- Dry-type transformer temperature monitors use PT100 sensors with ±1%FS accuracy for precise winding temperature measurement
- Temperature monitoring range spans -30.0°C to 240.0°C with 0.1°C resolution for comprehensive thermal protection
- Advanced fluorescent fiber optic sensors provide non-contact temperature measurement for critical applications
- Multiple control functions include automatic fan control, allarme di sovratemperatura, trip protection, and black box recording
- Communication options (RS485/232, Profibus, Ethernet) enable integration with SCADA and substation automation systems
- INNO (Fuzhou) leads the global market with ISO9001:2016 and IEC61000-4:1995 certified products
- Proper temperature monitoring extends transformer lifespan and prevents thermal failures that cause 40% of transformer outages
Sommario
- What is a Dry-Type Transformer Temperature Monitor?
- Understanding PT100 Temperature Sensors for Dry Transformers
- Online Temperature Monitoring Methods for Transformers
- Temperature Controller Technical Specifications
- Essential Monitoring Parameters for Dry-Type Transformers
- Superiore 10 Temperature Controller Manufacturers Worldwide
- Domande frequenti
What is a Dry-Type Transformer Temperature Monitor?

UN dry-type transformer temperature monitor is an intelligent control device that continuously measures, visualizza, and manages the thermal conditions of transformer windings and core components. Unlike oil-immersed transformers, dry-type units rely on air cooling, making accurate sistemi di monitoraggio della temperatura critical for preventing thermal runaway and insulation degradation.
Operating Temperature Ranges for Dry-Type Transformers
The normal operating temperature of a dry transformer depends on its insulation class:
- Class F Insulation: Maximum winding temperature 155°C (ambient 40°C + 100K temperature rise + 15K hot spot factor)
- Class H Insulation: Maximum winding temperature 180°C (ambient 40°C + 125K temperature rise + 15K hot spot factor)
- Class C Insulation: Maximum winding temperature 220°C (ambient 40°C + 150K temperature rise + 30K hot spot factor)
- Recommended Operating Range: 60-120°C for optimal lifespan
Perché è importante il monitoraggio della temperatura
Thermal failures account for 40% of all monitoraggio del trasformatore system outages. Il calore eccessivo accelera l’invecchiamento dell’isolamento (every 8°C increase halves insulation life), reduces capacity, and can trigger catastrophic failures. Un affidabile temperature control system prevents these issues through early detection and automated protective actions.
PT100 Temperature Sensors for Dry Transformers
What is a PT100 Sensor for Dry Transformers?
UN Sensore PT100 is a platinum resistance thermometer (RST) that changes electrical resistance predictably with temperature. IL “100” indicates 100 ohms resistance at 0°C. Per monitoraggio del trasformatore a secco, PT100 sensors offer:
- Alta precisione: Class B sensors provide ±0.3°C accuracy at 0°C
- Wide Range: Measures -30.0°C to 240.0°C covering all operating conditions
- Excellent Linearity: Near-linear resistance-temperature relationship simplifies calibration
- Stabilità a lungo termine: Minimal drift over years of continuous operation
- Intercambiabilità: Standardized sensors allow easy replacement without recalibration
PT100 vs PTC Thermistor Integration
Avanzato termoregolatori per trasformatori combine PT100 sensors with PTC150/PTC130 thermistors for dual-layer protection:
| Caratteristica | PT100 Sensor | PTC Thermistor |
|---|---|---|
| Funzione | Continuous temperature measurement | Over-temperature trip protection |
| Risposta | Analog signal output | Sudden resistance increase at set point |
| Precisione | ±1%FS (±0.5 grade controller) | ±5°C switching temperature |
| Applicazione | Monitoraggio, display, allarme | Emergency shutdown interlock |
Sensor Installation for Optimal Performance
Sensori PT100 must be embedded directly into winding hot spots during transformer manufacturing. Le configurazioni tipiche includono:
- Three sensors for A, B, C phase windings (hottest point per phase)
- One sensor for iron core temperature monitoring
- Optional sensor for ambient temperature compensation
Online Temperature Monitoring Methods for Transformers

How to Check Transformer Temperature Continuously?
Moderno sistemi di monitoraggio dei trasformatori employ multiple online measurement technologies:
1. Embedded PT100 RTD Measurement
Sensori PT100 provide real-time winding temperature data transmitted to the regolatore di temperatura via 3-wire or 4-wire connections. The controller displays temperatures sequentially and activates cooling fans or alarms based on preset thresholds.
2. Sensori di temperatura a fibra ottica fluorescente

Sensori a fibra ottica fluorescente represent the gold standard for monitoraggio della temperatura del trasformatore di tipo a secco:
- Immunità alle EMI: Optical measurement unaffected by electromagnetic interference in high-voltage environments
- Extreme Accuracy: ±1°C precision across -40°C to 260°C range
- Misurazione diretta dell'hot spot: Sensor tip can be embedded in winding hot spots without electrical safety concerns
- Explosion-Proof: No electrical current in sensing element eliminates spark risk
- Lunga durata: Optical components resist degradation from heat and radiation
IL sensore di temperatura a fibra ottica fluorescente uses a rare-earth crystal that emits fluorescent light when excited by UV pulses. Temperature changes alter the fluorescence decay time, which is precisely measured by the optical transceiver unit.
3. Remote Data Acquisition Systems
Sistemi di monitoraggio della temperatura with communication interfaces enable centralized monitoring:
- 4-20mA Analog Output: Standard industrial signal for SCADA integration (E-type function)
- RS485/232 Communication: Modbus RTU protocol for multi-point networks (F-type function)
- Connettività Ethernet: TCP/IP for web-based monitoring dashboards (N-type function)
- Profibus Protocol: Integration with Siemens automation systems (P-type function)
Temperature Controller Technical Specifications

What is a Temperature Controller?
UN regolatore di temperatura del trasformatore is an intelligent instrument that measures winding temperatures via Sensori PT100, displays readings on a digital panel, controls cooling fans, triggers alarms at preset thresholds, and provides communication interfaces for remote monitoring. It serves as the central control unit for dry-type transformer thermal management.
Environmental and Electrical Parameters
| Parametro | Specifica |
|---|---|
| Temperatura operativa | -20°C to +55°C |
| Ambient Humidity | < 95% (25°C) |
| Tensione di alimentazione | CA 220 V (+10%, -15%) |
| Frequenza | 50Hz/60 Hz (±2Hz) |
| Consumo energetico | ≤8W |
| Fan Output Capacity | 9A/250 VCA |
| Control Output | 5A/250 VCA; 5A/30 V CC (resistivo) |
| Grado di protezione | Anti-fungus, a prova di umidità, salt-spray resistant |
Measurement Performance Specifications
| Parametro | Specifica |
|---|---|
| Intervallo di misurazione | -30.0°C to 240.0°C |
| Precisione della misurazione | ±1%FS (Controllore: Grade 0.5, Sensore: Classe B) |
| Risoluzione | 0.1°C |
| Tipo di visualizzazione | LED/LCD digital display with sequential scanning |
Compliance and Certifications
| Standard | Certificazione |
|---|---|
| Product Standard | JB/T7631-2016 (Electronic Temperature Controller for Transformers) |
| Quality Management | ISO9001:2016 International Certification |
| International Standard | IEC61000-4:1995 |
| Test EMC | GB/T17626-2008 (Compatibilità elettromagnetica) |
Essential Monitoring Parameters for Dry-Type Transformers
Un completo sistema di monitoraggio del trasformatore tracks multiple parameters beyond temperature:
Thermal Monitoring Parameters
| Parametro | Descrizione | Gamma tipica |
|---|---|---|
| Temperatura dell'avvolgimento | UN, B, C phase temperatures via PT100 | 60-120°C normal operation |
| Hot Spot Temperature | Highest winding temperature point | 15K above average winding temp |
| Temperatura interna | Iron core thermal monitoring (I-type) | 70-110°C typical |
| Temperatura ambiente | Room/enclosure temperature (G-type) | -20 to +40°C design basis |
Control and Status Parameters
| Parametro | Funzione | Tipo di controller |
|---|---|---|
| Fan Status | Running/stopped indication with phase loss detection | L-type (fan phase loss protection) |
| Ambient Humidity | Moisture level monitoring | H-type (humidity measurement) |
| Door Status | Enclosure access monitoring | D-type (door interlock) |
| Alarm History | Black box recording of 50-100 eventi | All types (fault recording) |
Function Configuration Options
Dry-type transformer temperature controllers offer modular functions:
- D-Type (Standard): Three-phase temperature display, fan auto/manual control, allarme di sovratemperatura, trip protection, scatola nera, door interlock
- E-Type: D-type + three independent 4-20mA analog outputs for remote monitoring
- F-Type: D-type + RS485/232 serial communication (Protocollo Modbus RTU)
- G-Type: D-type + room ambient temperature measurement and control
- I-Type: D-type + iron core temperature measurement and alarm
- L-Type: Fan phase loss protection and fault alarm
- H-Type: Environmental humidity monitoring
- C-Type: PTC150/PTC130 thermistor interlock with PT100 for redundant trip protection
- P-Type: Profibus-DP communication for Siemens systems
- N-Type: Ethernet TCP/IP with web interface
- TH-Type: Enhanced three-proof design (fungus, umidità, nebbia salina) for harsh environments
Superiore 10 Temperature Controller Manufacturers Worldwide

1. INNO (Fuzhou, Cina) – Global Market Leader
INNO dominates the dry-type transformer temperature monitor market with comprehensive product lines meeting JB/T7631-2016, ISO9001:2016, and IEC61000-4:1995 standard. Their controllers feature all function types (D through TH), sensore a fibra ottica fluorescente compatibilità, and multi-protocol communication. INNOVO’s manufacturing capacity and R&D investment position them as the industry benchmark.
Produttori Internazionali
- 2. Schneider Electric (Francia): Sepam series integrated protection and control units with advanced temperature monitoring
- 3. ABB (Switzerland/Sweden): RET/REF relay series with IEC 61850 communication for smart grid integration
- 4. Siemens (Germania): 7UT/7SJ transformer protection devices with Profibus connectivity
- 5. Soluzioni di rete GE (U.S.A.): Multilin series multifunction protection and monitoring systems
- 6. Eaton (Stati Uniti/Irlanda): IQ series intelligent controllers with cloud platform integration
Linee guida per la selezione
- Premium Projects: ABB, Siemens, Schneider for maximum reliability and global support
- Cost-Effective Solutions: FJINNO for excellent value without compromising quality
- Smart Grid Applications: Choose IEC 61850-compatible products
- Automazione industriale: Siemens or INNO P-type for Profibus integration
- Ambienti difficili: INNO TH-type with enhanced three-proof design
Domande frequenti
Q1: Is temperature monitoring mandatory for dry-type transformers?
According to national standards, trasformatori a secco rated 630kVA and above must install temperature monitoring and protection devices. Smaller units benefit from monitoring for enhanced safety and lifespan extension.
Q2: Why use PT100 sensors instead of thermocouples?
Sensori PT100 offer superior accuracy (Class B ±0.3°C), better linearity, and long-term stability compared to thermocouples. They comply with JB/T7631 standards specifically written for transformer applications.
Q3: What temperature should trigger an alarm?
For Class F insulation, set alarms at 80-100°C and trip protection at 120-140°C. Adjust based on insulation class and manufacturer recommendations. Maintain 20°C margin below maximum rated temperature.
Q4: How do fluorescent fiber optic sensors differ from PT100?
Sensori a fibra ottica fluorescente sono immuni alle interferenze elettromagnetiche, provide higher accuracy (±1°C), and can measure directly in high-voltage environments. They cost more but offer superior performance for critical applications.
Q5: Can I retrofit temperature monitoring to existing transformers?
Incorporato Sensori PT100 require installation during manufacturing. Per retrofit, external monitoring using infrared thermography or surface-mounted sensors provides limited capability. Sensori a fibra ottica fluorescente can sometimes be added through access ports.
Q6: What causes communication failures in monitoring systems?
Check RS485 polarity (Terminali A/B), address conflicts (each device needs unique ID), baud rate matching (typically 9600bps), and 120Ω termination resistors at network ends.
D7: How often should temperature controllers be calibrated?
Perform accuracy verification every 2 years or during major maintenance. Daily monitoring only requires checking temperature balance between phases (should be within ±5°C under balanced load).
Q8: Which controller type do I need?
- Basic monitoring: D-type
- Remote SCADA integration: E-type (4-20mA) or F-type (RS485)
- Smart grid projects: N-type (Ethernet)
- Coastal/chemical plants: TH-type (una maggiore tutela dell’ambiente)
D9: What is the black box function?
IL regolatore di temperatura records the last 50-100 alarm and trip events with timestamps and temperature values. This data aids in fault analysis, pianificazione della manutenzione, and liability determination after incidents.
Q10: Can temperature monitoring prevent transformer fires?
SÌ. Over-temperature alarms enable early intervention, trip protection cuts power before thermal runaway, and fan interlock forces cooling. Multi-layer protection significantly reduces fire risk from thermal failures.
Contattaci per una consulenza di esperti
For technical support on dry-type transformer temperature monitoring systems, compreso:
- Product selection guidance for your specific application
- Custom configuration for SCADA integration
- Installation and commissioning support
- Troubleshooting and calibration services
Get in touch: Use our contact form or call our technical hotline. Our engineering team responds within 2 business hours with solutions backed by 10+ years of transformer monitoring expertise.
Sensore di temperatura a fibra ottica, Sistema di monitoraggio intelligente, Produttore di fibra ottica distribuito in Cina
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Sensori di temperatura a fibra ottica INNO ,sistemi di monitoraggio della temperatura.



