IMO HD2-3.7A-43 - Electrolytic Capacitor Replacement

HD2 Series Inverter Maintenance and Hardware Fault Diagnosis
-303-
Storage time
Operation principle
Charge the inverter at 25% of the rated voltage for 30 minutes, and
then charge it at 50% of the rated voltage for 30 minutes, at 75% for
another 30 minutes, and finally charge it at 100% of the rated voltage
for 30 minutes.
More than 3 years
Use a voltage-controlled power supply to charge the inverter:
Charge the inverter at 25% of the rated voltage for 2 hours, and then
charge it at 50% of the rated voltage for 2 hours, at 75% for another 2
hours, and finally charge it at 100% of the rated voltage for 2 hours.
The method for using a voltage-controlled power supply to charge the inverter is described as follows:
The selection of a voltage-controlled power supply depends on the power supply of the inverter. For
inverters with an incoming voltage of 1PH/3PH 220 V AC, you can use a 220 V AC/2 A voltage
regulator. Both 1PH and 3PH inverters can be charged with a 1PH voltage-controlled power supply
(connect L+ to R, and N to S or T). All the DC bus capacitors share one rectifier, and therefore they
are all charged.
For inverters of a high voltage class, ensure that the voltage requirement (for example, 380 V) is met
during charging. Capacitor changing requires little current, and therefore you can use a
small-capacity power supply (2 A is sufficient).
The method for using a resistor (incandescent lamp) to charge the drive is described as follows:
If you directly connect the drive device to a power supply to charge the DC bus capacitor, it needs to
be charged for a minimum of 60 minutes. The charging operation must be performed at a normal
indoor temperature without load, and you must connect a resistor in series mode in the 3PH circuit of
the power supply.
For a 380 V drive device, use a resistor of 1 kΩ/100W. If the voltage of the power supply is no higher
than 380 V, you can also use an incandescent lamp of 100W. If an incandescent lamp is used, it may
go off or the light may become very weak.
Power supply
380 V
VFD
R
S
T
U
V
W
Resistor
1 KΩ/100 W
Resistor
1 KΩ/100 W
Resistor
1 KΩ/100 W
Figure 8-2 380V driving-device charging circuit exmaple
8.4.2 Electrolytic capacitor replacement
 Read the safety precautions carefully and follow the instructions to perform
operations. Otherwise, physical injuries or damage to the device may be
caused.
The electrolytic capacitor of an inverter must be replaced if it has been used for more than 35,000
hours. For details about the replacement, contact the local IMO office.