LDBJ9-40.5 series current transformersDetailed product description：

The LDBJ9-40.5 current transformer is a contact box type current transformer, suitable for use in power systems with a rated frequency of 50Hz or 60Hz and a rated voltage of 35kV and below, for energy metering, current measurement, and relay protection. It is specifically designed for KYN61-40.5 high-voltage switchgear. This product complies with the standards of IEC60044-1 and GB1208 "Current Transformers".
Introduction to the Structure of LDBJ9-40.5 Current Transformer
This type of current transformer is a fully enclosed epoxy resin casting structure, and the P1 end of its primary winding is set inside the contact box.

Technical parameters of LDBJ9-40.5 current transformer

Rated primary current (A)	Accurate level combination	Rated output (VA)	Rated short-time thermal current (Ith) (kA)	Rated dynamic stability current (Idyn) (kA)
200~300	0.2/10P10 0.5/10P10 0.2/10P20 0.5/10P20 0.2/0.5/10P10 0.2/0.5/10P20 0.2/10P10/10P10	20/50 30/50 20/20 30/20 20/30/30 20/30/15 30/30/30	150I1n	375I1n
four hundred			forty-five	one hundred and twelve point five
five hundred			sixty-three	one hundred and thirty
six hundred
eight hundred	0.2/10P10 0.5/10P10 0.2/10P20 0.5/10P20 0.2/0.5/10P10 0.2/0.5/10P20 0.2/10P10/10P10	30/50 50/50 40/30 50/30 30/40/40 30/40/20 40/40/40	eighty
1000~1200
one thousand and five hundred
2000~3000			one hundred	one hundred and sixty

1. Rated insulation level: 40.5/95/185kV
2. Rated secondary current: 5A, 1A
3. The rated primary current, accuracy level combination, rated output, and rated dynamic and thermal stability currents are shown in Tables 1 and 2
4. LDJ6-35 Pollution Level: Level II
5. The partial discharge level of the product meets the requirements of GB1208 "Current Transformers".
LDBJ9-40.5 current transformer ratio parameters
The principle of current transformer is based on the principle of electromagnetic induction. A current transformer is composed of a closed iron core and winding. Its primary winding has very few turns and is connected in series with the line that needs to measure the current, so it often has all the current flowing through the line. The secondary winding has a relatively large number of turns and is connected in series with the measuring instrument and protection circuit. When the current transformer is working, its secondary circuit is always closed, so the impedance of the measuring instrument and protection circuit series coil is very small, and the working state of the current transformer is close to a short circuit.