Shanghai Huabang Industrial Business Network - Leakage relay

[Leakage relay]HLJ-��FS/LLJ-��FS series leakage relay

2026-6-17 18:01:49

HLJ - �� FS/LLJ - �� FS series leakage relay

[Leakage relay]CLJ3 series residual current operated relay

2026-6-14 11:06:39

The CLJ3 series residual current action relay is an AC type residual current relay, mainly used in distribution systems with AC 50Hz, rated working voltage of 690V and below, and neutral point directly grounded. It is combined with circuit breakers or contactors to form a combined residual current protector. Protectors can provide additional protection against potential fire hazards caused by long-term grounding faults that cannot be detected by overcurrent protection devices. The product complies with the standard GB/T22387 "Residual Current Operated Relays". The product has obtained the national mandatory product certification "CCC" certificate.

[Leakage relay]SRMJL-1 series phase amplitude leakage protection relay

2026-6-14 10:29:40

The SRMJL-1 series phase amplitude leakage protection relay is combined with AC contactors or circuit breakers to form a leakage protection device, which is suitable for low-voltage (380/220V) distribution systems with a neutral point directly grounded. Its main function is to provide indirect contact protection against fatal electric shock and improve the safe operation capability of the power grid. Due to the adoption of the new technology of phase and amplitude discrimination, insensitive phases and dead zones during electric shock are eliminated, and leakage and electric shock can be automatically distinguished. It also has various functions such as energy saving and noise reduction, making it particularly suitable for use in rural power grids with poor line conditions and three-phase imbalance.

characteristic
1. Distinguish phase and amplitude, with no action dead zone. In the case of unbalanced three-phase leakage, the sensitivity of each phase's electric shock action is consistent.
2. Automatically distinguish between leakage and electric shock, and can be put into operation in situations where the insulation level of the line is low and the leakage current is high.
3. Strong anti-interference ability, no misoperation under interference conditions such as lightning, power grid harmonics, and instantaneous overcurrent of the line.
4. When the leakage of the circuit suddenly decreases, it does not operate and has a high commissioning rate.
5. It has a power test function when turned on, and can automatically reclose within 20-30 seconds after tripping, which is safe and labor-saving.
6. Energy saving silent operation, the working voltage of the matched contactor coil can be used at 380V or 220V, and long-term operation does not burn the coil. The active power saving rate is 85%.
7. Zero sequence transformers are interchangeable and universal.
8. Adjustable leakage current: The leakage current values of 300 and 500mA can be adjusted, which significantly improves the operation rate and safety, and has strong adaptability.
9. Instrument display leakage value: The instrument automatically displays the leakage value of the circuit, making it easy to check the condition of the circuit at a glance.

Main technical parameters

technical parameters	model
technical parameters	SRMJL-1	SRMJL-1/A	SRMJL-1/B	SRMJL-1/D
rated voltage	380/220V	380/220V	380/220V	380/220V
rated frequency	50Hz	50Hz	50Hz	50Hz
rated current	250A	400A	630A	Below 1000A
Rated leakage action current	300mA/500mA adjustable	300mA/500mA adjustable	500mA	300mA/500mA adjustable (Below 4000)	500mA ��630A-1000A��
Rated leakage non operating current	��150mA/250mA	��150mA/250mA	250mA	��150mA/250mA	250mA
Rated sudden change leakage action value	75mA	75mA	75mA	75mA
Rated sudden change leakage non action value	38mA	38mA	38mA	38mA
Rated breaking time	��0.2s	��0.2s	��0.2s	��0.2s
Sudden decrease in leakage and no action value	��150mA/250mA	��150mA/250mA	250mA	��150mA/250mA
Delay reclosing	20-30s	20-30s	20-30s	20-30s
Classification of Action Characteristics	AC type	AC type	AC type	AC type
Rated fuse capacity	5A	5A	5A	5A
Rated short-time withstand current	3000A	3000A	3000A	3000A
Energy saving effect	Active power saving rate>85% Reactive power saving rate>5%	-	-	-

Specifications and external dimensions

model	type	Matching contactor and rated current range	Dimensions (mm)	number of packages
SRMJL-1	Standard energy-saving type (small ring diameter 45mm)	CJ type (ordinary type) is suitable for 63A-250A (relay required for 40A and below)	205×110×72	6 pieces
SRMJL-1/A	No energy-saving type (middle ring diameter 45mm)	CJ type is suitable for 400A and below	205×110×72	6 pieces
SRMJL-1/B	No energy-saving type (large ring diameter 85mm)	CJ type is suitable for 630A and below	205×110×72	4 pieces
SRMJL-1/D	Various rings	Suitable for SRM and DW type circuit breakers Suitable for 1000A and below	205×110×72

[Leakage relay]BLD-20 High Voltage Leakage Protection Relay

2026-6-14 10:00:45

The BLD-20 high-voltage leakage protection relay (hereinafter referred to as the relay) has a power directional leakage protection function. It can be used in conjunction with vacuum low oil and SF6 mining general distribution switches (devices) or vacuum circuit breakers for selective protection against leakage (or grounding) in 3-10KV medium point ungrounded systems of the power supply system.

characteristic
Adopting the power directional principle, it operates reliably. The internal circuit components have the advantages of easy selection, high sensitivity, strong selectivity, and stable performance. Choose a small sealed relay as the fault memory component, with power indication and a light display after the fault, to quickly and accurately diagnose the fault. Install using the latest guide rails or fixed installation. The test and reset buttons can be externally connected or not, making them very convenient to use.

Usage conditions of BLD-20 high-voltage leakage protection relay
1. The altitude shall not exceed 3000 meters.
2. The ambient temperature should not exceed+40 �� and should not be lower than -20 ��.
3. The relative temperature of the surrounding air is not greater than 95%. (When the ambient temperature is+25 ��).
4. Without explosion-proof casing, it cannot be used in environments with explosive hazards.
5. In a gas environment that does not damage metals or corrode insulation.
6. A place without dripping or water intrusion.

Main technical data
1. The primary zero sequence current of the leakage protection sensitivity relay is 0 1A. The secondary zero sequence voltage is 3V ± 0.4.
2. Primary zero sequence current grading: 0.1, 0.3, 0.5, 1.0, 3.0, 6.0 (A) with an error not exceeding ± 10%.
3. Protection action time: 0.1, 0.5, 1.0, 1.5, 2.0, 5.0 (S) with an error not exceeding ± 10%.
4. Rated power supply voltage: 100V, 50Hz. This device can operate normally within the range of 100V ± 20%.
5. Output contact life: 115VAC × 1A (resistive load) 100000 times. 28VDC × 2A (resistive load) 100000 times.

Working principle of BLD-20 high-voltage leakage protection relay
Leakage protection consists of zero sequence current circuit, zero sequence voltage circuit, phase comparison, time division, and relay locking unit. When a leakage or grounding occurs in the circuit, zero sequence voltage exists simultaneously. The phase comparison is carried out through the current circuit and voltage circuit respectively, and then divided into different time intervals to activate the relay and display the indicator light.

Structural appearance
1. This protective device uses an ABS plastic shell, and its appearance and installation dimensions are shown in Figure 1.
2. Dimensions: 90 × 116 × 50mm.
3. Net weight: �� 0.5Kg.

Inspection before installation and use
1. Appearance inspection: Check whether the relay model and accessories are complete, and the appearance should have no obvious damage or deformation. The indicator lights should be complete and securely fastened.
2. Electrical performance inspection shall be conducted according to BLD-20 external wiring diagram 2 for wiring. Use the test button for testing, the unit should operate normally, and the indicator light should display a light. Random inspection of all major technical data should meet the requirements.

Installation, use and maintenance
1. Each unit should be positioned as required.
2. After installation, the test button on the power distribution device must be powered on for testing, and the action should be normal.
3. Installation and use of zero sequence current transformer: Zero sequence current transformer is a key component of leakage protection. The terminal face is facing the power supply side of the busbar, with K connected to pin 8 of the protection device, S connected to pin 9 of the protection device, and D connected to pin 10 of the protection device. It cannot be reversed.
4. It is strictly prohibited to use a megohmmeter to test the circuits inside this device.
5. When repairing welded components, a soldering iron with a power of less than 45W should be used to prevent component burnout.
6. To replace the semiconductor components on this device, it must be tested and screened before use.
7. In order to keep the protective device in normal working condition, regular tests and inspections should be conducted.

[Leakage relay]LJM series leakage relay LJM-II/400 250 630 330 500

2026-6-13 19:39:09

JD27, LJM-II series leakage pulse relay

LJM series leakage relay

[Leakage relay]JDL-I type leakage relay

2026-6-13 19:39:01

The JDL-I leakage relay is combined with an AC contactor or circuit breaker to form a leakage protection device. Due to the use of the new technology of phase and amplitude detection, it eliminates the insensitivity and dead zone during electric shock, automatically distinguishes between leakage and electric shock, and has various functions such as energy saving and noise reduction.

The product complies with standards such as GB6829-95 and JB8756-98, and is recommended for the national "two networks" renovation.

Scope of application

Suitable for low voltage (380/220V) distribution systems with a neutral point directly grounded, the main function is to provide indirect contact protection against fatal electric shock to individuals. Especially suitable for use in power grids with poor line conditions and unbalanced three-phase leakage, to improve the safe operation capability of the power grid.

JDL-I type leakage relay

[Leakage relay]JD27,LJM-II series leakage pulse relay

2026-6-13 19:17:20

JD27, LJM-II series leakage pulse relay

[Leakage relay]JD3,JD8 type leakage relay

2026-6-13 19:17:02

Structure and working principle:
JD3 is an electronic current operated leakage relay, mainly composed of zero sequence current transformers, electronic circuits, test circuits, and small relays. The working principle is as follows:
As shown in the figure, when ground leakage occurs in the circuit passing through the zero sequence current transformer, iA+iB+iC+iN �� 0. The auxiliary side of the zero sequence current transformer generates an induction signal, which is processed by the electronic circuit. When the leakage current reaches the operating value, the thyristor conducts the small relay to close, and uses normally open and normally closed contacts to control the main line relay or contactor to disconnect and cut off the faulty line.
The test circuit is composed of resistor R5, button AN1, and wiring. When button AN is pressed, a current flows through the transformer, which is equivalent to leakage in the main circuit. The leakage relay should operate.

1�� The JD3-FS series leakage device is suitable for AC voltage up to 660V, frequency of 50Hz, current up to 630A and below, in transformer neutral grounding circuits. Leakage relays can be combined with circuit breakers, AC contactors, magnetic starters, etc. with shunt release or voltage loss release to form leakage protection devices for leakage and electric shock protection. They can also be combined with various sound and light indicators such as buzzers and signal lights to form leakage alarm devices. The action time of the leakage relay is divided into fast type and delay type, and when used together, it can provide graded selective protection for lines and branches. It is an improved model of JD3. This relay can completely replace the JD3 series leakage relay of the past.

rated voltage	Diameter of transformer through-hole �� (mm)				Rated leakage current (mA)	Rated leakage non operating current (mA)	Action time (s)		Rated control capacity
	And maximum rated current reference value (A)						Quick type	Slo-Blo
660/380	25/100	45/200	75/400	100/630	100 or user-defined	50 or user-defined	��0.1	0.2,0.4 0.8,1 1.5,2	~220V 3A

JD3 and JD8 leakage relays