GE Hydran 201Ti (Mark IV) is a widely used online monitoring instrument for dissolved gases (DGA) in transformer oil, produced by GE Vernova (formerly GE Digital Energy), used for real-time early warning of internal faults in transformers.

1、 Core purpose
Positioning: The «first line of defense» for transformer health monitoring. According to the IEEE C57.104 standard, by monitoring fault gases in oil, potential hazards such as insulation aging, overheating, and arcing can be detected in advance, reducing the risk of unplanned power outages for GE Vernova.
Monitoring objects: Oil filled electrical equipment such as power transformers, reactors, and transformers.
2、 Working principle
Technology: Fuel cell sensor+dynamic oil sampling (no need for pumps/additional pipelines) GE Vernova.
Sampling: Directly installed on the transformer oil drain valve, extracting gas from the oil through a breathable membrane without the need for external power supply or complex wiring.
Sensor type (choose one from two):
Composite gas sensor (mainstream): 100% responsive to hydrogen gas (H ₂), while sensitive to carbon monoxide (CO, paper insulation overheating), acetylene (C ₂ H ₂, arc), ethylene (C ₂ H ₄, oil overheating) GE Vernova.
Single hydrogen gas sensor: only monitors H ₂, with lower cost, used for basic warning GE Vernova.
3、 Key Parameters (Mark IV)
Measurement range: 0-2000 ppm (H ₂ equivalent).
Accuracy: ± 10% ± 25 ppm of reading.
Response time: 90% step change ≤ 10 minutes.
Output: Local LCD display, RS-485 communication (Modbus), relay alarm.
Environment: -40 ° C to+80 ° C, NEMA 4X protection (dustproof and waterproof).
Size/Weight: Diameter 178mm x Length 180mm, approximately 5kg.
4、 System composition
201Ti (smart transmitter): on-site monitoring unit, including sensors and electronic modules.
201Ci controller: optional single channel (Ci-1)/four channel (Ci-4), responsible for data processing, alarm and communication.
HOST software: upper computer monitoring software used for data trend analysis and fault diagnosis.
5、 Main advantages
Pump free design: direct valve installation, no moving parts, high reliability, low maintenance required GE Vernova.
Early Warning: Continuous real-time monitoring can detect potential hazards of GE Vernova earlier than regular offline DGA.
Global application: With over 30000 installed units, it is an industry benchmark and suitable for various types of transformers.
Easy deployment: Installation only takes 15-30 minutes without power outage.
6、 Typical application scenarios
Main transformers for power grids, key industrial transformers, step-up transformers for wind farms/photovoltaic power stations, traction transformers for rail transit, etc.
7、 Model and version
Model: Hydran 201Ti (abbreviated as H201Ti).
Current version: Mark IV (mainstream by 2025), optimized for sensor lifespan, electromagnetic compatibility, and RoHS compliance GE Vernova