Pursuant to Article 116 of the Energy Law

3.2.3.
 
V
OLTAGE
 
3.2.3.1. Nominal values of voltage in the transmission grid of the Republic of Serbia are: 400 
kV, 220 kV and 110 kV. 
3.2.3.2. The value of voltage in normal operating conditions in any point of the grid 400 kV, 
220 kV, 110 kV is within the following range:
- 400 kV grid: between 380 kV and 242 kV; 
- 220 kV grid: between 198 kV and 242 kV; 
- 110 kV grid: between 99 kV and 121 kV. 
3.2.4.
 
F
REQUENCY
 
3.2.4.1. Nominal value of frequency is 50 Hz. When transmission system of the Republic of 
Serbia operates within the interconnection, values from the Grid Code on operation of 
interconnection are applied to allowed deviations from the nominal value of frequency in the 
transmission grid. 
3.2.4.2. In cases when the transmission system of the Republic of Serbia operates in isolation 
from the neighbouring transmission systems, the allowed frequency in the transmission grid 
in quasi-stationary state is 50 Hz 

0.5 Hz. 
3.2.5.
 
S
ECURITY CRITERION 
“N-1” 
3.2.5.1. Security criterion “N-1” can foresee outage in consumption, providing it is 
foreseeable and limited to local area. 
3.2.5.2. Security criterion “N-1” is not applied to “radially fed” consumption. 
3.2.5.3. Busbar and bus coupler bay outages are not taken into consideration when analysing 
if Security criterion “N-1” is met. 
3.2.5.4. Security criterion “N-1” is tested on models, which apart from the JSC EMS 
transmission system, include models of other transmission system, in accordance with the 
rules on operation of interconnection. 
3.2.6.
 
S
HORT