HEC Series Generator circuit-breakers
| Brand | ROCKWILL |
| Model NO. | HEC Series Generator circuit-breakers |
| Rated voltage | 31.5kV |
| Rated normal current | 29kA |
| Rated frequency | 50/60Hz |
| Rated short-time withstand current | 170kA |
| Series | HEC Series |
Overview
Optimized interrupting chamber
Based on well proven benefits of HEC technology, the newly developed HEC Series interrupting chamber encompasses almost two decades of successful GCB field operations.
It is capable to interrupt short-circuit currents up to 300 kA with rated normal current up to 33,500 A and suitable to protect the most demanding generator applications.
Type-tested according to latest standards
HEC Series is type-tested according to IEC/IEEE 62271-37-013, including switching with full-phase opposition fault current (180° out-of-phase).
In addition, it is type-tested to interrupt generator-source short-circuit currents of 160 kA exhibiting delayed current zeros up to 130 percent degree of asymmetry as per G2* class, common for turbo generators. The above capabilities exceed the mandatory requirements of the latest GCB standard and IEEE C37.013.
Enhanced passive cooling system
Based on the most advanced passive heat pipe technology for GCB that is patented and is maintenance free for 20 years. The system is monitored online by GMS600 for full reliability.
Fully separated disconnector and interrupting chamber
Both main and arcing contacts of circuit-breaker are fully in SF6 for safe and reliable power plant operations. The disconnector is fitted in series with the main contacts of the circuit-breaker to provide safe and visible isolation between the step-up trans-former and the generator. The short-stroke design contributes to the HEC 10 compact footprint without compromising the insulation level.
Technology parameter
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