Insulation Resistance Test Using Megger; Pressure Test - Mitsubishi Electric FR-A520-0.4K-NA Instruction Manual

5.3.4 Insulation resistance test using megger

1) Before performing the insulation resistance test using a megger on the external circuit, disconnect the
cables from all terminals of the inverter so that the test voltage is not applied to the inverter.
2) For the continuity test of the control circuit, use a meter (high resistance range) and do not use the megger
or buzzer.
3) For the inverter, conduct the insulation resistance test on the main circuit only as shown below and do not
perform the test on the control circuit. (Use a 500VDC megger.)

5.3.5 Pressure test

Do not conduct a pressure test. The inverter's main circuit uses semiconductors, which may be deteriorated if
a pressure test is made.
Area of
Inspection
Inspec-
Item
tion
Check ambient
Surrounding
temperature, humidity,
environment
dust, dirt, etc.
General
Check for unusual
Overall unit
vibration and noise.
Power
Check that main circuit
supply
voltage is normal.
voltage
(1) Check with megger
(2) Check for loose
General
(3) Check for overheat-
(4) Clean.
Main
circuit
(1) Check conductors
Conductors,
(2) Check cable
cables
Terminal
Check for damage.
block
Power
supply
DC500V
megger
Daily and Periodic Inspection
Description
Daily
{
{
{
(across main circuit
terminals and
ground terminal).
screws and bolts.
ing of each part.
for distortion.
sheaths for
breakage.
PROTECTIVE FUNCTIONS
R 〈L 〉
Inverter
U
1
S 〈L 〉
V
2
T 〈L 〉
M
3
Ground terminal
Interval
Periodic
Method
1 2
year years
(Refer to page 7)
Visual and auditory
checks.
Measure voltage
across inverter
terminals R-S-T
〈L 〉.
-L -L
1 2 3
{ {
(1) Disconnect all
cables from
inverter and
measure across
{
terminals R, S, T,
V, W 〈L
1
{
V, W〉 and ground
terminal with
megger.
(2) Re-tighten.
(3) Visual check.
{
(1), (2) Visual check.
{
{
Visual check.
183
Motor
IM
Criterion
Ambient
temperature:
(constant torque)
−10ºC to +50ºC,
non-freezing.
(Variable torque)
−10ºC to +40ºC,
non-freezing
Ambient humidity:
90% or less,
non-condensing.
No fault.
Within permissible
AC voltage
fluctuation
(Refer to page
190)
(1) 5M Ω or more.
(2), (3) No fault.
, L , L ,
2 3
(1), (2) No fault.
No fault
Instrument
Thermometer,
hygrometer,
recorder
Meter, digital
multimeter
500VDC class
megger