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Laying conditions

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–усский



Laying conditions

The cables are intended for operation in stationary mode at the ambient temperatures from

Ц from plus 50 ∞—to minus 50 ∞—Ц for cables with outer sheath of polyvinylchloride (PVC) compound

Ц from plus 60 ∞—to minus 50 ∞—Ц for cables with outer sheath of polyethylene (PE)

Ц from plus 50 ∞C to minus 35 ∞C Ц for cables with outer jacket made of polymer composition, fire-unfriendly.

The cables are laid at cable routs without limitations of level difference.

Recommended fields of application are indicated below.

Type of cable

Recommended area of application

јѕвЁгѕ, ѕвЁгѕ

For installation in ordinary soils (trenches), as well as in highly corrosive soils, on conditions that the cable is protected against mechanical damages.

јѕвЁгаѕ, ѕвЁгаѕ

For installation in damp soils, partially looded premises, in non-navigable pondsif the mechanical protection of cablesis provided.

јѕвЁ¬, ѕвЁ¬,
јѕвЁоѕ, ѕвЁоѕ,
јѕвЁоаѕ, ѕвЁоаѕ

For stand-alone installation in premises, canals, tunnels, at cable overpasses, on the troughs and for installation in dry soils on conditions that mechanical protection of cable is provided.

јѕвЁг¬, ѕвЁг¬,
јѕвЁга¬, ѕвЁга¬,
јѕвЁоаѕ, ѕвЁоаѕ

For stand-alone installation in damp premises, canals, tunnels.

јѕвЁЅѕ, ѕвЁЅѕ,
јѕвЁјкѕ, ѕвЁјкѕ

For installation underground (in trenches), where mechanical impact on cable is possible.

јѕвЁ ѕ, ѕвЁ ѕ

The same, including impact of signilcant stretching elorts on cable

јѕвЁЅ¬, ѕвЁЅ¬,
јѕвЁјк¬, ѕвЁјк¬

For stand-alone installation in premises, canals and tunnels, in dry soils, in places where mechanical impact on cable is possible.

јѕвЁ ¬, ѕвЁ ¬

The same, including impact of signilcant stretching elorts on cable.


It is allowed to install outdoors cables which have outer jacket from polymer or polymer composition, fire-unfrientaking into account decrease of the carrying capacity of cable when working projects are created, because the tempof the cable surface increases and the possibility to decrease it is not available.

When the cable with outer jacket of polymer is installed outdoors, including installation in cable constructions, it is necessary to provide additional measures of fire-fighting protection.

Cables with Ђ¬нгї, Ђѕнгї, Ђ¬нгдї markings are intended for common installation in cable constructions, premises (including fire-unsafe premises); cable with Ђ¬нгдї marЦ for use at sites where there are requirements to low emission of smoke and gas from burning or smouldering: nuclear power plants, common power plants, underground stations, high buildings, large industrial sites, etc.

Cables with ЂѕнгHFї are intended for use at sites where there are requirements to low emission of smoke corrosive gases, absence of halogens.

Cables with reinforced polyethylene are intended for use at the complicated sections of the cable lines. The complicated sections of the lines are such, where:

a) there are more than four tuns at the angles more than 30∞

b) straight sections with more than four transitions in tubes longer than 20 metres or more than two transitions in tubes longer than 40 metres.


The permissible temperatures for the conductors heating are quoted in table:

Continuous permissible temperature at operation

90 ∞—

Maximum permissible temperature at short-circuit currents, max 5 second

250 ∞—

Permissible temperature at alarm mode

130 ∞—


The duration of cable operation in alarm mode shall not exceed 8 hours per day and 1000 hours per service life.

The cables can be employed in AC voltage systems, prothe voltage values do not exceed 2.4 U0.

Cables can be installed without pre-heating if the temperaof the surrounding air is not lower than minus 15 ∞C Ц for cables with PVC insulation or polymer composition, fire-unfriendly, and minus 20 ∞C Ц for cables with polyethyljacket. If the air temperature is lower, the installation of cables is allowed only with pre-heating of the cable by eleccurrent (the duration of heating is 1-4 hours depending on conditions and cable weight) or in the heated premises (duration 20-70 hours).

Installation of cables at temperature lower than minus 30 ∞C is not recommended.

Minimum bending radius, mm, shall be 15D,
where: D Ц cable outer diameter, mm.

Cable stretching at laying shall be done by stretching device equipped with a tensile stretching control.

The stretching efforts shall not exceed:

- 30 Ќ/mm2 of cross-sectional area: for cable with multicore aluminium conductor

- 25 Ќ/mm2 of cross-sectional area: for cable with single-core aluminium conductor

- 50 Ќ/mm2 section area: for cables with copper conductor.


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