Maintenance - CHINT NQ2 Series User Instruction

Table 5 Cross-sectional area of connecting wires of the main circuit
Rated operating current of motor, I (A)
0 I≤8 ＜
8 I≤12 ＜
12 I≤20 ＜
20 I≤25 ＜
25 I≤32 ＜
32 I≤50 ＜
50 I≤65 ＜
65 I≤85 ＜
85 I≤100 ＜
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Maintenance

Check whether the thermal relay inside the starter operates reliably on a regular basis (once a month)
by adjusting the current dial and reducing the setting current until the relay operates. Then, restore the
current dial to the original position.
Note: Do not dismantle and repair the product at will. Once the product is found damaged, replace it
immediately.
Symptoms
The setting current value of thermal relay is smaller
than the actual operating current of the motor.
The starter
Strong shock or viberation
mis-operates
before being
overloaded
Frequent starts of the motor
The cross-sectional area of connecting wires of the
main circuit is too small.
The starter
The setting current value of thermal relay is bigger
fails to
than the actual operating current of the motor.
operate after
The cross-sectional area of connecting wires
being
of the main circuit is too big.
overloaded
The wiring of the starter becomes loose or falls
The starter
The coil voltage is too low or voltage fluctuation is
fails to
too big.
operate
The setting current value of thermal relay is too
small which leads to the failure of product reset.
Cross-sectional area of connecting wires of main circuit (mm²)
Table 6 Examples of Fault Analysis and Troubleshooting
Cause anaylsis
NQ2 Series Electromagnetic Starter
1.5
2.5
10
16
25
35
Troubleshooting method and precautions
Fine tune the current dial so that the product's set
current matches the actual current of the motor.
Inspect the installation site and troubleshoot to
prevent the product from being placed in an
environment where there is strong shock or
viberation.
The motor start requires a certain interval, with
frequency no more than 30 times per hour.
Choose standard wires according to Table 5.
Fine tune the current dial so that the product's set
current matches the actual current of the motor.
Choose standard wires according to Table 5.
Tighten the connecting screws and check whether
the screws are loosen before use.
Increase the power supply voltage or add stabilized
voltage equipment.
Fine tune the current dial toward the bigger current
direction.
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