6 Installation
Installation and Operation Manual for RPI M50A
42
6.5 Connecting to the solar modules
(DC)
Read chapter
“5. Planning the installa-
tion”, p. 18
before
you start installa-
tion.
6.5.1 Safety instructions
DISCONN AC/DC
OFF
ON
DANGER
Risk of death or serious injury from
electrocution
Potentially fatal voltage may be applied to
the DC connections of the solar inverter.
When light is falling on solar modules,
they immediately start producing energy.
They do so, even when the sun is not
shining.
►
Never disconnect the solar modules
when the solar inverter is powered.
►
First switch off the grid connection
so that the solar inverter cannot feed
energy into the grid.
►
Turn the AC/DC isolating switch to
position
OFF
.
►
Make sure the DC connections cannot
be accidentally touched.
NOTICE
Improperly sized PV array.
An improperly sized PV array can
cause damage to the inverter.
► Consider the technical specifi ca-
tions of the inverter (input voltage
range, maximum currents and maxi-
mum input power, see
“13. Techni-
cal data”, p. 105
) when planning
the size of the PV array.
NOTICE
Penetrating humidity.
Humidity can penetrate through unused
DC connectors into the inverter.
►
To ensure protection degree IP65,
protect all unused DC connectors
with the caps delivered with the
inverter.
NOTICE
Machine and equipment damage
may occur.
Exceeding the maximum current per
DC input can cause an overheating of
the DC inputs.
►
Always consider the maximum cur-
rent of the DC inputs when planning
the installation.
6.5.1.1 Polarity of the solar modules
Check the polarity of the DC voltage before you con-
nect the solar modules. The negative DC pole of the
string is connected to the DC-MINUS connector; the
positive DC pole to the DC-PLUS connector, see
“Fig.
6.22: Considering the polarity of the solar modules”,
p. 42
.
DC INPUT
DC 1
DC 2
–
+
–
+
+
+
–
Fig. 6.22: Considering the polarity of the solar mod-
ules
6.5.2 Cable specifi cation
Cable colors
Use a red cable for DC+ and a black cable for DC–.
Fig. 6.23: Colors for DC cables
