LMZK-10 current transformer

The Model LMZK-10 is a ring type resin casting split core current transformer. Some clients also called it as TTCC. This model split core ct can be used both for measurement and microcomputer protection of electrical equipment in 11KV and 35KV AC power system. It is widely used in compact fully insulated ring network switchgears such as ABB-Safe Ring/Safe Plus…and cable distribution boxes. The split core current transformer can be directly installed at the inlet andoutlet cables.The slice is imported silicon material.
We used imported silicon material and using our mature advanced producing technology we make sure our transformer has very goog linear and more than 20 years using life in order to be qualified with all the jobs. The semicircular ring core and secondary windings are vacuum poured by insulated resin.
All of our current transformers are strictly comply IEC60044-1, IEC 61869-2, NTC 2205, GB1208-2006, ANSI/IEEE C57.13.                                                                                                                                                                                                                                                                                                                                                                    

technical parameter :

LMZK-10 current transformer are in accordance withGB/T20840.1.2 and EC61869-1.2 standards

Rated insulation level 24/65/125kV

Rated frequency 50Hz or 60Hz

Rated secondary current 5Aor 1A

Ambient temperature -5℃~ +40℃

Power factor of load: COSΦ=0.8(lagging).

Rated secondary current: 5A or 1A.

Rated frequency: 50 or 60Hz.

Anti-Pollution grade: Class II.

Ambient temperature: -5℃-40℃,daily average temperature not more than 30℃.

Altitude: ≤1000m.

Standard: GB20840.1 GB20840.2

Main requirements of LMZK-10 protection transformer :   

Reliable insulation
Sufficiently large accuracy limit factor
Sufficient thermal and dynamic stability

When a large current occurs in the line under test, the transformer should be saturated in an appropriate range to protect the measuring instrument.

The LMZK-10 current transformer for protection can meet the requirements of the accuracy level under the rated load. The maximum primary current is called the rated accuracy limit primary current. The accurate limit factor is the ratio of the rated accurate limit primary current to the rated primary current. When the primary current is large enough, the iron core will saturate and cannot reflect the primary current, and the accurate limit coefficient represents this characteristic. The accuracy level of the protection transformer is 5P, 10P, etc.

 The  LMZK-10 current transformer  mainly cooperates with the relay device, and provides a signal to the relay device to cut off the faulty circuit in the event of a short-circuit overload and other faults in the line to protect the safety of the power supply system. The working conditions of the protection miniature current transformers are completely different from those of the measuring transformers. The protection transformers only start to work effectively when the current is several times larger than the normal current.

product structure ： 

LMZK-10 current transformer uses imported silicon steel sheet with high magnetic permeability as magnetic conductive material, which has the characteristics of divisible iron core and low magnetic circuit loss. Its semi-circular iron core and secondary winding are made of epoxy resin vacuum Cast in a flame retardant plastic alloy housing, moisture-proof and maintenance-free.                                                                                                                                                                                                               

During installation, clamp the two semi-circles on the split-phase cable, and hold them tightly with a hoop, which is integrated with the cable, harmonious and beautiful, and is suitable for 10kV cables of 35mm2-400mm2. The hoop is made of high-quality stainless steel, which is strong Reliable, no eddy currents. This series of current transformers are divided into the following types according to current changes, accuracy levels and rated loads. For specific parameters, please refer to the parameter table corresponding to each model. This series of current transformers can be divided into taps according to user requirements, that is, multi-current ratio transformers.

LMZK-10 current transformer function：                                                                                                                                                                                           

Transformer for power system is a special transformer that transmits the information of high voltage and high current of the power grid to the metering, measuring instrument, relay protection and automatic device of the secondary side of low voltage and low current. It is a primary system and a secondary system. The primary winding is connected to the power grid, and the secondary winding is connected to the measuring instrument and the protection device.                                                               

The transformer cooperates with measuring instruments and metering devices to measure the voltage, current and electric energy of the primary system; cooperates with relay protection and automatic devices to form electrical protection and automatic control of various faults in the power grid. The quality of the transformer performance directly affects the measurement and measurement accuracy of the power system and the reliability of the action of the relay protection device.                                                                                   

outline dimension drawing :