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Fronius String Control 250/30 User Manual

Page 24

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22

Pin assignment
for grounded so-
lar modules

In the case of grounded solar modules, only the ungrounded poles of the solar module
strings may be connected to the protected terminals (A).

Example of pin
assignment for
grounded solar
modules

Pin assignment for solar module grounding on the ne-
gative pole

Pin assignment for solar module grounding on the po-
sitive pole

Connecting solar
module strings to
the Fronius String
Control 250/30

(1)

Tightening torque 6.5 Nm

(2)

Tightening torque 1.5 Nm

(3)

Tightening torque 2.0 - 4.0 Nm

Negative solar module grounding

DC-

DC+

B (in)

B' (out) A' (out)

A (in)

Positive solar module grounding

DC+

DC-

B (in)

B' (out) A' (out)

A (in)

(

B

)

(

A

)

(

B‘

)

(

A‘

)

-

+

(

B

)

(

A

)

(

B‘

)

(

A‘

)

-

+

(1)

(2)

1

2