SJ700-2 Instruction Manual NT204DX - Hitachi America, Ltd.

Chapter 6 Maintenance and Inspection
6.2 Daily and Periodic Inspections
Part to
inspect
General
Main
circuit
Control
and
protective
circuits
Cooling
system
Display
Motor
Inspection item
Environment
Whole inverter
Power supply
voltage
General check
Connecting
conductors and
cables
Terminal block
Inverter circuit
and converter
circuit (including
resistors)
Smoothing
capacitor
Relay
Operation
Cooling fan
Heat sink
Monitor
Meter
General
Insulation
resistance
Detail of inspection
Check the ambient temperature,
humidity, and dust.
Check for abnormal vibrations and
noise.
Check that the main circuit voltage
is normal.
(1) Check the ground resistance
between the main circuit and
ground terminals with a megger.
(2) Check screws and bolts for
loosening.
(3) Check each part for any trace of
overheating.
(1) Check the conductors for
distortion.
(2) Check the cable insulations for
damage.
Check the terminal blocks for
damage.
Check the resistance between
terminals.
(1) Check for liquid leak. ◦
(2) Check that the relief valve does
not protrude or swell.
(1) Check that no fluttering sound is
generated during the relay
operation.
(2) Check the contacts for damage.
(1) While performing a unit
operation of the inverter, check
the balance output voltage
among the individual phases.
(2) Carry out a sequential
protection operation test, and
check the protective and display
circuits for any abnormality.
(1) Check for abnormal vibrations
and noise
(2) Check the joints for loosening.
Check for clogging.
Inspection cycle
Periodic
Daily
Annual Biennial
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6 - 2
Inspection method Criterion Test equipment
See Section 2.1, "Installation."
Check visually and by listening.
Measure the voltage between the
main circuit terminals R, S, and T.
The ambient temperature must Thermometer,
be within -10°C to +50°C without hygrometer,
congelation. The ambient recorder
humidity must be 90% RH or less
without condensation.
There must be no abnormality
found.
The measured voltage must be Tester, digital
within the allowable tolerance for multimeter
AC power voltage.
Disconnect all input and output cables
500 VDC class
from the inverter's main circuit terminal
megger
block, detach the control circuit terminal
block from the inverter, and remove the
jumper for switching the inverter's
internal filter function. Subsequently, The measured ground resistance
measure the insulation resistance must be 5MΩ or more.
between the ground terminal and the
jumper connecting all the following
terminals:
R, S, T, U, V, W, P, PD, N, RB, R0, and
T0
Retighten loose screws and bolts.
Check visually.
Check visually
Check visually
Remove all cables from the
inverter's main circuit terminal block.
Use a tester (in 1Ω range mode) to
measure the following:
- Resistance between terminals R,
S, and T and terminals P and N
- Resistance between terminals U,
V, and W and terminals P and N
Check visually.
Check by listening.
Check visually.
Measure the voltage between the
cables connected to the main circuit
terminals U, V, and W.
There must be no abnormality
found.
There must be no abnormality
found.
There must be no abnormality
found.
There must be no abnormality
found.
See Section 6.5, "Method of
Checking the Inverter and
Converter Circuits." Standard
operating life of power
module(IGBT,IPM,Diode and
Thyristor ) until replacement: 10 6
cycles of starting and stopping
(*3)
Analog tester
There must be no abnormality Capacitance
found.
meter
Target operating life until
replacement: 10 years
(*1) (*3)
There must be no abnormality
found.
There must be no abnormality
found.
The inter-phase voltage balance
must be as follows:
200 V class models: 4 V or less
400 V class models: 8 V or less
Short-circuit or open the protective
circuit outputs as a simulation. An error must be detected
according to the sequence.
Turn the fan manually during the
inverter power-off status.
Check visually.
Check visually.
(1) Check that all LEDs light up
normally.
◦
Check visually.
(2) Clean the monitor. ◦ Clean the monitor with a rag.
Check that meter readings are
normal.
(1) Check for abnormal vibrations
and noise.
(2) Check for unusual smells.
Check the ground resistance
between all motor terminals and the
ground terminal with a megger.
◦
◦
◦
Check the meter readings on the
panel.
Check vibrations and noise visually,
by listening, and with physical
senses.
Check for any unusual smells
caused by overheating or damage.
The fan must rotate smoothly.
There must be no abnormality
found.
Standard operating life until
replacement: 10 years
(*2) (*3)
The heat sink must not be
clogged.
The LEDs must light up normally.
The readings must meet the
standard and control values.
There must be no abnormality
found.
There must be no abnormality
found.
Digital
multimeter,
rectifier
instrument, and
voltmeter
Voltmeter and
ammeter
Remove the cables from the
500 VDC class
inverter's main circuit terminals U, V,
megger
and W, connect the motor wires (for
◦ three phases) with one another, and
The measured ground resistance
measure the ground resistance
must be 5MΩ or more.
between the motor wires and the
ground terminal.
*1 The operating life of the smoothing capacitor is under the influence of the ambient temperature. Refer to Section 6.6, "Smoothing-Capacitor Life Curve," as a standard for the
operating life until replacement.
*2 The operating life of the cooling fan varies depending on environmental conditions, including the ambient temperature and dust. Check the status of the cooling-fan operation
during daily inspections.
*3 The standard operating life (number of years or operation cycles) and the data described in Section 6.6, "Smoothing-Capacitor Life Curve," are based on the expected design
life, but they do not indicate the guaranteed life of any parts.
*4 When replacing to the capacitor stored for 3 years or longer, please have shakedown period as below.
Apply 80% of rated voltage for 1 hour.