Omron 3G3RX Series, User Manual

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6-7
6-1 Inspection and Maintenance
6
Inspection and Maintenance
Megger test
• For a megger test of the external circuit, be sure to disconnect all the terminals of the Inverter so
as not to apply the test voltage to the Inverter.
• Use a high resistance tester for a power distribution test of the control circuit. Do not use a megger
or buzzer.
• Conduct an Inverter megger test only to the main circuit, not to the control circuit.
• Use a 500 V DC megger for a megger test.
• For a megger test of the Inverter main circuit, remove the short-circuit bar used for switching the
Inverter built-in filter function and then short-circuit terminals R/L1, S/L2, T/L3, U/T1, V/T2, W/T3,
P/+2, +1, N/-, RB, Ro, and To with the wires, as shown below.
After the megger test, remove the short-circuit wires from terminals R/L1, S/L2, T/L3, U/T1, V/T2,
W/T3, P/+2, +1,
N/-, RB, Ro, and To, and reconnect the short-circuit bar for switching the Inverter built-in filter
function.
Note that the RB terminal is provided only for the Inverters with 22 kW or lower capacity.
Withstand Voltage Test
Do not conduct a withstand voltage test on any part of the Inverter.
Doing the test is dangerous and may cause damage or deterioration to the parts inside the Inverter.
Checking the Inverter and Converter
• The quality of the Inverter and converter can be checked using a tester.
(Preparation)
Disconnect the externally connected power supply wires (R/L1, S/L2, T/L3), the motor connection
wires (U/T1, V/T2, W/T3), and the regenerative braking resistance (P/+2, RB).
Prepare a tester. (Usable range is 1
Ω
measurement resistance.)
(Checking method)
• The quality can be judged by measuring the conduction state of Inverter main circuit terminal
blocks R/L1, S/L2, T/L3, U/T1, V/T2, W/T3, RB, P/+2, and N/- while alternating the tester polarity.
Note 1: Before checking, measure the voltage between P/+2 and N/- at DC voltage range in advance, and
confirm that the smoothing capacitor is sufficiently discharged.
R/L1
S/L2
T/L3
Ro
To
Ground terminal
Power
supply
Do not connect the
power wire.
500 V DC megger
Be sure to remove the short-circuit bar for
switching the built-in filter function.
Ground terminal
P/+2 +1 N/- RB
U/T1
V/T2
W/T3
Do not connect to the
motor.
Motor
IM