Electrical Connection; Power Distribution System - Hyundai DHY22KSE User Manual

2.10
Electrical Connection
Only full qualified and experienced electrical
technicians should carry out electrical installation,
service and repair work.
Warning:
! Make electrical connections in compliance with
relevant electrical codes, standards or other
requirements.
2.10.1
Cabling
Due to movement of generating sets on their
vibration mounts, the electrical connection to the set
should be made with flexible cable. The cable must
be suitable for the output voltage of the generating
set and the rated current of the set. In determining
the size, allowances should be made for ambient
temperature. Method of installation, proximity of
other cables, etc. All connections should be carefully
checked for integrity.
Current carrying capacity of power cables that will be
given in APPENDIX A. On the other hand, there is a
one more important point while cable cross sections
are being selected. If the distance between load and
generator is too length, voltage falling at the load
side can be too much at the transient current
duration. The voltage drop across a cable can be
determined as follows:


   
3 L I Rcos

ΔU
1000
ΔU Voltage drop (V)
L Length of conductors (m)
I Rated current (A)
R Resistance (Ω/km to VDE 0102)
X Reactance (Ω/km to VDE 0102)
Refer to APPENDIX E Cable Current load standard.
2.10.2
Grounding / Earthing Requirements
The frame of the generating set must be connected
to an earth ground. Since the set is mounted on
vibration isolators, the ground connection must be
flexible to avoid possible breakage due to vibration.
Ground connection cables or straps should have at
least full load current carrying capacity and meet
applicable regulations.
2.10.3
Insulation Test
Before starting the generating set after installation,
test the insulation resistance of the windings. The
Automatic Voltage Regulator (AVR) should be
disconnected and the rotating diodes either shorted

Xsin )
out with temporary links or disconnected. Any
control wiring must also be disconnected.
A 500 V Megger or similar instrument should be used.
Disconnect any earthing conductor connected
between neutral and earth and megger an output
terminal to earth.
The insulation resistance should be in excess of 1MΩ
to earth. Should the insulation resistance be less than
1MΩ winding must be dried out.
2.11
Power distribution system
Our diesel engine generator set use three phase five
line system for power distribution. That is, three
phase live wires, one neutral line, one ground line.
The neutral line and the ground line are not
connected. Users can choose three phase four lines
for power distribution according to requirement that
is to connect the neutral line to the ground (base
frame), so that to solve the problem of feint that the
neutral line sometimes is electriferous.
Note:
HYUNDAI Power series diesel engine generator sets
require users to safely connect generator sets and
base frames to the ground, please refer to the ground
label for connecting point.
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