Local distribution boards

Local distribution boards (LDB) are intended for introduction and distribution of 0.4 kV electric power at the power substations, power plants and industrial enterprises, for power supply, protection and backup of auxiliary power consumers of alternative current at substations, HPPs, TPPs, NPPs and other facilities of energy engineering and industry. LDB are used to arrange the auxiliary power supply of the substations and power plants with alternative current of 380 V and a frequency of 50 Hz
          LDB distinguishing features
  • The product maximum factory readiness.
  • Ability to install various types and composition of equipment in accordance with the Customer’s requirements.
  • Convenience of assembling and operation.
  • Possibility of connection both from top and bottom sides.
Auxiliaries boards (AUB) provide:
  • receiving the alternative current power;
  • distribution of the electrical power between consumers;
  • protection by the automatic circuit breakers of consumers and outgoing lines against short circuit and overload currents;
  • automatic activation of COCB in case of voltage drop on one of the inputs.
LDB operation conditions
  • LDB climatic version and placement category — Y3 in accordance with GOST 1515-69;
  • Ambient air temperature from +5° C to +40° C;
  • environment is non-explosive, free of dust, including conductive dust, corrosive vapors and gases in concentrations that destroy metal and insulation;
  • Operating conditions group in terms of exposure to environment according to GOST 17516.1-90 – M2;
  • Air relative humidity up to 80% at the temperature of 20ºС in accordance with GOST 15543.1-89
  • Installation altitude above sea level is no more than 2000m (when operating the panels at an altitude of more than 1000m.,
  • the characteristics of the devices used in the panels shall be reduced in accordance with GOST 15150-69);
  • the working position in space is vertical, deviations from the vertical position up to 5° in any direction are allowed;
  • Protection level of the AUB IP31 according to GOST 14254-96;
  • Seismic resistance is 6 points (9 points version is manufactured upon the request) per MSK- 64.
  • breaker drives power supply cabinets;
  • outdoor installation cabinets heating;
  • cooling cabinets of automated transformers (transformers);
  • charging devices;
  • emergency lighting blocks;
  • fire extinguishing pumps;
  • Electromagnetic interlocking curcuits power cabinets
  • of the circuit breakers;
  • substation control building ventilation and heating;
  • external lighting;
  • communication, CAPCS.
  • version: draw-out;
  • type: Schneider Electric, Moeller, ABB, Siemens and others.
  • Presence of the COCB;
  • control type: local, remote, long distance control;
  • version: plugged-in and stationary;
  • type: Schneider Electric, Moeller, ABB, Siemens;
  • control type: local, remote is possible;

Electronic counters of various manufacturers, which are installed on introduction leads;
Equipment of secondary switching circuits and instrumentation of foreign and Russian manufacturers: Schneider Electric, Relpol, Proton-Impulse, Electropribor, Novatek-Electro and others.
The configuration and composition of the equipment used in LVSG can be changed at the Customer’s request in accordance with the technical specification requirements.

The LDB panel consists of:
  • incoming line sections;
  • partitioning cabinets;
  • outcoming lines cabinets;
  • control and automation cabinets.
The LDBs provide:
  • receiving the alternative current power;
  • distribution of the electrical power between consumers;
  • protection by the automatic circuit breakers of consumers and outgoing lines against short circuit and overload currents;
  • automatic activation of COCB in case of voltage drop on one of the inputs.
Design features

The LDB panel structure is made in the form of assembled galvanized steel cabinets or welded sructure cabinets. Upon request, the AUB are performed in a seismic resistant version of up to 9 points according to MSK-64 scale.
The LDBs are manufactured in the form of cell-type shields with draw-out, plugged-in or stationary automated circuit breakers as domestic, so imported production.
The LDB can be connected to one or two transformers (other options are possible) with a capacity from 63 kVA to 2500 kVA. The panel placement is possible in one or two rows. In the case of double-row version, the panels can additionally be equipped with a bus bar bridge. All the versions are implemented according to the methods of bus bars or cables supplying.
Cabinet metal structure types: cabinets of Rittal, Prisma P. production
Cabinets maintenance: single or double rows.
Secondary switching circuits are laid in cable boxes.
Passage and measuring clamps, manufactured by the company Weidmüller, Klemsan, Phoenix Contact.

The monitoring and control system includes input/output modules of analog and discrete signals and a controller, integrated by the RS.485 serial interface, installed in the compartments of the switchboard cabinets of the LDB.

Technical parameters and characteristics

Parameter nameParameter value
Rated voltage, kV0.4
Current typealternative
Frequency of alternative electric current, Gz50
Rated current of bus bars , Aдо 2500
Outgoing line rated current , A100…2500
Entrance bay rated current , A100…2500
Conventional thermal current, kA50, 70
Maintenance typeone-sided, two-sided
Connection methodCable, bus bar
Overall dimensions, mm 
— width400, …, 1200
— depth600
— height2200