Shanghai Huabang Industrial Business Network - zero-sequence current transformer

[zero-sequence current transformer]LJZ- �� 150 type zero sequence current transformer

2026-6-15 19:54:50

Technical parameters of LJZ - �� 150 zero sequence current transformer

Appearance and installation dimensions

[zero-sequence current transformer]LSJ Three phase integrated zero sequence current transformer

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LSJ three-phase integrated zero sequence current transformer

[zero-sequence current transformer]LJK type zero sequence current transformer

2026-6-15 19:54:33

The LJK series square, open-ended zero sequence current transformer is a cable type, with an ABS engineering plastic shell and resin casting for full sealing. It has good insulation performance, beautiful appearance, high sensitivity, good linearity, reliable operation, and easy installation. Its performance is superior to general zero sequence current transformers. Widely applicable, it is not only suitable for electromagnetic relay protection, but also for electronic and microcomputer protection devices. Users can choose the appropriate zero sequence current transformer according to the operation mode of the system (neutral point grounded, neutral point ungrounded, high resistance grounded, low resistance grounded, arc suppression coil grounded).

Terms of Use
1. Environmental temperature: -10 �� to 60 ��, with a daily average temperature not exceeding+40 ��
2. Altitude �� 1000m (special order for high-altitude use)
3. Relative humidity �� 85%
4. The surrounding medium is free of conductive dust, conductive metals, corrosive gases, mold, etc. that may damage the insulation.
Product category and main data
1. Voltage 0.38-66KV
2. Grid frequency 50Hz
3. Same name end, once inserted from the front "L1" side of the transformer, and the second is "K1"
4. The model, data, and external dimensions are shown in the chart.

Install
1. The installation of the integral transformer should be carried out before laying the cable, and the cable should pass through the transformer during laying.
2. The installation of open-ended transformers can be carried out at any time, and the specific installation method is as follows:
(1) Remove the connecting pressure plates of transformers' K1 'and' K2 '.
(2) Loosen and remove the two hexagonal bolts on the top of the transformer, and the transformer will be divided into two parts.
(3) Insert the transformer onto the cable, clean the two contact surfaces, apply a thin layer of rust proof oil, align the two parts of the transformer, and tighten the hexagonal socket bolts to avoid affecting performance.
(4) Fix the connecting piece on "K1 '" and "K2'".
(5) The upper and lower parts of the open type transformer cannot be interchanged with other transformers.

[zero-sequence current transformer]LXZ1,2 type zero sequence current transformer

2026-6-15 19:54:25

LXZ1, Type 2 zero sequence current transformer

[zero-sequence current transformer]LMZB1-0.5 type zero sequence current transformer

2026-6-15 19:54:16

LMZB1-0.5 type zero sequence current transformer

[zero-sequence current transformer]LJZ-0.66 Zero sequence current converter

2026-6-15 19:54:06

LJZ-0.66 Zero Sequence Current Converter

[zero-sequence current transformer]LJZ- �� 75 type zero sequence current transformer

2026-6-15 19:53:57

LJZ - �� 75 type zero sequence current transformer

[zero-sequence current transformer]LCT-7 type open close zero sequence transformer

2026-6-15 19:53:49

1. Usage environment
Environmental temperature: -20 ��~50 ��;
Relative humidity: �� 90%
Atmospheric pressure: 80kPa~200Kpa;
2. AC voltage: 66kV~4000kV;
3. Zero sequence current:
Primary side 1~36A (customized for 36A and above, secondary side 20~30mA)

LCT-7 type switchable zero sequence transformer

[zero-sequence current transformer]LSZ Three phase integrated zero sequence current transformer

2026-6-15 19:53:40

LSZ three-phase integrated zero sequence current transformer

[zero-sequence current transformer]LXBK2- �� 150 type zero sequence current transformer

2026-6-15 19:53:31

LXBK2- �� 150 type zero sequence current transformer

[zero-sequence current transformer]LXBK/LXBK1 series zero sequence current transformer

2026-6-15 19:53:21

LXBK/LXBK1 series zero sequence current transformer

[zero-sequence current transformer]ZCT-3 series zero sequence current transformer

2026-6-15 19:53:12

ZCT-3 series zero sequence current transformer

Product specifications: Mechanical dimensions: OD/ID * H 17.3/6.9 * 7.0
Main markets: Leakage protection switches, sockets, plugs, and household appliance protection

[zero-sequence current transformer]ZCT-2 series zero sequence current transformer

2026-6-15 19:53:04

Product specifications: Outsourced adhesive tape insulation, specific specifications can be made according to customer requirements.
Main markets: Leakage protection switches, sockets, plugs, and household appliance protection

ZCT-2 series zero sequence current transformer

[zero-sequence current transformer]ZCT1 series zero sequence current transformer

2026-6-15 19:52:55

ZCT1 series zero sequence current transformer

Model: ID/OD * HT
ZCT1-1A:5.8/16*8

ZCT1-1: 6.7/17*8

ZCT1-2: 8.8/22*9

ZCT1-3: 10.5/24*10

ZCT1-4: 14.8/30*10

The ZCT1 series zero sequence current transformer is mainly used for leakage protection switch plugs, detecting leakage current, providing reliable driving current for circuit breakers, and can also be used for monitoring electricity theft behavior in single-phase anti-theft electricity meters.
Leakage protection switch, socket, plug and household appliance protection

[zero-sequence current transformer]LX3-2,LX3-4,LX3-7(LJ),LXM series zero sequence current transformer

2026-6-15 19:52:46

I. Overview
LX3-2, LX3-4, and LX3-7 are equivalent to LJ zero sequence current transformers used in conjunction with relay protection devices or signal devices when generating zero sequence grounding currents in the system, to activate device components and achieve protection and monitoring.

2�� Model meaning

3�� Categories and main data of LX3-2, LX3-4, LX3-7 (LJ), LXM series zero sequence current transformers
(1) The new LX3-2, LX3-4, and LX3-7 are thick cable type zero sequence transformers, which are fully sealed with resin casting, resulting in better insulation performance, more beautiful appearance, and easier installation. This transformer is used in conjunction with DD11/60 type relays, with a secondary load of 10 ��.

Figure 1: Outline Dimensional Diagram of Series Transformers

Table 1 Dimensions of LX Series Transformers (Part 1)

new model	old model	Inside d	External D	Thick M	Hole center main r	mounting hole spacing	zero-sequence current	secondary current
LX3-2	LJ-2	one hundred and ten	two hundred and thirty	one hundred and ten	one hundred and forty	one hundred and thirty	1-3A	0.06A
LX3-4	LJ-4	one hundred and forty	two hundred and eighty-five	one hundred and ten	one hundred and sixty-eight	one hundred and thirty	1-3A	0.06A
LX3-7	LJ-7	one hundred and eighty-five	three hundred and ten	one hundred and ten	one hundred and eighty	one hundred and thirty	1-8A	0.06A

(2) The external insulation of LJ-2, LJ-4, and LJ-7 cable type zero sequence transformers of the same product is wrapped with insulation tape.

Figure 2 External dimensions of LJ series transformers

Table 2 Dimensions of LJ Series Transformers

model	A	H	Internal diameter d	Outer diameter D	Weight (kg)
LJ-2	one hundred and forty-five	two hundred and ninety-five	one hundred and ten	two hundred and thirty	twenty-one
LJ-4	two hundred and twenty	three hundred and fifty-five	one hundred and forty	two hundred and eighty-five	twenty-nine
LJ-7	two hundred and forty	three hundred and eighty-five	one hundred and eighty-five	three hundred and ten	thirty-one

(3) LX3- �� 75, LX3- �� 100, and LX3- �� 125 are thin cable type zero sequence transformers.
The transformer adopts resin casting for full sealing, which has the characteristics of good insulation performance, beautiful appearance, and easy installation. This type of transformer is used in conjunction with DD11/0.2 type relays, with a primary zero sequence current of 10A, a secondary current of 0.2A, and a secondary load of 10 ��.

Figure 3 LX series transformer external dimensions diagram three

Table 3 Dimensions of LX Series Transformers (III)

new model	old model	Inside d	External D	Thick M	mounting hole spacing	Hole center height r
LX3-��75	LJ-��75	seventy-five	one hundred and thirty-five	fifty-five	one hundred and ten	eighty-five
LX3-��100	LJ-��100	one hundred	one hundred and sixty	fifty-five	one hundred and ten	ninety-five
LX3-��125	LJ-��125	one hundred and twenty-five	one hundred and ninety-five	sixty-six	one hundred and ten	one hundred and twenty-five

(4) LXK - �� 100, LXK - �� 120 open-ended cable type zero sequence transformer.
The iron core of the zero sequence transformer is divided into two sides that can be folded, making it easy to install when cables have already been laid. The two sides of the transformer are resin cast, which has the characteristics of good insulation performance, beautiful appearance, and easy installation. This transformer is used in conjunction with DD11/60 type relays, with a primary zero sequence current of 3-5A, a secondary current of 0.06A, and a secondary load of 10 ��.

Figure 4 External dimensions of LXK series transformers

Table 4: Dimensions of LXK Series Transformers

appearance	LXK ��100	LXK ��120
Internal ��	one hundred	one hundred and twenty
External D	one hundred and ninety-five	two hundred and fifty
H	two hundred and twenty	two hundred and seventy-five
Y	one hundred and twenty-three	one hundred and fifty
M	eighty-five	one hundred

(5) LXM-1, LXM-2, LXM-3 busbar zero sequence transformers. This type of transformer is used in conjunction with DD11/60 type relays, with a primary zero sequence current of 2.4A, a secondary current of 0.06A, and a secondary load of 10 ��.

Figure 5 External dimensions of LXM series transformers

new model	old model	Copper quantity	rated current	Thermal stability current	dynamic stable current
LXM-1	LXM-1	1 piece	1750A	24kV	60kV
LXM-2	LXM-2	2 pieces and	3000A	48kV	120kV
LXM-3	LXM-3	3 pieces and	4000A	72kV	180kV

Please specify if there are any differences in zero sequence current and relay parameters among the above models of transformers.
(6) Neutral point grounded cable type zero sequence current transformer.
1) At present, the types of high current grounding and low current grounding for neutral points in China's 6 and 10kV power grids are gradually increasing. Therefore, the specifications of their zero sequence current transformers are as follows:
(a) 150/5A,200/5A�� Load 0.6 ��.
(b) 40/0.5A��75/0.5A��100/0.5A�� Load 13 ��. In addition, other specifications of zero sequence current transformers can be designed and manufactured according to user requirements.
2) Model meaning

3) The main technical data is shown in Table 6.
Table 6 Main Technical Data

model	inner diameter d	Outer diameter D	Thickness M	hole center High Y	mounting hole spacing	Current once	Current once	Secondary load
LXZ-��100	one hundred and ten	two hundred and thirty	one hundred and ten	one hundred and forty	one hundred and thirty	150A	5A	0.6��
LXZ-��145	one hundred and forty-five	two hundred and eighty-five	one hundred and ten	one hundred and sixty-eight	one hundred and thirty	150A	5A	0.6��
LXZ-��150	one hundred and fifty	two hundred and sixty	seventy	one hundred and sixty	one hundred and thirty	150A	5A	0.6��
LXZ-��185	one hundred and eighty-five	three hundred and ten	one hundred and ten	one hundred and eighty	one hundred and thirty	150A	5A	0.6��
LXZ-��200	two hundred	three hundred and twenty	seventy	one hundred and ninety	one hundred and thirty	150A	5A	0.6��

Figure 6 External dimensions of LXZ series transformers

LX3-2, LX3-4, LX3-7 are equivalent to LJ zero sequence current transformers

[zero-sequence current transformer]LBD,LCT-1/LKZB-0.5 Zero sequence current transformer

2026-6-15 19:52:37

Product Model:
LBD zero sequence current transformer (LCT, LKZB-0.5 zero sequence current transformer)
Main Features
1. Solved the problem that general zero sequence current transformers cannot be used in 1A and 2A systems.
2. This product has high precision, good linearity, reliable operation, and easy installation.
3. The exterior design adopts two types: circular and a combination of two semicircles, which are beautiful and reasonable, and have a novel structure.
kind
1�� Ordinary zero sequence current transformer:
Main technical indicators:
1. Scope of application: Power systems with all 400V-66KV cable feeders.
2. Zero sequence current: The input current on the primary side is 1-36A (customized for orders above 36A), and the output current on the secondary side is 20-300mA.
3. Grid frequency: 50Hz.
4. Secondary load resistance: �� 2.5 ��.
2�� Specially designed zero sequence current transformer:
In order to meet the needs of power grid expansion in the power industry, our company has successfully developed several high current zero sequence transformers to be used in conjunction with our MLN98 microcomputer line selection device. The system zero sequence currents are 50A-450A and 50A-900A, and the application range has significantly expanded.
3�� Large capacity zero sequence current transformer:
To adapt to neutral point low current grounding systems, our company has successfully developed various high current zero sequence transformers. The zero sequence current range of the system is 300A, 150A, 75A, the secondary current is 5A or 1A, and the capacities are 20KVA, 15KVA, 10KVA, and 5KVA, all of which can be customized for users.
Product standard:
Verified by the Quality Inspection and Testing Center for Automation Equipment of the Ministry of Electric Power Industry.
Normal usage conditions:
Environmental temperature: -20 �� -+50 ��, relative humidity:<90%, atmospheric pressure: 80Kpa -200Kpa.
Product model meaning:
The zero sequence current transformer
Overall dimensions:
From an inner diameter of 80 to 240mm, and can be customized according to user requirements for inner diameters above 200mm.

LBD, LCT-1/LKZB-0.5 zero sequence current transformer

[zero-sequence current transformer]LXK(C) series zero sequence current transformer

2026-6-15 19:52:28

The LXK series zero sequence current transformer is suitable for zero sequence overcurrent protection and small current grounding line selection devices in AC power systems, distribution lines, AC generators, motors and other electrical equipment. The aperture range for cable penetration is from 80mm to 240mm.

The LXK (C) series zero sequence current transformer uses imported high-quality silicon steel sheets and is made into a circular iron core through special processes, which has high accuracy and accuracy limit coefficient. The iron core and secondary winding are vacuum cast with high-quality epoxy resin in a flame-retardant plastic shell, which is moisture-proof, stable in performance, maintenance free, small in size, light in weight, and occupies small space.

The LXK series open type zero sequence current transformer consists of two semi-circular rings, which can be installed on connected cables, making it simple, fast, harmonious and beautiful. The LXK series through type zero sequence current transformer will be pre fixed on cable penetrations of electrical equipment such as ring network switchgear cabinets. During installation, the cable head will be made by threading the cable through the transformer.

The rated current, accuracy level, and rated load are shown in the following table:

LXK (C) series zero sequence current transformer

[zero-sequence current transformer]LXJK-120 type zero sequence transformer

2026-6-15 19:52:19

LXJK-120 Zero Sequence Transformer

[zero-sequence current transformer]LXK type low voltage zero sequence current transformer

2026-6-15 19:52:11

1. Overview:

The LXK type low-voltage zero sequence current transformer is used for grounding protection of generators, synchronous phase-shifters, or motors in small grounding current systems. The relay used in conjunction with this type of current transformer is DD-11/60 type. When there is a ground fault within the protection range, zero sequence current is generated in the secondary circuit of the transformer, causing the relay to operate.

2. Model meaning:
L X K �C ��80��100��120��

Current transformer can pass through cable diameter (mm)
Zero sequence opening and closing type

3. Structural features:

This type of zero sequence current transformer is an open type, and its iron core is divided into two sides that can be disassembled, making it easy to install when cables have already been laid. The two sides of the transformer are cast with resin, which has good insulation performance, beautiful appearance, and easy installation.

4. Technical parameters:

model	Diameter of penetrable cable (mm)	secondary circuit		Primary zero sequence current (A)	Secondary winding power frequency withstand voltage
		Secondary load (��)	Set current (A)
LXK-��80	eighty	ten	zero point zero six	3~5	3kV/1min
LXK-��100	one hundred
LXK-��120	one hundred and twenty

LXK type low-voltage zero sequence current transformer

[zero-sequence current transformer]LJZ1 type zero sequence current transformer

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LJZ1 type zero sequence current transformer

[zero-sequence current transformer]LJZ2-110 type zero sequence current transformer

2026-6-15 19:51:53

LJZ2-110 Zero Sequence Current Transformer

[zero-sequence current transformer]LMZC-0.5 type current transformer

2026-6-15 19:51:45

LMZC-0.5 type current transformer

[zero-sequence current transformer]LCT series zero sequence current transformer

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The LCT series zero sequence current transformer has the characteristics of high precision, good linearity, reliable operation, and easy installation. Especially, this type of transformer can also adapt to systems with zero sequence currents of 1A and 2A, which is not suitable for general zero transformers. The external design is a combination of two central circles, which is aesthetically pleasing and novel in structure. It is suitable for use in power supply systems in industries such as electricity, metallurgy, coal, petroleum, chemical, and building materials

Technical parameters of LCT series zero sequence current transformer

1. Usage environment
a. Environmental temperature: -20 ��~50 ��;
b. Relative humidity: �� 90%
c. Atmospheric pressure: 80kPa~200Kpa;
2. AC voltage: 66kV~4000kV;
3. Zero sequence current:
Primary side 1~36A (customized for 36A and above, secondary side 20~30mA)

Appearance and installation dimensions

LCT series zero sequence current transformer

[zero-sequence current transformer]LJ- �� 75 type zero sequence current transformer

2026-6-15 19:51:27

The LJ - �� 75 zero sequence current transformer is suitable for grounding protection of power cables in small grounding current systems indoors, with a rated frequency of 50HZ or 60HZ and a rated voltage of 35KV and below. Compared to this type of zero sequence electricity

Model meaning
LJ-��75
L-Current Transformer
J-For grounding protection
The upper limit value of the outer diameter of the three-phase cable with a diameter of 75

Structure Introduction
The iron core of this series of zero sequence current transformers is annular, and the secondary winding is uniformly wound on the iron core. The iron core is clamped with clamps, which are equipped with mounting holes.
Technical Specifications
The primary insulation of this series of zero sequence current transformers is guaranteed by cables, and the product only assesses the insulation performance of the secondary winding. The secondary winding can withstand a 3KV power frequency withstand voltage to ground.
The sensitivity of this series of zero sequence current transformers meets the requirements in the following table:

model	Connecting wire resistance ��	Relay starting current ��A��	sensitivity ��A��	Relay scale value ��A��	rated current ratio ��A��
LJ-��75	one	zero point one	6-10	0.1-0.2	30/1

Appearance and installation dimensions

The relay model used in conjunction with the current transformer is DL-11/0.2 type.

LJ - �� 75 type zero sequence current transformer

[zero-sequence current transformer]LJ series zero sequence current transformer

2026-6-15 19:51:19

The LJ series zero sequence current transformer is used for ground protection of generators or synchronous phase-shifters in 50Hz neutral point non effectively grounded systems.

The relay DD11/60 type is used for LJ series zero sequence current transformers. When there is a ground fault within the protection range, residual current is generated in the secondary circuit of the transformer. When the current reaches a certain value, the relay will operate.

Model number	LJ-2	LJ-4	LJ-7
Number of cable penetrable	1-2	3-4	5-7
secondary circuit
Secondary load (��)	ten	ten	ten
Set current (A)	zero point zero three	zero point zero three	zero point zero three
Sensitivity (A)	one point three	one point three	one point eight
Unbalanced voltage (mV)	forty	forty	thirty
Insulation level (KV)	0.5/2	0.5/2	0.5/2

Note: For cables with an outer diameter of less than 50mm, if it is greater than 50mm, a larger transformer must be used

Model number	A	B	H	��d	��D	Weight (kg)
LJ-2	one hundred and fifty	two hundred	two hundred and ninety-five	one hundred and eighteen	two hundred and thirty	twenty
LJ-4	two hundred and twenty	two hundred and eighty	three hundred and thirty-five	one hundred and forty-three	two hundred and eighty-five	twenty-nine point five
LJ-7	two hundred and twenty	three hundred	three hundred and seventy-five	one hundred and ninety-eight	three hundred and ten	thirty

LJ series zero sequence current transformer

[zero-sequence current transformer]LJM series zero sequence current transformer LJM-1 LJM-2 LJM-3

2026-6-15 19:51:10

The LJM type zero sequence current transformer is used for indoor devices with a frequency of 50Hz, 15kV and below for AC systems. It is used as a grounding protection for generators or synchronous phase-shifters in small grounding current systems. The relay used in conjunction with the transformer is the DDH/60 type. When there is a ground fault in the system circuit, zero sequence current is generated in the secondary circuit of the transformer to cause relay action.

Technical Specifications

Appearance and installation dimensions

LJM series zero sequence current transformer