Smart Lightning Arrester Leakage Current Sensor

Model:

HMJ1011-WBJ

Overview:

The HMJ1011-WBJ is a precision sensor designed to monitor leakage current and resistive current components of lightning arresters. By tracking these values, it can detect early aging or moisture issues in MOA varistors. It also features a lightning strike counter, offering high sensitivity and accuracy.

 

Features:

• Measures total current, resistive current, and lightning strike counts
• Supports both local pointer display and remote monitoring
• LoRa wireless communication, no wiring required
• Self-powered, ultra-low power design ensures long service life
• Pointer-type analog display for real-time on-site readings

 

Main Specifications:

Parameter	Specification
Total Current Range	100μA–5mA
Total Current Resolution	1μA
Total Current Accuracy	±(2% of reading + 5μA)
Resistive Current Range	10μA–2mA
Resistive Current Resolution	1μA
Resistive Current Accuracy	±(5% of reading + 2μA)
Protection Level	IP68
Communication Protocol	Wireless: LoRa 470/2.4G
	Wired (optional): RS485
Power Supply	Wireless: Self-powered
	Wired (optional): DC24V

Frequently Asked Questions about smart lightning arrester leakage current sensor

What is the smart lightning arrester leakage current sensor (HMJ1011-WBJ) used for?

The smart lightning arrester leakage current sensor — model HMJ1011-WBJ is designed for continuous online monitoring of metal-oxide surge arrester condition. It is deployed in substations, switching stations and transmission line towers, where it gives maintenance teams continuous or periodic visibility of insulation condition so that defects can be identified before they develop into unplanned outages.

What is the total current range of the HMJ1011-WBJ?

According to the published specification, the total current range is 100μA–5mA. This figure is measured under the reference conditions stated in the product datasheet; for project-specific acceptance criteria please refer to the type test report supplied with the quotation.

Why monitor resistive leakage current instead of total leakage current?

Total leakage current flowing through a metal-oxide surge arrester is dominated by the capacitive component, which changes very little as the valve blocks age. The resistive component is small but it is the part that increases when the blocks absorb moisture or deteriorate. By separating and tracking the resistive component (specified here as 10μA–2mA), the HMJ1011-WBJ detects arrester ageing at an early stage — long before the total current shows a meaningful change.

How is the smart lightning arrester leakage current sensor powered and how does it communicate?

The HMJ1011-WBJ uses the following interface configuration: communication is Wireless: LoRa 470/2.4G; power supply is Wireless: Self-powered; the enclosure is rated IP68. This allows the same device to be fitted in both retrofitted installations and new builds; the exact combination is confirmed at order stage against the site communication architecture.

Is installation possible without an outage?

In most cases yes. Because the smart lightning arrester leakage current sensor is installed on the equipment while it remains energised, the work is normally carried out as a live-line operation by qualified personnel following the site safety rules. Where a sensor must be coupled to an earthed screen, bonded connection or gas compartment, a short outage may be required — this is confirmed during the site survey.

Does HUWOR support OEM/ODM and what is the delivery lead time?

Yes. Zhuhai Huawang Technology Co., Ltd. supplies the smart lightning arrester leakage current sensor under its own brand and also supports OEM/ODM supply, including private labelling, custom firmware functions and integration with the customer’s monitoring platform. Standard units are typically quoted with a lead time confirmed at order stage depending on quantity and configuration; sample and pilot orders are supported.

Applications

The smart lightning arrester leakage current sensor is used for continuous online monitoring of metal-oxide surge arrester condition. Typical installation sites include substations, switching stations and transmission line towers. It is applied both on new assets, where the monitoring function is built into the asset from the start, and on existing assets where it is retrofitted to extend the information available to the maintenance team.

How it works

The instrument converts the physical quantity of interest into an electrical signal, conditions and digitises that signal in the field unit, and passes the result to the monitoring platform or to the operator. Condition assessment relies on the trend rather than on a single reading: the value recorded today is compared with the commissioning value and with the historical series for the same measurement point, and it is the direction and rate of change that indicate whether the asset is degrading.

Installation and commissioning

Installation follows three steps: a site survey to confirm the mounting position, the communication path and the power arrangement; mechanical fitting of the sensor or the use of the instrument on the test point; and finally commissioning, where the readings are verified against a reference and the alarm thresholds are set.

For this model the relevant interface conditions are: communication Wireless: LoRa 470/2.4G, power supply Wireless: Self-powered.

Standards and documentation

Type test reports, calibration certificates and installation documentation are provided with the supply. Where a project requires the equipment to be verified against a specific national or utility standard, the applicable clauses should be stated in the enquiry so that the test scope can be confirmed at quotation stage.