Transformer Bushing Monitoring System for Continuous Insulation Health Monitoring
Our online bushing monitoring system tracks total current, capacitance, dielectric loss and partial discharge on high-voltage transformer bushings around the clock — turning bushing insulation health, condition and status into live, actionable data instead of a once-a-year offline test result.
- Continuous capacitance, dielectric loss, leakage current and PD monitoring on live bushings
- IN-205B model series — insulation-only, PD-only, or fully integrated configurations
- Modbus / DL/T860 output for direct SCADA and substation automation integration
What Is a Transformer Bushing Monitoring System?
A transformer bushing monitoring system is an online monitoring platform used for insulation condition monitoring of high-voltage transformer bushings. It continuously measures total current, capacitance, dielectric loss and — when configured — partial discharge, helping identify insulation aging, moisture ingress, abnormal leakage current and developing insulation defects before they progress into a bushing failure.
- Suitable for power transformers, substation transformers, generator step-up transformers and other capacitive high-voltage equipment
- Configurable as an insulation monitoring system, a partial discharge monitoring system, or an integrated bushing monitoring solution
- Provides online data, alarm thresholds and historical trend records for condition-based maintenance
Why Bushing Condition Needs Continuous Monitoring
Power transformer bushings sit under high voltage stress for years at a stretch. Because capacitance, dielectric loss, leakage current and partial discharge activity all change gradually as insulation ages, a once-a-year offline test is often too infrequent to catch a developing defect before it turns into an unplanned outage.
- Capacitance and dielectric loss shifts often develop between scheduled offline test dates
- Moisture ingress, contamination and thermal stress accelerate bushing insulation aging
- Leakage current abnormalities can appear well before a bushing shows a visible fault
- An unmonitored bushing failure carries some of the highest unplanned-outage risk on a transformer
What the Bushing Monitoring System Measures
Each monitored parameter maps to a specific bushing insulation health question, so the data can be used directly for condition-based maintenance decisions rather than just raw readings.
| Monitoring Purpose | Measured Condition | Maintenance Value |
|---|---|---|
| Insulation condition | Capacitance and dielectric loss change | Supports early insulation aging warning |
| Leakage current status | Total current and current variation | Helps identify abnormal bushing operating condition |
| Partial discharge activity | PD signal and discharge trend | Provides warning for developing insulation defects |
| Remote asset monitoring | Online data, alarms and historical trends | Improves transformer condition monitoring workflow |
Choose an Insulation, PD, or Integrated Configuration
The bushing monitoring system is built on the IN-205B platform and configured according to the monitoring function your project needs.
Bushing Insulation Online Monitoring
Total current, capacitance and dielectric loss monitoring — the base configuration for continuous bushing insulation condition tracking.
Insulation + Partial Discharge Integrated Monitoring
Combines bushing insulation parameters with partial discharge sensing in a single online monitoring configuration — the recommended choice when both data sets are needed.
Bushing Partial Discharge Online Monitoring
Dedicated partial discharge monitoring for transformer bushings, for projects that already track insulation parameters separately.
How Online Bushing Monitoring Works
Signal Acquisition
Sensors tap the bushing test terminal or grounding path to capture total current, capacitance and dielectric loss signals.
PD Sensing (Optional)
Where configured, partial discharge sensors capture discharge pulses related to bushing insulation defects in parallel.
Trend Processing
The monitoring host calculates capacitance and dielectric loss values, checks measurement repeatability, and builds a trend history.
Alarm & SCADA Output
Threshold alarms and trend data are output via Modbus or DL/T860 to substation automation and SCADA platforms.
What a Bushing Monitoring System Includes
A complete transformer bushing monitoring system pairs sensing hardware at the bushing with a monitoring host and a communication interface, so insulation data flows straight into your existing monitoring workflow.
- Bushing-side sensing connection at the test terminal or grounding path
- IN-205B series monitoring host — insulation, PD, or integrated signal processing
- Onboard alarm thresholds with local display and historical trend storage
- Modbus / DL/T860 output to SCADA, substation automation or asset platforms
Installation Options
- Standard 19-inch rack-mounted type — IP30 protection
- Wall-mounted outdoor type — IP55 protection
Transformer Bushing Monitoring System Specifications
Standard IN-205B series specifications — exact configuration is confirmed per project based on bushing type and monitoring function.
| Specification Item | Standard / Optional Configuration |
|---|---|
| Typical model | IN-205B series |
| Monitoring object | Transformer bushing insulation and partial discharge condition |
| Monitoring parameters | Total current, capacitance, dielectric loss, partial discharge |
| Total current measurement range | 2mA to 1000mA |
| Total current measurement accuracy | ±(standard reading 1% + 0.1mA) |
| Capacitance measurement range | 100pF to 50000pF |
| Capacitance measurement accuracy | ±(standard reading 1% + 1pF) |
| Dielectric loss measurement range | 0.001 to 0.3 |
| Dielectric loss measurement accuracy | ±(standard reading 1% + 0.001) |
| Measurement repeatability | <0.2% |
| Working power supply | AC220V ±10% |
| Communication protocol | Modbus, DL/T860 |
| Ambient temperature | -40°C to +70°C |
| Ambient humidity | 0 to 95%, non-condensing |
| Protection rating | Standard 19-inch rack type IP30; wall-mounted type IP55 |
| Installation type | Rack-mounted or wall-mounted configuration |
Communication for Bushing Condition Monitoring Platforms
Monitoring data, alarm status and trend information can be transmitted directly into substation automation systems, transformer monitoring platforms or SCADA.
| Communication Item | Function | Typical Use |
|---|---|---|
| Modbus | Transfers monitoring data and status information | SCADA, local monitoring system or industrial gateway |
| DL/T860 | Supports substation automation communication requirements | Substation monitoring and protection platform integration |
| Alarm output | Provides warning when monitored values exceed preset thresholds | Operation room, maintenance system or transformer control cabinet |
| Historical trend data | Records measurement changes for condition review | Bushing condition assessment and maintenance planning |
Where Bushing Monitoring Is Applied
| Application | Monitoring Need | System Value |
|---|---|---|
| Power transformer bushing | Online insulation and leakage current monitoring | Early warning for bushing insulation deterioration |
| High-voltage substation | Continuous monitoring of critical capacitive equipment | Improves asset visibility and maintenance response |
| Generator step-up transformer | Bushing condition tracking under high-load operation | Supports reliability of power generation assets |
| Industrial transformer | Monitoring for important production power supply equipment | Reduces risk of unplanned outage |
| Instrument transformer or surge arrester | Capacitive equipment insulation condition monitoring | Extends monitoring coverage beyond transformer bushings |
Selection is based on transformer type, bushing quantity, monitoring function, installation method and communication requirement — our engineering team can confirm a configuration matched to your equipment.
Complete Transformer Online Monitoring Solutions
Bushing monitoring covers one insulation path on the transformer. Explore the rest of our transformer monitoring solutions to build full asset health and condition coverage.
Transformer Monitoring
Our overall transformer online monitoring solution, combining temperature, DGA, PD, bushing and OLTC data into one condition monitoring view.
Partial Discharge Monitoring
UHF, HFCT and ultrasonic PD sensing across the transformer, pairing naturally with bushing-level discharge monitoring.
Transformer DGA Monitoring
Continuous fault-gas trending in transformer oil, useful for confirming whether bushing insulation issues are generating fault gases.
OLTC Monitoring
Tap-changer current, temperature, vibration, torque and position monitoring, for full electrical asset health coverage.
Fiber Optic Temperature Monitoring
Direct winding hot-spot temperature measurement, adding a thermal-stress data layer alongside bushing insulation status.
Transformer Temperature Monitoring
Online winding and top-oil temperature monitoring, complementing bushing and insulation condition data.
Bushing & Related Condition Monitoring Products
Our bushing monitoring hardware is factory direct and in-house engineered, and pairs naturally with our PD, OLTC and DGA monitoring products for complete transformer condition coverage.
Transformer Bushing Monitoring System
Model options from IN-205B insulation monitoring up to the IN-205B3 integrated bushing insulation and partial discharge configuration.
Bushing Monitoring System
A general-purpose bushing condition monitoring platform covering capacitance, dielectric loss and leakage current.
Partial Discharge Online Monitoring System
UHF, HFCT and ultrasonic PD sensing, cross-checked with bushing insulation data for a fuller diagnostic picture.
Online DGA Monitoring System
Continuous fault-gas trending for transformer oil, useful when bushing insulation issues need to be cross-checked against oil chemistry.
Transformer OLTC Online Monitoring System
Tracks tap-changer current, temperature, vibration, torque and position for complete electrical asset condition monitoring.
Fiber Optic Temperature Measurement System
Fluorescent fiber optic sensing for direct winding hot-spot temperature, complementing bushing insulation status data.
Bushing Monitoring, Engineered and Customized In-House
We design and manufacture our bushing monitoring hardware end to end — from the sensing connection to the IN-205B monitoring host — giving us the flexibility to tailor a configuration to your bushing type, voltage class, and plant-wide condition monitoring requirements.
- In-house R&D and manufacturing of bushing insulation and PD monitoring hardware
- Configurations tailored to voltage class, monitoring function and installation type
- Rack-mounted or wall-mounted enclosure options for indoor or outdoor environments
- Engineering support from initial consultation through commissioning
How to Select a Transformer Bushing Monitor
Selection should be based on bushing type, monitoring objective, installation method and required communication interface.
| Selection Item | What to Confirm |
|---|---|
| Transformer type | Power transformer, generator transformer, industrial transformer or other high-voltage equipment |
| Bushing quantity | Number of bushings and phases to be monitored |
| Monitoring function | Insulation monitoring, partial discharge monitoring or integrated monitoring |
| Measured parameters | Total current, capacitance, dielectric loss and PD monitoring requirement |
| Installation method | 19-inch rack installation or wall-mounted outdoor installation |
| Communication requirement | Modbus, DL/T860, SCADA or local monitoring platform connection |
| Site environment | Indoor cabinet, outdoor substation, ambient temperature and humidity condition |
Bushing Monitoring FAQ
What is a transformer bushing monitoring system?
A transformer bushing monitoring system is an online monitoring device used to monitor the insulation condition of transformer bushings through parameters such as total current, capacitance, dielectric loss and partial discharge.
Why is transformer bushing monitoring important?
Transformer bushings are critical high-voltage insulation components. Abnormal capacitance, dielectric loss, leakage current or partial discharge activity may indicate insulation deterioration and should be monitored for early warning.
What does the system monitor?
The system can monitor total current, capacitance, dielectric loss and partial discharge depending on the selected model and project configuration.
Can the system monitor partial discharge?
Yes. Partial discharge monitoring can be selected as an independent function (IN-205B2) or integrated with bushing insulation monitoring (IN-205B3).
Can the bushing monitoring system connect to SCADA?
Yes. The system supports communication protocols such as Modbus and DL/T860 for integration with substation monitoring systems or SCADA platforms.
What installation types are available?
The system can be configured as a standard 19-inch rack-mounted type (IP30) or a wall-mounted outdoor type (IP55) according to the installation environment.
What is the difference between online bushing monitoring and offline testing?
Offline testing gives a result at one point in time, usually during a scheduled maintenance window. Online bushing monitoring runs continuously while the transformer stays in service, tracking capacitance, dielectric loss and current trends instead of a single snapshot.
Does bushing monitoring relate to dissolved gas analysis (DGA)?
The two are complementary: bushing monitoring tracks the insulation and discharge condition of the bushing itself, while DGA measures fault gases dissolved in the main tank oil that certain insulation problems can generate over time.
Can bushing monitoring be applied to equipment other than transformers?
Yes. The same capacitive-equipment monitoring concept can be applied to instrument transformers and surge arresters when continuous insulation condition supervision is required.
What information is needed before selecting a bushing monitoring system?
Transformer type, bushing quantity, monitoring parameters, partial discharge requirement, communication protocol and installation environment should be confirmed before selecting the system.
Trusted by Utilities and Transformer Manufacturers Worldwide
Our bushing monitoring systems are deployed across power utilities, transformer OEMs, and industrial plants throughout North America, Europe, and Asia-Pacific.
Continuous dielectric loss trending flagged a bushing well ahead of its scheduled offline test — a clear save for our maintenance budget.
Utility Engineering TeamFrance
Running the integrated IN-205B3 configuration gave us insulation and PD data from the same bushing set without doubling up on hardware.
Transformer OEMSouth Korea
DL/T860 integration meant our substation automation platform picked up bushing alarms directly, with no extra gateway needed.
Grid OperatorUnited States
Not Sure Which Bushing Monitoring Configuration Fits Your Equipment?
Tell us your bushing type, quantity, and whether PD monitoring is required — our engineering team will recommend the right IN-205B configuration and, if useful, the complementary transformer monitoring solutions to pair it with.
