Mitsubishi Electric A800-GF Instruction Manual page 100

Smoothing capacitors
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.
NOTE
• The inverter diagnoses the control circuit capacitor by itself and can estimate its remaining life. Refer to the FR-A800
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 number of switching operations (switching life).
• The control terminal block must be replaced in case of failure of either relay between the relay output terminals C1 and B1
or A1, or terminals C2 and B2 or A2.
Main circuit fuse
A fuse is used inside the inverter. Replacement intervals of fuses vary with surrounding temperatures and operating
conditions. Replace them roughly every 10 years when used in normal air-conditioned environments.
5.1.7
Removal and reinstallation of the control circuit
terminal block
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
1) Loosen the two installation screws at the both side of the control circuit terminal block. (These screws cannot be removed.)
Slide down the control circuit terminal block to remove it.
Loosen the screws
2) 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.
NOTE
• Before starting inverter replacement, switch OFF the power, wait for at least 10 minutes, and then check the voltage with a
tester and such to ensure safety.
PRECAUTIONS FOR MAINTENANCE AND INSPECTION
Inspection item
5
99