Is the open-type current transformer good? What are the disadvantages of the open-type current transformer?

Open-type current transformers, also known as open-type current transformers, are suitable for indoor installations with rated voltages of 10kV and below. They are widely used in circuit control, measurement, line modification, metering, and protection. So, how good are they, and what are their drawbacks?

The open-type current transformer features a high-strength PVC casing and a fully cast busbar construction. During installation, the transformer snaps directly onto the cable, with three silicone rubber rings pressing against the cable to ensure a tight connection. The core is made of high-quality silicon steel sheets, and the secondary conductors are evenly wound around the core. The greatest advantage of this open-type structure is that it can be installed quickly and easily without cutting the cable.

The applicable scope of open-type current transformers also has clear requirements: the installation site altitude does not exceed 3000 meters; the ambient temperature is between -25℃ and +40℃; the outer diameter of the primary cable can be φ8-φ240mm; the input range is 0-60kA; the output can be selected from 0-500mA, 1A or 5A, 5VDC or 4-20mA (customer-defined), and there is no pollution, corrosive and explosive media in the atmosphere that seriously affect the insulation performance of the transformer.

However, open-type current transformers also have some disadvantages. First, the operating noise is relatively high, and noticeable noise will be generated during operation, which may interfere with the surrounding environment. Secondly, the heating phenomenon is more obvious. After long-term operation, the temperature of the transformer itself will rise, which not only affects its service life, but may also have a thermal impact on surrounding equipment. In addition, the measurement error is relatively large. Since the link of the induced current in the open-type current transformer is disconnected, the inductive core is not a sealed whole, the magnetic circuit efficiency at the gap is reduced, and it is difficult to fully fit after the opening, which will have a certain impact on the induction effect and accuracy, and thus lead to an increase in measurement error. Finally, the price is relatively high. Compared with traditional transformers, open-type current transformers are more complicated in design and manufacturing process, which increases their cost and the price is relatively high.

Overall, open-type current transformers offer significant advantages in terms of ease of installation, but they also have disadvantages such as loud operating noise, significant heat generation, large measurement errors, and high price. In practical applications, users must select a suitable type based on their specific needs to ensure both performance and cost-effectiveness.