Victron energy BlueSolar MPPT 150/70 Manual página 5

3. INSTALLATION
This product may only be installed by a qualified electrical
engineer.
3.1 Location
The product must be installed in a dry and well-ventilated area, as close as possible to -
but not above - the batteries. There should be a clear space of at least 10 cm around
the product for cooling.
The charge controller is intended for wall mounting. For mounting purposes, a hook and
two holes are provided at the back of the casing (see appendix G)
3.2 Battery cables and battery fuse
Do not invert the plus and minus battery connection: this will
permanently damage the charger.
In order to utilize the full capacity of the product, battery cables with sufficient cross section
and a fuse of sufficient current rating should be used.
Some basic formulas for copper cable:
Resistance Rc (m @47° C) of a cable with length L (m) and cross section A (mm²):
Or, with Rc in (Ohm):
Power loss Pc (W) in a cable carrying current I (A):
Power loss Pc relative to solar array output Pv in %:
Cable cross section required to limit relative power loss to α (%):
(with total cable length 2L)
Rc = 20*L/A (1)
Rc =0,02*L/A (2)
Pc = I²*Rc = 0,02*l²*L/A (3)
α = (Pc/Pv)*100 (4)
A = 2*2L*I/(α*V) (5)
or:
A = 2*2L*Pv/(α*V²) (6)
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