- A-B SF6
Overview of Transformer Iron Core Current Online Monitoring System
The HNP transformer iron core grounding current online monitoring system adopts electrical measuring method: without changing the original equipment wiring, the signal sampling point is selected at the transformer iron core grounding outlet, the grounding current value is measured directly with a high-sensitivity zero-flux current sensor which is made of a special coil, and the signal is digitalized locally and is uploaded to the upper-level controller through a communication cable to judge the deterioration of internal insulation. It is possible to find out faults such as dampening or damage of internal insulation, multi-point grounding of iron core, foreign matters in the box and deposition of oil sludge in the oil tank, so as to play the role of early warning of faults.
With DSP technology, the hardware platform has high integration, strong anti-interference capacity, high reliability and fast operational speed. With high-permeability iron core, the sensor has a very good linearity to detect small signals accurately. Meanwhile, complete shielding measures are taken to greatly reduce the influence caused by interference. The pre-amplification part adopts low-temperature drift and high-precision operational amplifier and high-precision resistor to guarantee the precision and stability of the analog amplification channel.
Current detection/display/alarm: The detection signal is triggered in real time, and the field host and the computer in the main control room display the current value status at the sensors on the transformer synchronously and dynamically, and when the current is more than 100mA (national standard value, which can be set by the users), the system displays "abnormal" reversely, otherwise, it displays "normal"; in case of "abnormal" condition, the system will send an alarm signal.
Self-check function: The sensor conducts real-time diagnosis, uploads the fault information and communication status dynamically and triggers the monitoring host to display such fault information and communication status, and in case of fault, the information of the faulty sensor will be displayed in the interface. A separate self-check and self-diagnosis module is designed in the internal hardware structure, and when any abnormality or abnormal running of the main system program is detected, it is reset automatically and the corresponding backup program is imported, so that the system can return to the normal work status in time.
Waterproof, rust-proof, moisture-proof and anti-interference: The system is of waterproof structure and adopts the water-crossing concave & convex groove design unique to the multi-protection chassis, and no leakage occurs at all. The enclosure is made of stainless steel, which can prevent rust and has no problem under sun exposure. Electromagnetic shielding is used for all parts to avoid the interference of strong electromagnetic field.
Working power supply
AC 220V±10%, 50/60Hz, about 5w
automatic current limiting
manual current limiting (optional)
Single / dual (optional)
Current measurement range
Alarm setting range
Settable within the full measuring range
1) Optoelectronic isolation relay output
2) SMS alarm module
Relay interface capacity
5A/240Vac or 28Vdc, one each for NC + NO
RS485 communication interface/GPRS/IEC61850
Transformer iron core / clamp online monitoring system
Transformer iron core online monitoring system
1# main transformer
2# main transformer
1# main transformer
2# main transforme
A-phase iron core grounding current
B-phase iron core grounding current
C-phase iron core grounding current
A-phase clamp grounding current
B-phase clamp grounding current
C-phase clamp grounding current