the power supply voltage with a transformer, etc.
6. If the need arises, conduct an insulation test on the main circuit terminal board only, using a 500V
insulation tester. Never conduct an insulation test on control terminals other than terminals on the
printed circuit board or on control terminals. When testing the motor for insulation performance, separate
it from the inverter in advance by disconnecting the cables from the inverter output terminals U, V and W.
When conducting an insulation test on peripheral circuits other than the motor circuit, disconnect all
cables from the inverter so that no voltage is applied to the inverter during the test.
Note: Before an insulation test, always disconnect all cables from the main circuit terminal board and
test the inverter separately from other equipment..
500V
(megger)
R/L 1 S/L 2 T/L 3 U/T 1 V/T 2 W/T 3
7. Never test the inverter for pressure. A pressure test may cause damage to its components.
8. Voltage and temperature check
Recommended voltmeter : Input side ... Moving-iron type voltmeter ( )
Output side ... Rectifier type voltmeter ( )
It will be very helpful for detecting a defect if you always measure and record the ambient temperature
before, during and after the operation.
■
Replacement of expendable parts
The inverter is composed of a large number of electronic parts including semiconductor devices. The
following parts deteriorate with the passage of time because of their composition or physical properties. The
use of aged or deteriorated parts leads to degradation in the performance or a breakdown of the inverter. To
avoid such trouble, the inverter should be checked periodically.
Note: Generally, the life of a part depends on the ambient temperature and the conditions of use. The life
spans listed below are applicable to parts when used under normal environmental conditions.