1 2 3 - Torqeedo

Cables, switches, fuses
Torqeedo connection cable with 35mm 2 cross sectional area.
Background knowledge: Ohm’s law and cable power dissipation
According to Ohm’s law, the power dissipation of a cable is proportional to its electrical resistance and is related to the square
of the electricity flowing through it. More simply expressed: double the current leads to a quadrupling of loss, and ten times the
current leads to one hundred times the loss.
For safety reasons, boats operate in the low-voltage range. That is why even in electrical drives between 2,000 and 3,000 watts
input power, the peak current flow amounts to 80 to 100 amperes.
In comparison: A 1,100 watt electric drill draws 5 amps from a 220 V socket. If you were to operate an electrical drive using
standard household cable then there would be a power loss of approx. 15% caused simply by the cable resistance. In order to
keep losses at a minimum and to avoid the danger of local overheating, manufacturers have to reduce the cable resistance to a
minimum. In order to do so, there are two approaches: the distance between the battery and the motor can be minimized, and a
large diameter cable can be selected.
Catalogue 2007
11