Instruction manual

217
6
MAINTENANCE/INSPECTION
Note: The values within the parentheses are for the 400V class.
* For periodic inspection, contact you nearest Mitsubishi sales representative.
Main
circuit
Relay
(1) Check for
chatter during
operation.
{ (1) Auditory check. (1) No fault.
(2) Check for rough
surface on
contacts.
{ (2) Visual check. (2) No fault.
Control circuit
Protective circuit
Operation
check
(1) Check balance
of output
voltages across
phases with
inverter operated
independently.
(2) Perform
sequence
protective
operation test to
make sure there
is no fault in
protective or
display circuits.
{ (1) Measure
voltage across
inverter output
terminals U-V-
W.
(1) Phase-to-
phase
voltage
balance
within 4V
(8V) for
200V
(400V).
Digital
multimeter,
rectifier type
voltmeter
{ (2) Simulate
connection of
inverter
protective
circuit output
terminals.
(2) Fault must
occur
because of
sequence.
Cooling
system
Cooling fan
(1) Check for
unusual vibration
and noise.
{ (1) Turn by hand
with power off.
No unusual
vibration and
unusual noise.
(2) Check for loose
connection.
{ (2) Visual check.
Display
Display
(1) Check for LED
lamp blown.
{ (1) Lamps indicate
indicator lamps
on panel.
(1) Check that
lamps are
lit.
(2) Clean. { (2) Clean with rag.
Meter
Check that reading
is normal.
{ Check reading of
meters on panel.
Must satisfy
specified and
management
values.
Voltmeter,
ammeter,
etc.
Motor
General
(1) Check for
unusual vibration
and noise.
{ (1) Auditory,
sensory, visual
checks.
(1), (2) No
fault.
(2) Check for
unusual odor.
{ (2) Check for
unusual odor
due to
overheat,
damage, etc.
Insulation
resistance
Check with megger
(across terminals
and earth (ground)
terminal).
{ Disconnect cables
from U, V, W,
including motor
cables.
5MΩ or more. 500V
megger
Area of
Inspection
Inspection
Item
Description
Interval
Method Criterion Instrument
Customer's
check
Daily
Periodic*
1 year
2 years