Pay attention to the following points when installing low-voltage circuit breakers:
1.Before installing the circuit breaker, it is necessary to check whether the oil stain on the working surface of the armature has been wiped off, so as not to interfere with its working efficiency.
2.When installing the circuit breaker, it should be installed vertically to avoid affecting the action accuracy and on-off capability of the release, and insulation protection should be installed.
3.When the circuit breaker terminal is connected to the bus bar, no torsional stress is allowed, and the appropriateness of the short-circuit tripping value and thermal tripping value must be checked.
4.The power supply incoming line should be connected to the upper column head on the side of the arc extinguishing chamber, and the load outgoing line should be connected to the lower column head on the side of the release, and the connection line with an appropriate cross-sectional area should be selected according to the regulations to avoid affecting the overcurrent trip. The protective properties of the clasp.
5.The wiring of the operating mechanism and the electric mechanism of the circuit breaker must be correct. During electric operation, switch jumping should be avoided, and the power-on time should not exceed the specified value.
6.During the closing and opening process of the contacts, there should be no jamming between the movable part and the parts of the arc chamber.
7.The contact surface of the contact should be flat, and the contact should be tight after closing.
8.The short circuit trip value and thermal trip value must be set correctly according to the line and load requirements.
9.Before use, use a 500V megohmmeter to measure the insulation resistance between the live body and the frame, between poles, and between the power side and the load side when the circuit breaker is disconnected. Make sure that the insulation resistance is greater than or equal to 10MΩ (marine circuit breaker Not less than 100MΩ).
The following are the requirements for low-voltage circuit breaker wiring:
1.For the wire terminals exposed outside the box and easily accessible, insulation protection is required.
2.If the low-voltage circuit breaker has a semiconductor tripping device, its wiring should meet the phase sequence requirements, and the action of the tripping device should be reliable.
The following are the installation, adjustment and test requirements for DC fast circuit breakers: 1. During installation, it is necessary to prevent the circuit breaker from toppling, colliding and violent vibration, and take appropriate anti-vibration measures between the foundation channel steel and the base.
2 .The distance between the pole centers of the circuit breaker and the distance to adjacent equipment or buildings should not be less than 500 mm. If this requirement cannot be met, it is necessary to install an arc barrier whose height is not less than the total height of the single-pole switch. There must be a space of not less than 1000mm above the arc extinguishing chamber. If this requirement cannot be met, when the switching current is below 3000 amps, it is necessary to install an arc shield 200 mm above the interrupter of the circuit breaker; Install arc baffles.
3.The insulating lining in the arc extinguishing chamber must be intact and the arc passage must be unblocked.
4.The contact pressure, opening distance, breaking time, and the insulation resistance between the arc extinguishing chamber support screw and the contact after the main contact is adjusted must meet the requirements of the product technical documentation.
Post time: Jul-06-2023