20.August
Overview of TJO Series Transformers: Reliability, Resilience, and Efficiency in Harsh Environments
The TJO series transformers, manufactured using hydrophobic cycloaliphatic epoxy (HCEP), offer high resistance to external factors and are highly reliable in outdoor environments. HCEP not only provides excellent protection against arcing, ozone, and UV radiation but also possesses high mechanical strength, ensuring the equipment’s durability and safety even under challenging operating conditions.
Main Advantages of TJO Transformers
Measurement Accuracy: TJO transformers are specifically designed for phase voltage measurement, offering high load capacity while maintaining the required accuracy class.
Resistance to Environmental Factors: The hydrophobic HCEP material performs exceptionally well in wet environments, minimizing the risk of arcing and protecting the equipment from contamination.
Optimal Solution for Measurements: The application of ResiVolt technology effectively counters fast transient overvoltages (VFTO) that can occur during the operation of inverters or switchgear.
Purpose and Application
The TJO 7 series voltage transformers are ideal for use in electrical networks up to 35 kV. They are used in both measurement and protection circuits, ensuring reliable performance in various conditions, including aggressive environments and coastal areas.
Technical Features and Design
The TJO series transformers feature a single primary winding, with one side earthed during operation and the other isolated from the ground. Most models come equipped with two secondary windings: one for measurement or protection circuits and the other for open-delta connections in three-phase systems.
All secondary winding terminals are housed within a molded, hermetically sealed enclosure that protects against external factors. The design facilitates easy installation with integrated hanging loops and bolted connections for simpler transportation and setup. Additionally, the transformers offer flexible application options with two primary winding voltage settings and a switch on the secondary side.
Main parameters
| Description of parameters | Unit | Parameters |
| Rated primary voltage | kV | 20:√3; 22:√3; 27:√3; 30:√3; 33:√3; 35:√3 |
| Rated secondary voltage | V | 100:√3; 110:√3 |
| Rated voltage of an open triangle circuit | V | 100:03; 110:03 |
| Rated frequency | Hz | 50 |
| The greatest work stress | kV | 40,5 |
| Test voltage of industrial frequency, 1 min. | kV | 95 |
| Lightning impulse test voltage (peak) | kV | 200 |
| Maximum load/accuracy class — measuring winding | VA/cl | 50/0.2; 100/0.5; 150/1 |
| Maximum load/accuracy class — additional winding | VA/cl | 200/3P or 6P |
Reliability and Compliance with Standards
The TJO series transformers are engineered to meet international standards (IEC, EN, VDE, ANSI, BS, DSTU), ensuring high reliability. The HCEP encapsulation provides superior performance even in contaminated and humid environments, while the increased creepage distance significantly reduces the risk of electrical breakdown.
Versatility in Installation
TJO transformers can be mounted in vertical, cantilevered, or inverted positions. For enhanced reliability, it is recommended to use strain relief devices when connecting cables. The aluminum base plate is compatible with the dimensions of other popular models on the market, simplifying the integration of these transformers into existing systems.
The TJO series transformers are the ideal solution for ensuring stable operation of power supply systems under difficult conditions. Their versatility, resistance to environmental factors, and proven reliability make them an excellent choice for technicians seeking long-lasting, dependable equipment.