Protective functions – MITSUBISHI ELECTRIC FR-A500L User Manual
Page 47
PROTECTIVE FUNCTIONS
36
Daily and Periodic Inspection
Interval
Periodic
Area of
Inspec-
tion
Inspection
Item
Description
Daily
1
year
2
years
Method
Criterion
Instrument
Inverter
module,
Converter
module
Check resistance
across terminals.
{
Disconnect cables 1 , L 2 , L 3, +, -, and U, V, W, +, -> with tester Ω . (See the following Analog tester Smoothing (1) Check for liquid leakage. (2) Check for safety valve projection and (3) Measure electrostatic { { { (1), (2) Visual check. capacity meter. (1), (2) No fault. Capacity Relay (1) Check for chatter during operation. (2) Check for rough surface on contacts. { { (1) Auditory check. (1) No fault. Main Resistor (1) Check for crack in resistor insulation. (2) Check for open cable. { { (1) Visual check. Cement resistor, (2) Disconnect one end and measure (1) No fault. be within ± 10% of indicated Tester, digital Control Operation (1) Check balance of output voltages (2) Perform sequence protective operation { { (1) Measure voltage across inverter (2) Simulatively connect or (1) Phase-to- phase voltage (2) Fault must occur because Digital Cooling fan (1) Check for unusual vibration and noise. (2) Check for loose connection. { { (1) Turn by hand with power off. (2) Re-tighten (1) Smooth rotation. (2) No fault. Cooling Cooling fan Is the power supply's { Measure with a tester. 24V 2.4V Tester Display (1) Check if LED lamp is blown. (2) Clean. { { (1) Light indicator lamps on panel. (2) Clean with rag. (1) Check that lamps are lit. Display Meter Check that reading is { Check reading of Must satisfy Voltmeter, General (1) Check for unusual vibration and noise. (2) Check for unusual odor. { { (1) Auditory, sensory, visual checks. (2) Check for unusual odor due to (1), (2) No fault. Motor Insulation (1) Check with megger (across terminals { (1) Disconnect cables from U, V, W, (1) 5M Ω or more 500V megger
from inverter and
measure across
terminals R, S, T, P, N
and U, V, W, P, N
range of 100
pages)
capacitor
bulge.
capacity.
(3) Measure with
(3) 85% or more
of rated capacity.
meter
(2) Visual check.
(2) No fault.
circuit
wire-wound
resistor.
with tester.
(2) Error should
resistance
value.
multimeter
circuit
Protective
circuit
check
across phases with
inverter operated
independently.
test to make sure of
no fault in protective
and display circuits.
output terminals
U-V-W.
disconnect inverter
protective circuit
output terminals.
balance within
8V for 400V.
of sequence.
multimeter,
rectifier type
voltmeter
system
power
supply
output voltage correct?
normal.
meters on panel.
specified and
management
values.
ammeter, etc.
overheating,
damage, etc.
resistance
and ground
terminal).
including motor
cables.