CHINT NQ2 Series, User Instruction

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NQ2 Series Electromagnetic Starter
06
Table 5 Cross-sectional area of connecting wires of the main circuit
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
＜
＜
＜
＜
＜
＜
＜
＜
＜
Rated operating current of motor, I (A) Cross-sectional area of connecting wires of main circuit (mm²)
1
1.5
2.5
4
6
10
16
25
35
4 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.
Table 6 Examples of Fault Analysis and Troubleshooting
Cause anaylsis Troubleshooting method and precautions Symptoms
Fine tune the current dial so that the product’s set
current matches the actual current of the motor.
The setting current value of thermal relay is smaller
than the actual operating 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.
Strong shock or viberation
The motor start requires a certain interval, with
frequency no more than 30 times per hour.
Frequent starts of the motor
Choose standard wires according to Table 5.
The cross-sectional area of connecting wires of the
main circuit is too small.
The starter
mis-operates
before being
overloaded
The setting current value of thermal relay is bigger
than the actual operating current of the motor.
Fine tune the current dial so that the product’s set
current matches the actual current of the motor.
The cross-sectional area of connecting wires
of the main circuit is too big.
Choose standard wires according to Table 5.
The starter
fails to
operate after
being
overloaded
The wiring of the starter becomes loose or falls
The coil voltage is too low or voltage fluctuation is
too big.
The setting current value of thermal relay is too
small which leads to the failure of product reset.
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.
The starter
fails to
operate