Samlex Europe PST-15S-12E, Руководство пользователя

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Connection from the batteries to the DC input side of the inverter – cable and
fuse sizes
The 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 pro-
duces undesirable effects of voltage drop and heating. Thus, thicker and shorter conductors
are desirable. The size (thickness / cross-section) of the conductors is designated by Mmq.
Please note that a higher Mmq denotes a thicker size of the conductor up to 120Mmq.
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.
Use oil resistant, multi-stranded copper wire cables rated at 90 ¼ C minimum. Do not use
aluminium cable as it has higher resistance per unit length. Cables can be bought at a
marine / welding supply store.
The cables from the battery to the inverter should be protected by a suitable, very fast
acting DC fuse. Use a DC fuse of the appropriate capacity in line with the positive cable.
The fuse should be within 50 cm from the battery.
The following size of cables and fuse are recommended. The distance shown is the
distance between the battery and the inverter. The recommended size of the cables will
limit the voltage drop to approximately 2% ( The length of the cable for calculating the
voltage drop has been taken as 2 times the distance between the inverter and the battery
assuming that two ( one positive and one negative)cables are used for the connection )
Distance up to 120cm Distance up to 180cm Ampere rating of fuse
PST-15S-12E 4 Mmq 6 Mmq 20 A
PST-15S-24E 2,50 Mmq 4 Mmq 10 A
PST-30S-12E 4 Mmq 10 Mmq 40 A
PST-30S-24E 2,5 Mmq 6 Mmq 20 A
PST-60S-12E 25 Mmq 35 Mmq 125 A
PST-60S-24E 16 Mmq 25 Mmq 6 A
CAUTION! The input section of the inverter has large value capacitors connected
across the input terminals. As soon as the DC input connection loop
(
➪
fuse
➪
in
➪
inverter battery negative) is completed,
these capacitors will start charging and 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 the sparking is limited to the fuse area.
Using proper DC cable termination
The battery end and the inverter end of the cables should have proper terminals
that will ensure a firm and tight connection.
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