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SECTION 5 |
to the Negative terminal of the unit). If the input is connected in reverse
polarity, external DC fuse in the input side will blow and may also cause
permanent damage to the inverter.
Connection From batteries / external Charge
Controller To The DC Input Side – Sizing of
Cables And Fuses
WARnInG!
The input section of the inverter has large value capacitors
connected across the input terminals. As soon as the DC input
connection loop (battery (+) terminal
input terminal of G4
negative input terminal of the G4
battery (–) terminal) is completed, these capacitors will start
charging and the unit will momentarily draw very heavy current
that will produce sparking on the last contact in the input loop
even when the on / oFF switch on the inverter is in the oFF
position.
ensure that the fuse is inserted only after all the
connections in the loop have been completed so that
sparking is limited to the fuse area.
Flow of electric current in a conductor is opposed by the resistance of the
conductor. The resistance of the conductor is directly proportional to the
length of the conductor and inversely proportional to its cross-section
(thickness). The resistance in the conductor produces undesirable effects
of voltage drop and heating. The size (thickness / cross-section) of the
conductors is designated by AWG (American Wire Gauge). Conductors
thicker than AWG #4/0 are sized in MCM/kcmil.
Conductors are protected with insulating material rated for specific
temperature e.g. 90˚C/194˚F. As current flow produces heat that affects
insulation, there is a maximum permissible value of current (called
"Ampacity") for each size of conductor and temperature rating of its
insulation. The insulating material of the cables will also be affected by
the elevated operating temperature of the terminals to which these are
connected. Ampacity of cables is based on UL-1741 and the National
Electrical Code (NEC)-2011. Please see details given under "Notes for
Table 5.1", page 26.
The DC input circuit is required to handle very large DC currents and
hence, the size of the cables and connectors should be selected to ensure
minimum voltage drop between the battery and the inverter. Thinner
cables and loose connections will result in poor inverter performance
and will produce abnormal heating leading to risk of insulation melt
down and fire. Normally, the thickness of the cable should be such that
the voltage drop due to the current & the resistance of the length of the
cable should be less than 2%. Use oil resistant, multi-stranded copper
wire cables rated at 90º C minimum. Do not use aluminum cable as it
has higher resistance per unit length. Cables can be bought at a marine /
welding supply store.
Effects of low voltage on common electrical loads are given below:
• Lighting circuits - incandescent and Quartz Halogen: A 5%
voltage drop causes an approximate 10% loss in light output. This is
Installation
Fuse
Positive
because the bulb not only receives less power, but the cooler filament
drops from white-hot towards red-hot, emitting much less visible light.
• Lighting circuits - fluorescent: voltage drop causes a nearly
proportional drop in light output.
• AC induction motors - These are commonly found in power tools,
appliances, well pumps etc. They exhibit very high surge demands
when starting. Significant voltage drop in these circuits may cause
failure to start and possible motor damage.
• PV battery charging circuits - These are critical because voltage
drop can cause a disproportionate loss of charge current to charge a
battery. A voltage drop greater than 5% can reduce charge current
to the battery by a much greater percentage.
!
ATTENTION!
Des dégats causés par un renversement des
polarités n'est pas couverts par la garantie.
Quand vous faites des connexions à la batterie du côté d'entrée, veuillez
assurer que les polarités sont mise du bon côté (Lié le positif de la batterie
à la borne positive de l'appareil et le négatif de la batterie à la borne
négative de l'appareil. Si les polarité de l'entrée sont mise à l'envers,
le fusible CC externe du côté d'entrée va s'exploser et peut causer des
dégâts permanent à l'onduleur.
ATTENTION!
La section d'entrée de l'onduleur a des condensateurs de grande
valeur qui sont connecté aux bornes d'entrées. Tant que le boucle
de connexion d'entrée CC (la borne (+) de la batterie
fusible
la borne d'entrée positive du G4 » la borne d'entrée
négative du G4
la borne (-) de la batterie est complèt, les
condesateurs commençeront à recharger. L'appareil prendra
un courant fort brièvement pour s'alimenter qui va produire
une étincelle sur le dernier contact du boucle d'entrée même si
l'interrupteur ON/OFF du l'onduleur est dans la position OFF.
Assurez que le fusible est insèrer seulement après
que toutes les connexions sont faites dans le boucle
pour que des étincelles se produisent seulement à
l'endroit du fusible
Le flux du courant dans un conducteur est opposé par la résistance du
conducteur. La résistance du conducteur est corrélative à la longueur
du conducteur et inversement corrélatif à son diamètre (l'épaisseur).
La résistance dans un conducteur produit des effects indésirables
comme une perte de tension et une surchaffe. La taille (l'épaisseur)
des conducteurs est classée par le AWG (American Wire Guage). Les
conducteurs qui sont plus épais que la taille AWG #4/0 sont classé par
mCm/kcmil.
le
SAMLEX AMERICA INC. | 25
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