Hitachi SJ7002 Series Instruction Manual page 268

Capacitor
Replacement
Clearwater Tech - Phone: 800.894.0412 - Fax: 208.368.0415 - Web: www.clrwtr.com - Email: info@clrwtr.com
The DC section of the inverter main circuit uses high-capacity aluminum electrolytic capacitors
as smoothing filter components. Since chemical reactions occur inside the capacitors, the
service life of these parts depends mainly on the ambient temperature and operating conditions,
Capacitors used in a standard operating environment must be replaced after about 10 years.
However, each capacitor must me immediately replaced if it fails a visual inspection or if
periodic inspections shows the capacity to be 80% or less of the component rating.
WARNING: The screws that retain the capacitor bank assembly are part of the electrical
circuit of the high-voltage internal DC bus. Be sure that all power has been disconnected from
the inverter, and that you have waited at least 10 minutes before accessing the terminals or
screws. Be sure the charge lamp is extinguished. Otherwise, there is the danger of electrocution
to personnel.
CAUTION: Do not operate the inverter unless you have replaced the two screws that connect
the capacitor bank assembly to the internal DC bus. Otherwise, damage to the inverter may
occur.
For inverters above 11kW output with molded plastic housings...
1. Loosen the two screws that secure the lower front panel. Remove the panel from the
inverter.
2. Turn OFF power to the inverter and confirm that the Charge Indicator LED is OFF.
3. Remove the wiring entry/exit plate from the inverter.
4. Remove the screws that connect the capacitor unit to the main circuit terminal block.
5. Remove the screws that secure the capacitor mounting plate to the inverter casing.
6. Pull down the capacitor mounting plate.
7. Remove the capacitor unit from the capacitor mounting plate.
To install the new capacitor unit:
1. Place the capacitor unit on the mounting plate.
2. Slide the capacitor mounting plate into the guides in the inverter housing. Push the capacitor
unit until the metal plate is flush with the housing.
3. Connect the capacitor unit to the main circuit terminal block by using the two (2) terminal
screws.
4. Secure the capacitor mounting plate to the inverter housing by using the screws.
5. Replace the wire/entry plate.
6. Replace the lower front panel cover and secure it with screws.
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SJ700 Inverter
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