Two-in-One Partial Discharge Sensor

Model:
HMJ1010-AT

Product Overview:
The intelligent Two-in-One Partial Discharge Sensor integrates Ultrasonic (AA) and Transient Earth Voltage (TEV) detection technologies. It is widely used in substations, switching stations, and other power facilities for monitoring partial discharges in ring main units (RMUs), switchgears, and similar equipment. The sensor helps detect potential insulation defects early, ensuring the safety and reliability of power systems.

Key Features:

1、Multi-Parameter Detection:

Combines TEV and AA detection methods to capture both electrical and mechanical vibration signals of partial discharge. Through comprehensive multi-dimensional data analysis, it provides accurate assessments of insulation conditions and partial discharge severity.

2、Strong Anti-Interference Capability:

Designed with advanced filtering and shielding techniques to effectively suppress electromagnetic interference and noise. This ensures stable and reliable performance in complex power system environments.

3、Smart Diagnosis & Early Warning:

Equipped with intelligent algorithms and data analysis modules, the sensor processes large amounts of real-time data to automatically identify partial discharge characteristics and patterns. It performs fault diagnosis and issues early warnings based on preset thresholds and rules, helping prevent insulation failures.

4、Easy Installation:

The sensor supports magnetic or other easy-to-install mounting methods, allowing on-site installation and maintenance without powering down the equipment. This ensures non-invasive deployment and does not affect the normal operation or power supply of the grid.

 

Technical Specifications:

Item	Technical Data
TEV	Frequency Range: 1–100MHz
	Measurement Range: 0–70dB
AA	Resonant Frequency: 40kHz
	Measurement Range: -10–75dB
Communication	Wireless: LoRa; Wired: RS485
Power Supply	Wireless: Built-in Lithium Battery; Wired: DC24V
Operating Temp	-40°C to +85°C
Humidity	5%–95% RH

Frequently Asked Questions about two-in-one partial discharge sensor

What is the two-in-one partial discharge sensor (HMJ1010-AT) used for?

The two-in-one partial discharge sensor — model HMJ1010-AT is designed for continuous online partial discharge monitoring of HV switchgear and cables. It is deployed in HV switchgear, cable terminations, GIS and transformer bushings, where it gives maintenance teams continuous or periodic visibility of insulation condition so that defects can be identified before they develop into unplanned outages.

Which detection principle does this sensor use, and how do I choose?

Different partial discharge defects are best seen with different coupling methods. UHF sensors pick up electromagnetic waves emitted by discharge inside metal-enclosed equipment and give good immunity to corona from outside; HFCT sensors couple to the pulse current flowing on the earthing or cable screen and suit cable and transformer applications; contact ultrasonic and TEV sensors are used for surface and internal discharge in switchgear. The HMJ1010-AT listed here applies the principle best matched to its intended installation, and multi-function versions combine several principles in one housing where the defect type cannot be predicted in advance.

How is the two-in-one partial discharge sensor powered and how does it communicate?

The HMJ1010-AT uses the following interface configuration: communication is Wireless: LoRa; Wired: RS485; power supply is Wireless: Built-in Lithium Battery; Wired: DC24V. 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 two-in-one partial discharge 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 two-in-one partial discharge 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 two-in-one partial discharge sensor is used for continuous online partial discharge monitoring of HV switchgear and cables. Typical installation sites include HV switchgear, cable terminations, GIS and transformer bushings. 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; Wired: RS485, power supply Wireless: Built-in Lithium Battery; Wired: DC24V.

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.