Velatia Ormazabal ormaSET-M, Общее руководство по инструкции

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Installation General Instructions
ormaSET-M
IG-199-EN version 03
5.6.1 Earth Circuit
A main earthing conductor system is provided to connect to
the earth all components of the prefabricated substation:
► The enclosure of the prefabricated substation.
► The enclosure of the medium-voltage switchgear
and control gear.
► The metal shields and the earthing conductors of
the medium-voltage cables
► The transformer tank.
► The frame and/or enclosure of the low-voltage
switchgear.
► The earthing connection of automatic controls and
remote-control devices.
Optionally this earth circuit can be connected to the
protective earth disconnection box fitted to the inner side of
ormaSET-M Transformer Substation, to the left of the
access door for the low voltage board, using a bare copper
cable with a cross-section of 50 mm
2
.
The metallic parts of ormaSET-M prefabricated substation
enclosure is designed to carry 30 A (d.c.) from themselves
to the prefabricated substation main earthing point, with a
voltage drop of maximum 3 V. Installer or final user shall
provide adequate earthing measures around the
prefabricated substation in order to prevent dangerous
touch and step voltages.
The torques to be observed are as follows:
Fig. 5.6: Disconnection protection box
5.6.2 Service Earth (Neutral)
Optionally, an earthing feeder (neutral) can be supplied
that connects the neutral busbar of the distribution
transformer to the disconnection box fitted on the right side
of the low voltage compartment.
This connection is made using an insulated copper cable of
0.6/1 kV with a cross-section of 50 mm
2
.
Fig. 5.7: Neutral disconnection box
METRIC
TORQUE [Nm]
Steel
8.8
Stainless steel A2
M8 21
M10 38
M12 60