Samlexpower PST-15S-12E Owner's manual - Section 8 |
34 | SAMLEX AMERICA INC.
SAMLEX AMERICA INC. | 35
8.4.5 Recommended Sizes of Battery cables and Fuses
Sizes of cables and fuses are shown in Table 8.2. Sizing is based on safety considerations
specified in British Standard BS 7671. Please refer to “Notes for Table 8.2” for details.
table 8.2 Sizing of Battery Side cables and external Battery Side Fuses
item
(column 1)
Rated
continuous
Dc input
current
(See note
1)
(column 2)
Size of
external fuse
based on Dc
input current
at column 2
(See note 2)
(column 3)
90°c / 194°F copper conductor. Size based on
Ampacity at column (3) or 2%voltage drop,
whichever is thicker (See note 3)
cable Running Distance between
the Unit and the Battery
(cable Routing in Free Air)
Up to 5 ft.
(column 5)
Up to 10 ft.
(column 6)
PST-300S-12E
420A
450A
120 mm
2
or
AWG #4/0
*185 mm
2
or
MCM 350
PST-300S-24E
240A
250A
50 mm
2
or
AWG #1/0
50 mm
2
or
AWG #1/0
* Size is based on 2% voltage drop as it is thicker than the size based on BS 7671 (See Note 3)
noteS FoR tABLe 8.2 - SiZinG oF BAtteRY SiDe cABLeS AnD eXteRnAL
BAtteRY SiDe FUSeS
1) Column 2 indicates the Rated Continuous DC Input Current drawn from the battery.
2) Column 3 indicates size of external fuse not less than the Rated DC Input
Current at Column 2. Next standard capacity is to be used.
3) Columns 5 and 6 indicate cable conductor size that is based on the following
2 considerations. Thicker conductor out of the following 2 considerations has
been chosen:
a) As per guidelines in British Standard BS 7671 - Table 4E 1A (Reference
Method "G" for 2 cables). following have been considered: (i) Ampacity
= the breaker size at Column 3, (ii) Copper conductor with temperature
rating of 90°C / 194°f, (iii) Ambient temperature of 30°C / 86°f and (iv)
Positive and Negative cables in free air, spaced by one cable diameter.
b) Voltage drop across the length of cables has been limited to 2% of 12V /
24V. Voltage drop has been calculated by multiplying the Rated DC Input
Current (Column 2) and the resistance of the total length of Copper
conductor (the total length of conductor has been taken as 2 times the
running distance between the unit and the battery to cover 2 lengths of
Positive and Negative cable conductors).
4) Column 3 indicates the size of external fuse in the battery circuit. It is
mandatory to install this fuse within 7” of the battery Positive terminal to
protect the battery cables against short circuit. Amp rating of the fuse is
based on the following considerations:
a) Not less than the Rated Continuous DC Input Current (Column 2)