NBS (National Bank of Serbia)

Transformer substation reconstruction


A consortium between Log Design and Elgra Vision was awarded the contract for NBS (National Bank of Serbia) transformer substation reconstruction based on the „design and build“ conditions. Log Design was responsible for designing and equipment purchasing, while Elgra Vision was responsible for all on-site electrical works.

Our scope of supply was planning and executing the replacement of the existing MV switchgear and LV switchboards. The new design had to conform with the existing space and openings in the slab, as well as with existing exhaust ducts.

Work was only allowed during the weekend since the NBS data center supports all the banking and financial transactions within Serbia. In the first two weekends, it was only permitted to work from Saturday morning to Sunday afternoon. Sunday evening, the NBS data center and entire office building must be in operation. After the first two weekends, our government published a state of emergency because of the COVID19 pandemic which limited working hours to Saturday from 7 a.m. up to 7 p.m.

National Bank of Serbia transformer substation reconstruction project summary:

  • SS 10/0.4 kV, 6x1000kVA (transformers) + 2x630kVA (DG sets)
  • MV switchgear ABB UniSec - 11 panels
  • 5 PCCs (Logstrup/ABB) overall
  • 3 PCCs with busbar rating 2000 amps
  • 2 PCCs with busbar rating 1000 amps
  • 35 panels overall
  • 14 withdrawable ACBs
  • 108 withdrawable units
  • 1.5 MVAr modular detuned PFC
  • SCADA remote control and power monitoring