19
20
6.3 DC side wiring
Suggested line length:
Ø
Sunlight will generate voltage on the battery panel.The high voltage
after the series connection may cause life danger.Therefore, before
connecting the DC input cable,you need to cover the battery panel with an
opaque material before operation,and ensure the reverse The DC switch of
the inverter is in the "OFF" state,otherwise the high voltage of the inverter
may cause life danger.
Ø
To avoid electric shock,do not touch the live parts,and connect the
terminals carefully.
Ø
Please make sure that the AC switch has been disconnected before
wiring.
Please
ensure
that
the
following
conditions
are
met
,
otherwise
it
may
cause
a
fire
hazard
or
damage
the
inverter
.
In
this
case
,
the
company
does
not
carry
out
quality
assurance
and
assumes
any
responsibility
.
Ø
The maximum open circuit voltage of each string of photovoltaic
modules shall not exceed 1100Vdc under any conditions.
Ø
PV modules connected in series in each PV string are of the same
specification type.
Ø
The maximum short-circuit current of each PV string must not exceed
26A under any conditions.
Ø
The total output power of all PV strings must not exceed the maximum
input power of the inverter.
Ø
In order to optimize the system configuration,it is recommended to
connect the two inputs with the same number of photovoltaic modules.
Ø
If the inverter output is directly connected to the grid (that is, the
o u t p u t s i d e i s n o t c o n n e c t e d t o a l o w - f r e q u e n c y i s o l a t i o n
transformer),please ensure that the PV string is not grounded.
If the inverter is a specific type of thin-film battery module (PV-
grounded),please connect the low-frequency isolation transformer to the
output terminal before turning it on,otherwise the inverter will be
damaged.
Ø
If
a
stable
non
-
zero
DC
voltage
is
measured
between
the
positive
pole
of
the
photovoltaic
string
and
the
ground,it
means
that
an
insulation
fault
has
occurred
at
a
certain
position
in
the
photovoltaic
string.You
need
to
ensure
that
the
fault
is
repaired
before
continuing
the
wiring
.
Danger
Warning
Inverter model
Cross-section area
Recommendation
Cable outer diameter
MID 17KTL3-X1
10-16
10
40
MID 20KTL3-X1
10-16
10
40
MID 22KTL3-X1
10-16
10
40
MID 25KTL3-X1
10-16
10
40
MID 30KTL3-X
10-16
16
40
MID 33KTL3-X
10-16
16
30
MID 36KTL3-X
14-20
16
30
MID 40KTL3-X
14-20
16
30
Moisture and dust penetration can damage the inverter
Ø
Make sure that the waterproof cable gland is firmly tightened.
Ø
If the cable connector is not installed correctly,the inverter may be
damaged due to the penetration of moisture and dust.All warranty claims
are void.
Note
The MID series inverter has two independent inputs, as shown in the figure below:
Fig 6.5
Note:
MID 17-33KTL3-X(1) (3-channel string); MID 36-40KTL3-X(4-channel string)
(Optional for BAT).
The following points should be concerned when choosing photovoltaic modules:
Ø
The photovoltaic modules of each photovoltaic string are of the same specification
and model.
Ø
The photovoltaic modules of each photovoltaic string are connected in series with
the same number.
Ø
Before connecting the battery panel, please make sure that the DC input
polarity is correct, that is, the positive pole of the photovoltaic module is
connected to the DC input terminal marked "+" of the inverter, and the
negative pole is connected to the DC input terminal marked "-".
Ø
The maximum DC input current and voltage of the inverter shall not
exceed the following limits.
Model
Single maximum input
current
Maximum input voltage
MID 17-33KTL3-X(1)
26A
1100V
MID 36-40KTL3-X
26A
1100V
Note
