Works on Replacement of Obsolete and Worn-out Circuit-Breakers Began in MOESK’s Northern Branch

Practical stage of type design realization on the replacement of obsolete and worn-out 6-10 kV circuit-breakers began in branch of JSC “MOESK” – “Northern Electric Grids”. Works on replacement of 100 circuit-breakers are held out by own resources.

At first Bulgarian oil-poor circuit-breakers MMO-110, which were delivered way back in soviet times according to Council of Mutual Economic Assistance, will be replaced. They are not far produced, and it is a big problem to obtain spare parts for them.

SF6 tank type circuit-breakers are installed instead of oil-poor. They are characterized by high safety level, smaller area for installation, because current transformers are already built-in in tank type circuit-breaker, and low operation and technical maintenance cost.

For example, circuit-breakers EKLW24-145, equipped by arc suppressor of the improved design, have a high reliability level and proved themselves well during operation at electric grid enterprises of Russia and CIS countries. Their performance excesses many analogues.

Certification of circuit-breakers was carried out by Scientific and Technical Centre “Energetiki” of JSC “UES FGC”, technical specifications for the equipment production are agreed with JSC “IDGC” (JSC “Russian grids”). As an additional proving or circuit-breakers’ reliability specialists of Northern Electric Grids examined data of SF6-insulated switchgears’ failures statistics, which are manufactured by XD-Electric. The choice was encouraged also by a five-year warranty for the equipment, provided by the manufacturer.

Program “cost” on the replacement of obsolete and worn-out circuit-breakers is RUR bln 5. The assets are allocated from the budget of JSC “MOESK”.