16
DCGear
P R O D U C T M A N U A L
4 Technical characteristics
—
4.1 General information
4.1.1 Switchgear description
The proposed DCGear are equipment with metal
enclosure metal-clad type, for indoor, a internal
arc proof and comply with norms GB/T 25890,
EN 50123, IEC 61992, IEEE C37.20.1, EC/TR 61641,
DIN 60439-1.
Each panel is composed of a series of modular
cells, coupled between them, in which are mounted
the switchgear and control devices, measurement
and protection, with the relative connections to
the power circuits and auxiliary.
The switchgear shall be made by metal enclosed
cubicles with IP20 total protection degree and
suitable for indoor installation.
The feeders cubicles with open doors is guaranteed
the protection IP20.
The switchgear will be made with a free standing
structure and its external casing will be made
of bolted panels and doors on the front side.
4.1.1.1 Metal-clad cells
A cell-type metal-clad is divided into compartments
properly segregated from each other by metal
diaphragms intended to be brought to the ground.
The cubicle is composed of three separate
compartments:
•
HSCB compartment
•
Low voltage compartment
•
Rear bus-bar compartment
In order to make easier the maintenance operations,
the rear panels will be hinged.
Panels and/or diaphragms will divide the cubicle
indoor side in cells, which will contain the single
circuits. The main frame will be made of plates
with 2 mm of minimum thickness. The doors will
be made with plates 2 mm of minimum thickness
and will be provided with locks and/or bolts. Also
panels and partitions will be realized with plates
2 mm of minimum thickness and fixed by bolts.
All the metallic parts will be connected to the earth
collector. The metallic parts of the withdrawable
equipment remain connected to the earth also in
the test, disconnected and between each position.
An earthing bar will be provided along the whole
switchboard internal sides. An adequate connection
will be fitted on this bar for the connection to
the earth of the substation.
Lifting fittings or anchor bolts will be provided
on the upper part of the cubicles.
No insulating panel is required inside the cell.
The performance of the various equipment and
insulation distances maintained in the design
phase are secured only by the metal structure
and the insulating diaphragms.
The division into segregated compartments
metal-clad panel allows you to have several
benefits over metal-enclosed equipment of for
which, if any, are identified fewer compartments
segregated.
•
Safety accessibility in different compartment
•
Inspection, maintenance and/or replacement
of the various components, in particular of the
main equipment withdrawable (switch and
rectifier) without danger to personnel of
accidental contact with live parts
•
Limited risk of failure compromise the operation
of the other components in adjacent
compartments in the same cell
4.1.1.2 Internal arc proof cell
The DCGear panel guaranteed an internal arc
protection for value up to 50 kA for 250 ms .
As indicate in document IEC 61641, a panel with
internal arc proof allows to have the following
benefits:
•
Limit the risk of injury to personnel near the
equipment in case of internal arc
•
Limit the damage of the panel to one section
affected by the fault
4.2 Main electrical characteristics
The main electrical characteristics of the DC section
are the follows:
•
Service voltage 750 V/1500V
•
Rated voltage 900 V/1800 V
•
Insulation voltage
1800 V/3000 V
•
Level of insulation
according GB/IEC/EN
-
Over-voltage degreed OV4
-
Pollution degrees
PD4
-
Withstand voltage at 50 Hz for 1 min. to
earth and between the poles 9.2 kV
-
Withstand voltage at 50 Hz for 1 min. across
clearance-inside
11 kV
-
Lightning rated voltage to earth and
between the poles
20 kV
-
Lightning rated voltage across
clearance-inside
24 kV
•
Bus bar currents
up to 6 kA
•
Power supply voltages of the auxiliary circuits
24±15% Vdc
110±15% Vdc
230±15% Vdc
•
Degree of protection of Feeder (Cubic/LV
Comp.)
IP20/IP40
•
Degree of protection of VLD panel IP40
4.3 Environmental condition
The environmental conditions, refer to the
micro environment in which equipment is
installed, are:
•
Type of installation
indoor (TPS
equipment room)
•
Operating temperature -5 °C/+40 °C
•
Storage temperature -20 °C /+50 °C
•
Altitude above sea level below 1200 m
•
Relative humidity
<90%
4.4 Standard reference
The panels of the present technical description
is designed and built in compliance with the
following main norms:
•
GB/T 25890 “Railway applications” – Fixed
installations – DC switchgear
•
IEC 61992 “Railway applications” – Fixed
installations – DC switchgear
•
CEI EN50123 “Railway applications” – Fixed
installations – DC switchgear
•
EN-50526 “Railway applications” – Fixed
installations – D.C. surge arresters and
voltage limiting devices
•
EC/TR 61641
•
DIN 60439-1
