How large circuit breaker is the 315kVA transformer

Dizzy, what's the problem? First, I didn't say how many kilovolt level transformers there are, and second, I didn't say how many higher-level circuit breakers are required to protect this transformer? Or what is the low-voltage circuit breaker that protects the user at the output end of this transformer?

Usually, the high-voltage side circuit breaker that protects the transformer is calculated according to the no-load current of the transformer multiplied by a certain overload factor. Or take a look at the appendix of GB1984 for yourself. There is a matching calculation of the circuit breaker and the transformer.

As for the low pressure side, it is 315000 (380*. This is the maximum current to protect the total low-voltage circuit breaker on the user side, note that my overload factor is selected, you can also choose overload according to your requirements, but not too high. In addition, your transformer is too small, it is best not to choose circuit breaker protection on the high-voltage side, or it is really a waste of circuit breaker, you can use the load switch and fuse combination electrical protection form, buy a high-voltage circuit breaker can buy two or three load switches.

If the combination appliance can be protected from overcurrent, it will save the cost of daily use. Save a little! The country is not very rich yet.

315 transformers.

The high-voltage side can use rings, and the low-voltage side uses a complete set of distribution cabinets.

The current on the low voltage side is 315 (, there is a 500A is enough, and the low voltage circuit breaker.

I don't quite understand that the relationship between voltage and power is not that voltage multiplied by current is equal to electrical power. So 315*380=119700kw and the low-voltage side upstairs gives 500aThat's 500*380=190000kw

Even if 100KVA can bring a limit current of 114A, it is only more than 13 kilowatts, and a 500A circuit breaker is a bit too big?

I don't know much either, so let's learn it.

The Electricity Bureau configuration is 630A! It mainly depends on your electricity load! It is allocated according to the electrical load! The high-voltage side of the fuse is generally 30A, what kind of transformer do you use? Dry or oily sleeping The latter can be overloaded for a short time!

The maximum load that a 315 kVA transformer can carry depends mainly on the power factor of the load.

315kva (kva is kilovolt ampere) is the rated capacity of the transformer, that is, the rated apparent power, which means that when the power factor is 1 (pure resistance load), its rated load capacity is 315*1 = 315 kilowatts.

If the power factor of the load is, then it can only carry a maximum load of 315* = kilowatts, and so on.

Exceeding the above load is considered an overload.

Of course, under normal circumstances, transformers can also overload some loads for a short time, which is another matter.

It can carry 250kW and the maximum current is 470A. The active power that the transformer can output is quite different according to the load power factor, and there are generally the following typical situations: the transformer is a stationary motor with a high power factor, and its power factor can generally be reached.

It can carry 250kW and the maximum current is 470A.

Supplement: The active power that the transformer can output is quite different according to the load power factor, and there are generally the following typical situations: the power factor of the transformer itself

A transformer is a stationary motor with a very high power factor, and its power factor can generally be reached.

According to the power formula p=scos there is p=scos =315.

In practice, the power factor of the transformer often depends on the line reactive power compensation and the power factor of the user's electrical type. COS is unattainable.

The power supply department requires the power factor of the line to be reached after the user is compensated for reactive power.

p=scosφ=315×

The internal power supply of the factory: At this time, the power factor of the transformer is most affected by the main electrical motor of the factory, and the power factor of the motor is low.

p=scosφ=315×。

The maximum monthly electricity consumption of the 315kva transformer user stove chain is 181,440 kWh.

315kva=315kw, then the transformer is at full load, its working power liquid group is p=, and the electricity consumption for a month is w=px24x30=181440 degrees. However, it is impossible for every household to use electricity in this way, which is beyond the financial ability of individuals.

The guaranteed value of the output capacity of the transformer in the rated state is expressed in kilovolt-ampere (kVA) (volt-ampere VA and megavolt-ampere MVA are not commonly used), and due to the high operating efficiency of the transformer, the rated capacity of the primary and secondary windings is usually used.

The design values are equal.

How much load can the 315kva transformer withstand, how much load can the transformer carry with the maximum current of 250kw, and now the installed transformer is equipped with a low-voltage power factor automatic compensator, and the lowest power factor is also judged. Hence the load on the 315kVA transformer can be carried. 315kva is the apparent power, considering the impact of the voltage drop on the load when the load starts, it should be put 20% of the rich amount, and the power factor is taken as (315-315*20%)*315*watts.

It is an apparent power circuit, not a purely resistive circuit, and may have inductance or capacitance. p=ui (u: unit v apparent power and power factor 1.)

Apparent power: In electrical technology, the product of the voltage and current rms value of the end button of a single-port network is excavated, that is, or apparent power, which is recorded as, that is, (1) Obviously, only when the single-port network is completely mixed by resistors, the apparent power is equal to the average power, otherwise, the apparent power is always greater than the average power (that is, active power), that is, the apparent power is not.

KVA is the apparent power of the transformer.

That is to say, the envy car stove is his total type of power, which can include active power and reactive power.

As for how they are distributed? It depends on the nature of your load. Assuming that your load power factor is (the lowest amount of power required for the destruction of the sail), he can take on the active power of 315 (kva)* (watch out for units).

2. In terms of the current output of the transformer (assuming that it is a distribution transformer, the low voltage is 400V). Then the output of the extra line current per phase is i2 = 315 * 1000 400 This is on the transformer nameplate, you can see, that is, the output current of each phase of the transformer only needs to be within the limit, which is safe.

315kva refers to the apparent power, the unit is called kilovolt ampere, the general transformer, welding machine is used to indicate the capacity, and a bucket guess some commonly used household appliances, motors, etc. are used to indicate the capacity of active power (kilowatts or watts to change sales). A transformer is a device that uses the principle of electromagnetic induction to change the alternating voltage, and the main components are the primary coil, the secondary coil and the iron core (magnetic core). The main features are:

Voltage conversion, current conversion, impedance conversion, isolation, voltage regulation (magnetic saturation transformer), etc.

According to the use, it can be divided into: power transformer and special transformer (electric furnace transformer, rectifier transformer, power frequency test transformer, voltage regulator, mine transformer, audio transformer, intermediate frequency transformer, high-frequency transformer, impact transformer nuclear attack, instrument transformer, electronic transformer, reactor, transformer, etc.). Circuit symbols often start with t.

Example: T01, T201, etc.