12
Quick Installation Guide for Solar Power Inverter M125HV EU V1 EN 2019-04-01
AC cable
ATTENTION
Danger of a cable fire.
Bending and twisting causes damage to the
inner structure of the conductor, which leads to
punctiform increase in electrical resistance. This
can result in an overheating of the conductor
and destruction of the insulation.
► When bending and twisting cables or
conductors, always comply with the
manufacturer’s instructions.
Min./max. Conductor cross-section
● Copper cables
50 ... 185 mm
2
● Aluminum cables
95 ... 185 mm
2
AC cable gland
The inverter has 1 AC cable gland with 1 cable feed-through.
Min./max. Cable diameter
33.0 ... 76.8 mm
Notes on calculating the cable cross-section
Consider the following factors when calculating the cable diam-
eter:
● Cable material
● Temperature conditions
● Cable length
● Installation type
● Voltage drop
● Loss of power in the cable
Always follow the IEC 60364-5-52 requirements and your coun-
try-specific installation instructions.
France: Follow the installation instructions of UTE 15-712-1. This
standard contains the requirements for minimum cable diameters
and for avoiding overheating due to high currents.
Germany: Follow the installation instructions of UTE VDE 0100-
712. This standard contains the requirements for minimum cable
diameters and for avoiding overheating due to high currents.
Handling aluminum conductors during installation work
The special properties of aluminum must be taken in to consider-
ation when using aluminum:
● Aluminum "flows", i.e. it gives way under pressure.
● A thin non-conductive oxide layer forms within a few min-
utes on de-insulation, which increases the contact resis-
tance between the conductor and cable lug.
● The specific conductivity and hence the current carrying
capacity is approximately one third less than that of copper.
ATTENTION
Extreme temperature rise at the clamping
point
If the contact resistance between the aluminum
conductor and cable lug is too high, the clamp-
ing point can become very hot and even catch
fire in extreme cases.
To ensure a safe and reliable contact,
always
perform the following work steps:
► Keep the installation location as free
as possible from moisture or corrosive
atmospheres.
► Connect the aluminum cables quickly.
► Mechanically clean the stripped end of the
aluminum conductor (using for instance
a knife blade to scrape off the oxide
layer), then immediately dip the aluminum
conductor into acid-fee and alkaline-free (=
neutral) Vaseline and straight away insert it
into the cable lug.
► Tighten the nut on the cable lug with the
maximum permissible tightening torque.
Cable requirements
