A medium voltage resin cast potential transformer, of which the function is as similar as a power distribution transformer, is designed to convert voltage. However, power transformers adjust voltage primarily to enable efficient transmission and distribution of electricity, typically with capacities rated in kVA or MVA, while potential transformers serve a measurement and protection role. the main function of a medium voltage resin cast potential transformer is to supply operating power to metering instruments and protective relays, to enable accurate monitoring of line voltage, power, and energy consumption. Potential transformers also provide critical input for protection schemes to safeguard high value assets such as transmission lines, motors, and power transformers during fault conditions. Because of those functions, potential transformers are designed with relatively small capacities, usually just a few VA to several dozen VA, and rarely exceeding 1000 VA.
| Type | Rated Voltage Ratio (kV) | Accuracy Class | Accuracy Class and Rated output cosΦ=0.8 | The Max. Output (VA) | |||
| 0.2 | 0.5 | 1 | 6(P) | ||||
| JDZX10-3A | (3/√3)/(0.1/√3)/(0.1/3) | 0.2/6P 0.5/6P 1/6P | 15 | 30 | 60 | 50 | 200 |
| JDZX10-6A | (6/√3)/(0.1/√3)/(0.1/3) | ||||||
| JDZX10-10A | (10/√3)/(0.1/√3)/(0.1/3) | ||||||
Q: What is the function of a medium voltage resin cast potential transformer in switchgear?
A: A potential transformer is used to step down the primary system voltage to a standardized lower value that can be safely supplied to measuring instruments, energy meters, and protective relays. In medium voltage switchgear, resin cast potential transformers provide galvanic isolation between the primary voltage system and secondary voltage control circuits, to ensure both accuracy and operator safety.
Q: Why is resin cast technology preferred for medium voltage potential transformers?
A: Resin cast PTs use epoxy resin as an insulating and encapsulating material. This technology provides excellent performance on electrical insulation, high mechanical strength, resistance to moisture and dust, and strong protection against partial discharge. As a result, resin cast potetial transformers are particularly suitable for indoor switchgear applications where compact design and long life scale reliability are critical.
Q: What are the typical voltage ratings for medium voltage resin cast PTs?
A: Medium voltage resin cast potential transformers are generally designed for systems from 3.6 kV up to 36 kV, which depends on the switchgear design. The secondary output voltage is usually standardized at 100 V or 110 V, which is the voltage level between phase to phase, or 100/√3 V or 110/√3 V, which is the voltage level between phase to neutral, in line with IEC standards.
Address
No. 391, Jingqi Road, Yanpan Industrial Zone, Yueqing City, Zhejiang Province, China
Tel
