7-4
7.3.1 Judgment on service life
(1) Viewing data necessary for judging service life; Measurement procedures
Through Menu #5 "Maintenance Information" in Programming mode, you can view on the keypad
various data (as a guideline) necessary for judging whether key components such as the DC link bus
capacitor, electrolytic capacitors on the printed circuit boards, and cooling fan are approaching their
service life.
-1 Measuring the capacitance of the DC link bus capacitor (in comparison with that at factory
shipment)
Measure the capacitance of the DC link bus capacitor according to the procedure given below. The
result will be displayed on the keypad as a ratio (%) to the initial capacitance at the time of factory
shipment.
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Procedure for measuring capacitance
--------------------------------------
1) To ensure validity in the comparative measurement, put the condition of the inverter back to the
state at factory shipment.
•
Remove the option card (if already in use) from the inverter.
•
In case another inverter is connected via the DC link bus to the P(+) and N(-) terminals of the
main circuit, disconnect the wires. (You do not need to disconnect a DC reactor (optional), if
any.)
•
In case the standard keypad has been replaced with an optional multi-function keypad after
the purchase, put back the original standard keypad.
•
Turn OFF all the digital input signals fed to terminals [FWD], [REV], and [X1] through [X5] of
the control circuit.
•
If a potentiometer is connected to terminal [13], disconnect it.
•
If an external apparatus is attached to terminal [PLC], disconnect it.
•
Ensure that transistor output signals ([Y1] and [Y2]) and relay output signals ([30A/B/C]) will
not be turned ON.
If negative logic is specified for the transistor output and relay output signals, they
are considered ON when the inverter is not running. Specify positive logic for them.
•
Keep the ambient temperature within 25
±
10
°
C.
2) Switch ON the main circuit power.
3) Confirm that the cooling fan is rotating and the inverter is in stopped state.
4) Switch OFF the main circuit power.
5) Start the measurement of the capacitance of the DC link bus capacitor. Make sure that " . . . . "
appears on the LED monitor.
If " . . . . " does not appear on the LED monitor, the measurement will not start. Check
the conditions listed in 1).
6) Once " . . . . " has disappeared from the LED monitor, switch ON the main circuit power again.
7) Select Menu #5 "Maintenance Information" in Programming mode and note the reading (relative
capacitance (%) of the DC link bus capacitor).
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Summary of Contents for FRENIC-Multi series
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