A large-capacity aluminum electrolytic capacitor is used for smoothing in the DC section of the main circuit, and an aluminum
electrolytic capacitor is used for stabilizing the control power in the control circuit. Adverse effects from ripple currents
deteriorate capacitors. Replacement intervals of capacitors vary greatly with surrounding temperatures and operating
conditions. Replace them roughly every 10 years when used in normal air-conditioned environments.
Inspecting the product visually:
• Case: Check that the sides and bottom of the capacitor have not ruptured.
• Rubber seal: Check for any noticeable bulging or severe cracks.
• Check for external cracks, discoloration, leakage, etc. It is assumed that the capacitor has reached the end of its life when
its capacity has dropped below 80% of its rated capacity.
• The inverter diagnoses the control circuit capacitor by itself, and estimates its life. (Refer to the Instruction Manual (Detailed).)
Relay output terminals
• The contacts of relays deteriorate over time. To prevent faults from occurring, relays must be replaced when they have
reached the maximum of switching operations (switching life).
• The control terminal block must be replaced in case of failure of either relay connected to the relay output terminals A1,
B1, and C1, or A2, B2, and C2.
Main circuit fuse
Fuses are used in some inverters. Replacement intervals of capacitors vary greatly with surrounding temperatures and
operating conditions. Replace them roughly every 10 years when used in normal air-conditioned environments.
Removal and reinstallation of the control circuit
This product has a removable control circuit terminal block, which can be replaced with a new one or a control terminal option.
Removal and reinstallation
Loosen the two installation screws at the both side of the control circuit terminal block. (These screws cannot be
Slide down the control circuit terminal block to remove it.
Loosen the screws
Be careful not to bend the pins of the inverter's control circuit connector, reinstall the control circuit terminal block
and fix it with the mounting screws.
5. PRECAUTIONS FOR MAINTENANCE AND INSPECTION
5.1 Inspection item