What is the reason for the sound of the low voltage cabinet when the air is opened and the cable is

1. The circuit breaker (empty open) is overheated and causes tripping.

There are generally three reasons for circuit breaker tripping, the first is overload, the second is short circuit, and the third is leakage.

2. The automatic air switch, also known as the low-voltage circuit breaker, can be used to turn on and off the load circuit, and can also be used to control the motor that starts infrequently.

It is equivalent to the sum of some or all the functions of electrical appliances such as knife switches, overcurrent relays, loss of voltage relays, thermal relays and leakage protectors, and is an important protective appliance in the low-voltage distribution network.

3. After the main contact of the circuit breaker is closed, the free trip mechanism locks the main contact in the closing position.

The coil of the overcurrent tripper and the thermal element of the thermal tripper are connected in series with the main circuit, and the coil of the undervoltage tripper and the power supply are connected in parallel. The reason why the air switch trips when it heats up.

When the circuit is short-circuited or seriously overloaded, the heat increases sharply, and the armature of the overcurrent tripper is engaged, so that the free tripping mechanism acts, and the main contact disconnects the main circuit.

Possible causes: The current of the circuit where the air opening is located has exceeded the rated current of the air opening, and the air switch will trip after 1 hour under the condition of double the rated current (thermal tripping, at this time, it is the tripping caused by the deformation of the temperature-sensing bimetal sheet inside the air opening), and if it reaches 7 times the rated current, the air opening will trip immediately (electromagnetic tripping, at this time, it is the trip caused by the action of the current trip device inside the air opening).

What other load does this empty open control, this load is likely to start at night or suddenly increase, causing the empty open overcurrent trip.

There is an air switch with overload protection and leakage protection, and the reason for the heating trip: electrician world.

1. The total load exceeds the load capacity of the air switch, or the load circuit is short-circuited;

2. The contact pressure of the air switch is small, or the contact of oxidation and corrosion is poor;

3. The contact of the wiring screw of the air switch is poor, and the wiring point is heated; The reason why the air switch trips when it heats up.

4. The total load exceeds the load capacity of the transmission wire, and the wire and terminal point are heated;

5. The quality of the air switch is poor, the name does not live up to the truth, and the nominal current index cannot be reached;

6. The parameters of the air switch have changed, and the load capacity has decreased;

7. The power supply voltage exceeds the standard or suddenly exceeds the standard due to sudden reasons;

8. Air switch with leakage protection, leakage fault occurs in the load circuit.

The sizzling sound of the low-voltage cabinet is generally caused by poor contact and ground discharge.

There are two possible scenarios for the following:

1. The cable cross-section is too small, and the use load is too large, resulting in empty opening and cable heating; The low-voltage cabinet has a sizzling sound, the interphase insulation has broken down, there is a phase short circuit, or the ground insulation has broken down, and the ground is discharged.

2. The cable is in poor contact and the screws are loose, resulting in empty opening and cable heating; The low-voltage cabinet has a sizzling sound, the interphase insulation has broken down, there is a phase short circuit, or the ground insulation has broken down, and the ground is discharged.

It can be crimped with a large wiring nose and then bolted.

How to bend the 120 cable into the cabinet.

It can be crimped with a large wiring nose and then bolted.

Whether you need a transformer depends on the voltage of your load and the situation of the existing equipment, if the voltage level of your electrical equipment is the same as the supply voltage, or although it is not the same but the existing transformer capacity can meet your requirements, then you do not need to configure a transformer. Otherwise, a transformer must be configured.

About the distribution cabinet: 400A air opening is just enough, there is no margin can also be selected, if you need an insurance coefficient, try to choose a large level of air opening 500A air opening is not common, 630A is common. My personal opinion is to choose 630a.

Wire: 120mm copper core, 200mm or more aluminum core.

200kw, the current is less than 400A, it can be equipped with 500A air opening, and the power distribution cabinet can be used with power box, GGD, GCK, etc.

240 copper core cable is used.

As for whether to match the transformer, it depends on the power supply bureau.

It depends on whether the capacity of the transformer near you is enough If you can't bring your 200kw load, you have to install an independent transformer If the power load is 200 kilowatts, it is not a full load operation, you can consider 150 cables, if it is a single-phase 220 load, 35 cables can be opened, three-phase power can be equipped with 400A, single-phase 220, with a 125 or 150A.

Whether a transformer is needed depends on the opinion of the power supply department. Generally, the 200kw load power supply bureau provides 10 kV power supply, so the customer needs to install a transformer. What form does the high-voltage side of the transformer take, but also according to the requirements of the power supply bureau, generally in the form of high-voltage drop switch, if the power supply department insists on using 10 thousand volt high-voltage cabinets, it has to obey.

In short, they ask for electricity from the power supply department, so most of them have the final say.

It needs to be equipped with 200kVA transformer, distribution cabinet, 1 incoming metering cabinet, 1 capacitor cabinet and 1 outlet cabinet.

The incoming switch is equipped with 400A, and the outgoing switch is equipped with 5 x 100A.

Possible Causes:

1. Because of the poor contact, the current slowly turns red and burns out during normal operation at the joint;

2. The local conductor of the cable is damaged or mechanically hard damaged, the current carrying capacity is reduced, and the heating is red and burned;

3. The local insulation of the cable is defective, and the wire is damaged by slow discharge, and the current carrying capacity is reduced, and it is red and hot, and burns out;

4. Short circuit of cable or load, fault of empty opening, etc.

The question is not very clear, is it the same phase that has a weak point and is broken, or is it a short circuit between the two wires and burned?

If it's the first one, it's a problem with the line (the current is normal current, because the cable is damaged and broken, and of course the circuit breaker doesn't jump).

If it is the second type, then it is necessary to calculate whether the circuit breaker is suitable for matching with the line:

The selection principles of circuit breaker are: first, the rated current of the circuit breaker is less than the current that the lower end line can carry for a long time, and is greater than the load capacity of the lower end; The instantaneous trip current of the second circuit breaker is less than the calculated current of the short circuit of the lower end line. The line is too long and too thin from the power supply end, and the circuit breaker is very large, and the short-circuit current cannot reach the instantaneous detaching current value, of course, it cannot be tripped in time.

Possible Causes:

1. The terminal air opening option is too large;

2. The cable is too small

3. Damage to the empty opening (contact bonding, damage to the tripper);

4. What is burned is the cable before the empty opening.

Air opening is greater than or equal to 70, contactor CJX2-6311.

Air open should be 70A, the contactor is CJX2-8011 or CJX2-6311, if the line is not too long (30 meters), you can use 3 10 square copper core wires and 1 square copper core wire for the zero line.

The circuit breaker uses M1-63A 3300, with two 10 square wires in parallel, the safe current carrying capacity of 25 square lines is about 80 amps, with two is a bit small, the water heater lead can be replaced, and the power of a washing machine and energy-saving lamps adds up to more than 200 watts, which is negligible.

The current of the 380V48 kW electric heating pipe is about 75A, and you can determine the capacity of the switch and other electrical appliances according to the current.

The calculated current is about 73A, considering the margin, it is recommended to choose 100A for air opening, and the contactor takes Schneider as an example to choose LC1D11500M5C, and the minimum cable is 25 square cables.

Rated current of 36kw electric heating pipe:

I p air open should be 70A, the contactor is CJX2-8011, if the line is not too long (30 meters), you can use 3 10 square copper core wires and 1 square copper core wire for the zero line; The power of other loads is small, which basically does not affect the balance of the three phases.

The rated current is estimated to be about 50A, plus the use factor, etc., and the air open contactor should be selected according to the 80A grade The wire is 16 square or more is the best.

27 kW * current per phase).

36kw*current per phase).

The maximum current of 10 square wire is 40 A, change to 3 * 16 + 2 * 10 cable, use M1-63A 3300 for circuit breaker, replace CJX2-6311 with contactor, use two 10 square wires in parallel, 25 square line safety current carrying capacity is about 80 A, with two is a bit small, water heater lead or replace it, if it is only for temporary use, long-term use or replacement, the power of a washing machine and energy-saving lamps adds up to more than 200 watts, which is negligible.

The electrical specification is to be tinned, but the current terminal blocks and copper noses are all tinned products (those that look tin-colored on the outside are tin-plated noses). We don't use it anymore.

Hello: According to the specification, it should be shabu-shabu.

According to your power and the cable, if the cable conductor is not a loss (commonly known as non-standard wire), the heat is normal, but it should be noted that if it is PVC insulation, it should not exceed 45 in the summer, and the polyethylene should not exceed 65 in the bend.

Not with 63's. If the capacity is too large, it will not be protected. If the switch is greater than the carrying capacity of the wire, there will be overload and no tripping, which will cause the cable to heat up and cause fire. So try to match the cable and the brake. Or the gate is slightly smaller, and the gate is used to protect the line.

6 square wires into the house, if it is a building, that is, the wire through the pipe into the house, according to the "wire through the pipe safety current carrying capacity", the safety current is 34a, so the rated current of the air switch should not be large and 34a, if the rated current of the air switch is greater than 34a, there are potential safety hazards.

Therefore, the electricity current in your home should not exceed 34A. If the power supply is insufficient, the power supply system should be replaced. If the wire is laid open-wired, the safe current of the wire is 56A.

An air switch, also known as an air circuit breaker, is a type of circuit breaker. It is a switch that automatically disconnects whenever the current in the circuit exceeds the rated current. The air switch is a very important electrical appliance in the low-voltage distribution network and the power drive system, which integrates control and a variety of protection functions.

In addition to completing the contact and breaking circuits, it can also protect the circuit or electrical equipment from short circuits, serious overloads and undervoltages, and can also be used to start the motor infrequently.

Tripping: First of all, determine whether the tripped air switch is the main switch in the distribution box at home or the shunt outgoing switch.

If the main switch is not tripped, but the shunt switch trips, it means that there is a problem with the wiring of the power supply line of the high-power electrical appliance, that is, a plurality of high-power electrical appliances are connected to the same shunt switch.

If the shunt switch does not trip and the main switch trips, calculate whether the sum of the power of household appliances exceeds the approved capacity of power supply, and check whether the total switch capacity matches the approved capacity of power supply.

If the sum of the power of household appliances exceeds the approved capacity of power supply, reduce the number of household appliances used at the same time (especially high-power household appliances) and apply to the power supply company for capacity increase; If the sum of the power of household appliances does not exceed the approved capacity of power supply, but the total switching capacity is less than the approved capacity of power supply, the main switch that matches the approved capacity of power supply shall be replaced. At the same time, it should be reminded that the starting current of some high-power electrical appliances is large, and the impact of the starting current should be considered when calculating the power.

With 6 square wires into the home, you need to be equipped with an air switch of about 32 amperes as the main control switch.

More than 80% of daily air switches are burned out because the screws are not tightened. Of course, there are some other reasons, although these reasons are very unlikely, such as unqualified wiring process, unqualified switch quality, water ingress in the air opening, conductive dust intrusion in the air opening, etc. As for the overload and burnout caused by too much electrical equipment, the air opening itself has short circuit and overload protection.

Because the air opening is mainly to protect the wires, not to protect the electrical equipment. Therefore, when increasing the rated current of the empty opening, if the rated current of the empty opening is larger than the safe ampacity of the wire, then the wires may be overloaded and burned. In general, the armature of the overcurrent tripper is in the released state.

6 square copper core wire, after checking the cable comparison table, the open wire laying safety interception flow is about 50a.

According to the wiring requirements of the circuit breaker, it is best that the air switch should not exceed 40A when the dark wire is laid.

You don't have to worry too much about the situation you are talking about, you should consider replacing the air opening of the Model 63. At present, the current value of the micro air opening, its overload and jumping current value should be said to be not necessarily accurate, so it can only be said that it is better to change to a larger model.

No, the copper wire has a strong overload capacity, and it is difficult to burn out if it is more than n times.

You should change to a 63A, the overload of the appliance is not protected by an empty switch, but a single overcurrent protector.