BÜTTNER ELEKTRONIK – Batterie-Control-Booster MT BCB 30/30, MT BCB 40/40, MT BCB 60/40
16
3.5. General installation instructions
• Connect the BCB according installation
type!
• Comply with cable cross-sections and
lengths acc. table 1
• Pay attention to polarity
• Fuse installation close to the battery
• First connect BCB, at last the batteries!
• Adapt the mains plug from the BCB to
the mains installation in the motorhome
(socket).
The large power terminals are used to
connect ground and charging cabling. Only
strip the ends of the battery cables on the
BCB – do not use bootlace ferrules (cage
clamps)!
Stripping length: approx. 12 mm
Terminal COM
• Connect the negative pole of the BOARD
battery or to the chassis ground.
Note: If a battery computer is available,
connect it to the central earth point of the
measuring shunt according to the instruc-
tions!
• Connection: max. 16 mm
2
Note
i
An additional ground link “-Batt.”,
between both minus poles of star-
ter- and board battery as shown, is only
required for:
• Isolated motorhome constructions
• To avoid galvanic equalizing currents in
lightweight vehicle chassis
Terminals + BORD, + START
• Connect the +12 V cable of the board
battery to the +BORD terminal with the
correct polarity.
• It is essential to connect the +12V cable of
the starter battery to the +START termi-
nal with the correct polarity! Attention:
Reverse polarity on the starter battery
can lead to serious damage of the BCB!
• Terminal spec.: max. 25 mm
2
3.6. Connection of – Com, + BORD, + START
MT BCB 30/30
Cable
cross-
section
Cable
length
+ START
at isolated
construc-
tions:
Cable
length
-Batt.
Si. II
Cable
protection
Cable length
– Com.
to board
battery
Cable
length
+ BORD
Si. I
Cable
protection
4 mm²
–
–
–
0.5 – 1.5 m
0.5 – 1.5 m
40 A
6 mm
2
to 5 m
to 5 m
50 A
1.0 – 2.5 m
1.0 – 2.5 m
40 A
10 mm
2
to 8 m
to 8 m
50 A
2.0 – 4.0 m
2.0 – 4.0 m
40 A
16 mm
2
to 12 m
to 12 m
50 A
3.0 – 6.0 m
3.0 – 6.0 m
40 A
Table 1: Recommended cable cross-sections for different lengths as well as protections
for the assignment of the 3 large power connection terminals – Com, + BORD, + START
for full charging power while driving
