Grounding current of transformer core

By using a through type current transformer to isolate and transform into a small signal, the signal is processed through signal conversion, filtering, and amplification circuits, and then converted into a digital signal by an analog-to-digital converter. The microprocessor obtains the grounding current of the iron core through digital filtering and operation; The local display interface can display real-time grounding current, and has LED indication when it exceeds the alarm limit; The device can communicate in real-time with backend systems such as status monitoring systems through isolated RS485/CAN/GSM/GPRS communication interfaces (selected at the time of ordering).

The device has a current limiting resistor switching control unit interface. When the current exceeds the set limit, the current limiting resistor (4-speed resistance) is automatically switched in step by step to reduce the grounding current as an emergency measure. When the current is below the limit, the current limiting resistor is automatically cut off.

Grounding current of transformer core

Features

The main functions of the online monitoring device are as follows:

Real time monitoring

Using a 5-digit digital tube to display real-time grounding current locally, with various status indicators for power supply, operation, communication, and alarm;

● It has multiple communication interfaces such as RS485/CAN/GSM/GPRS, which can achieve regular active data upload or request response upload; Can be connected to the background of the status monitoring system or run independently, and regularly send data to the operation and maintenance management personnel through SMS;

● Two levels of alarm limits (warning limit and alarm limit) can be set. When the current exceeds the warning limit, data is actively uploaded through the communication interface. When the alarm limit is exceeded, the device will emit a local light alarm and communicate the alarm;

Equipped with a current limiting resistor switching unit interface, it automatically limits and alarms the grounding current of the iron core;

The device has internal non-volatile storage space, and data is not lost when power is turned off;

The device has self diagnosis and self recovery functions, and alarms when the device is abnormal or communication is abnormal.

The online monitoring device has stable performance, powerful functions, and the following technical characteristics:

Accurate and reliable monitoring data

The device adopts specially designed current transformers, high-precision analog circuits, and advanced digital signal processing technology, with a wide measurement range (1mA~30A), high accuracy (± 1%), and good anti-interference performance.

● Flexible application configuration

The device has multiple communication interfaces, which can be configured to connect to the comprehensive monitoring system of electrical equipment, or can be independently configured to achieve monitoring through GSM SMS.

● Easy installation and maintenance

The device body and current transformer adopt a separate design, and the fixture allows the current transformer to be flexibly installed on the iron core grounding lead. The device body can be flexibly installed in different positions according to the on-site situation;

The device has a complete self checking function, which can timely determine the status of the device and give an alarm;

Installation and maintenance of all components, including sensors (bypass iron core grounding down conductors), can be carried out without affecting the operation of the transformer.

● Safe and reliable

The through type current transformer does not damage the grounding lead wire and has no impact on the safe operation of the transformer;

All components are produced according to industrial standards and have good resistance to electromagnetic shock and temperature fluctuations;

The device adopts a fully sealed design, which has functions such as anti-corrosion, windproof, dustproof, and electromagnetic interference prevention, and can adapt to harsh outdoor operating environments.