HF-T-605 Transformer Core Clamp Earth Current Monitoring

Product Description

The Transformer Core Clamp Earth Current Monitoring Device is specialized intelligent online equipment for power transformer core and clamp condition monitoring, ensuring the safe operation of transformer internal magnetic circuits. Adopting high-precision through-core current sensors, it real-timely collects core and clamp grounding leakage current data to accurately detect early faults such as core multi-point grounding, insulation dampening and suspended metal foreign matters. It effectively compensates for the defect of traditional offline preventive tests that fail to monitor transformer core conditions in real time.

Main Product Features

Ultra-high Precision Weak Signal Capture

Adopting zero-flux through-core current sensors with a maximum current resolution of 10 μA, it precisely captures tiny grounding currents at milliampere and even microampere levels, delivering reliable data support for diagnosis of latent early faults.

Fully Non-intrusive Live-line Installation

Featuring a split structure, the sensor is directly sleeved onto the grounding downlead of the transformer iron core. Installation requires no disconnection of the grounding loop or equipment power outage, without altering the original grounding structure of the transformer or interfering with normal equipment operation.

Powerful On-site Anti-interference Performance

The sensor adopts a three-layer shielding structure paired with an adaptive digital filtering algorithm, which effectively isolates intense on-site electromagnetic interference in substations and ensures stable and reliable measurement data under complex working conditions, with a false alarm rate far below the industry average.

Wide Measuring Range with Consistent High Precision

The measurement range spans 0~10 A. It accurately monitors microampere-to-milliampere weak currents during normal operation while completely recording ampere-level heavy currents generated during multi-point grounding faults, realizing blind-spot-free monitoring across all operating conditions.

Long-term Stable Operation in Extreme Environments

The whole unit is built with industrial-grade electronic components and a high-protection enclosure, capable of stable operation within a wide temperature range of -30℃ to 50℃. It supports outdoor wall-mounted installation with rainproof, dustproof and anti-corrosion properties, adapting to harsh field conditions such as plateaus, frigid zones and high-humidity areas.

Maintenance-free & Long-lifespan Design

The hardware features a solid-state structure with no moving parts. Full-range calibration is completed before factory delivery, eliminating the need for factory recalibration during long-term operation. Its Mean Time Between Failures (MTBF) exceeds 50,000 hours, drastically reducing post-operation maintenance workload.

Core Functions

1. 24/7 Real-time Online Monitoring Continuously collects key parameters including RMS value, peak value and phase of grounding current of iron cores and clamps, displays real-time dynamic current variation trends, and tracks the health status of the transformer core.
2. Intelligent Identification of Multi-point Grounding Faults Through analysis of current amplitude mutation and harmonic feature extraction, it automatically detects two-point and multi-point grounding faults of the iron core, differentiates normal unbalanced current from abnormal fault current, and avoids missed judgments and misjudgments caused by traditional manual inspections.
3. Trend Tracking of Insulation Dampening Long-term monitoring of slow current growth enables early detection of insulation dampening weeks in advance at the initial stage of insulation deterioration, issuing early warnings and reserving sufficient response time for maintenance teams.
4. Multi-level Customizable Early Warning Mechanism Users may define multi-stage alarm thresholds. Once the current exceeds the preset value, local audible and visual alarms as well as remote message push are triggered automatically, with complete waveform data recorded at abnormal moments to facilitate fault tracing and analysis.
5. Full-cycle Data Storage & Analysis Built-in large-capacity storage supports archiving of historical monitoring data for more than 3 years. The system automatically generates daily, monthly and annual current trend curves to intuitively reflect long-term degradation patterns of the transformer core.
6. Multi-protocol Remote Transmission & Platform Interconnection Standard RS485 interface with embedded Modbus protocol is equipped. It also supports multiple power communication protocols including IEC 61850, IEC 103 and IEC 104, enabling seamless connection to substation integrated automation systems and remote operation & maintenance platforms.
7. Device Self-diagnosis The unit continuously diagnoses its own hardware status and automatically alerts users to faults such as sensor disconnection, communication interruption and power supply anomaly. Abnormality in a single channel will not affect monitoring of other measuring points, guaranteeing overall system reliability.

Product Technical Specification Table

Product Application

Hub Substation Main Transformer Safety Protection

Real-time monitoring for 110kV+ main transformers, early warning of multi-point grounding faults to avoid core overheating and insulation damage, guaranteeing grid stability.

New Energy Boost Station Unmanned Monitoring

Suits wind and PV remote booster stations, enables unattended remote monitoring to detect transformer core faults, easing the shortage of on-site maintenance staff.

Aging Transformer Status Assessment

Long-term online monitoring for over-aged transformers instead of regular power-off inspections, rationalizes load allocation and extends equipment service life safely.

Industrial Key Transformer Protection

24h monitoring for transformers in petrochemical, metallurgy and rail sectors, averting unexpected production halts and economic losses from sudden core failures.

Fault Backtracking & Analysis Assistance

Stores full-cycle historical current data to reproduce fault development, providing key evidence for troubleshooting and equipment improvement.

Smart Grid Condition-Based Maintenance

Delivers quantitative operational data to shift maintenance from regular outage inspections to condition-based maintenance, lowering O&M expenses effectively.

Installation Instructions

1. On-site Survey & Planning Field technicians arrive in advance to confirm the position of grounding downleads for transformer iron cores and clamps, determine installation positions of sensors and monitoring hosts according to site layout, and formulate a live-line installation scheme without interrupting normal transformer operation.
2. Sensor Deployment Fit the through-core current sensor directly onto the core grounding downlead with no disconnection of the original grounding loop. Secure the sensor and complete shielding protection, keeping it away from strong electromagnetic interference sources.
3. Monitoring Host Installation Wall-mount the main unit beside the control cabinet or outdoor pole near the transformer in a well-ventilated and dry location accessible for inspection and operation, complying with IP54 installation requirements.
4. Wiring & Commissioning Connect the sensor and main unit with shielded cables, switch on the power supply and perform signal verification, set current alarm thresholds matching on-site working conditions, and finish calibration of signal acquisition accuracy.
5. Communication Interconnection Lay communication cables, complete debugging for connection with local monitoring backends or remote O&M platforms, and verify normal remote data transmission and alarm push functions.
6. Acceptance & Handover Train maintenance staff on device operation and alarm disposal procedures, deliver complete installation documents and operation manuals, and finalize project acceptance and handover.

Why Choose Us

In-house R&D & Full-industry-chain Technical Edge

We are a professional power monitoring equipment manufacturer with independent R&D capabilities, mastering core technologies including high-precision zero-flux sensors and digital anti-interference algorithms instead of merely assembling and OEM products. Customized solutions can be rapidly tailored to diverse on-site operating conditions.

Strict Industry Quality Control

All products have passed full-type tests issued by national-level power equipment testing institutions. Every unit undergoes 72-hour high-temperature aging, full-range accuracy calibration and strong electromagnetic interference testing before delivery to guarantee stable and reliable performance.

Proven Mass On-site Application

Our products have been running steadily in hundreds of substation projects nationwide. Practical cases verify its capability to capture early core grounding risks accurately and warn of major equipment faults multiple times, helping clients avoid power outages and economic losses worth millions.

Optimized Installation & O&M Experience

The fully non-intrusive live-line installation requires no power cut and can be deployed within several hours. Built-in self-diagnosis minimizes routine maintenance, significantly lowering construction and post-operation costs.

Open & Compatible System Architecture

All mainstream power communication protocols are supported for seamless integration with existing substation automation systems and intelligent O&M platforms without system replacement or complex secondary development, eliminating data silos between different devices.

Localized Rapid After-sales Support

A comprehensive service network is established in Baoding, Hebei and surrounding areas. We promise 24-hour remote technical response and on-site technical support within 48 hours, providing full-lifecycle localized services including installation guidance, operational training and periodic on-site inspections.

FAQ

Q1: Is disconnection of the transformer grounding downlead required during installation? Will it compromise equipment safety?

A1: No disconnection is needed at all. The openable through-core sensor is sleeved directly over the grounding downlead without breaking the original grounding circuit. The grounding reliability of the transformer remains unchanged, posing zero safety risks to equipment operation.

Q2: Substations suffer severe electromagnetic interference; will measurement data be inaccurate or trigger frequent false alarms?

A2: This issue is eliminated. The three-layer shielding sensor plus adaptive digital filtering algorithm effectively suppresses strong on-site electromagnetic interference and ensures stable measuring precision. Verified by hundreds of field projects, its false alarm rate is far below the industry average.

Q3: Can the measuring range cover heavy fault currents?

A3: Fully capable. The standard measuring range is 0~10 A with a 10-fold overload capacity. It captures microampere weak currents under normal operation and records ampere-level fault currents during multi-point grounding, achieving full-coverage monitoring with no blind spots.

Q4: Does the equipment require periodic calibration and maintenance?

A4: The solid-state hardware contains no moving parts and is fully calibrated before factory shipment. No factory recalibration is required within 5 years under standard operating conditions; only annual routine inspection is recommended, resulting in minimal maintenance workload.

Q5: Can the device connect directly to our existing substation monitoring system?

A5: Fully compatible. Standard RS485 with Modbus is equipped, alongside support for IEC 61850, IEC 103, IEC 104 and other mainstream power protocols. Seamless access to most widely used power monitoring platforms is available without complicated secondary development.

Q6: Can the unit withstand harsh weather for outdoor installation?

A6: Yes. The main unit reaches IP54 ingress protection with a rainproof, dustproof and anti-corrosion metal enclosure. It operates reliably outdoors from -30℃ to 50℃ and withstands harsh weather such as heavy rain and sandstorms.