Fronius String Control 250/25, Operating Instructions Manual

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16
NOTE! When connecting fewer than 25 solar module strings, we
recommend assigning an equal number of DC cables to the
measuring channels as much as possible.
For example: When connecting 15 solar module strings, connect
3 DC cables per measuring channel. If possible, leave individual
terminals free between the DC cables.
NOTE! When connecting Aluminium cables:
- consider national and international rules for connecting Alumi-
nium cables
- consider technical information of the cable manufacturer
Notes for
Connecting
Solar Module
Strings to the
Fronius String
Control 250/25 NOTE! Connecting the DC wiring with the
wrong polarity may cause damage to the
Fronius String Control 250/25.
Check both the polarity and the open
circuit voltage.
The DC Voltage must not exceed 600 V, regard-
less of temperature.
Terminal Assi-
gnment with
Grounded
Solar Modules
DC- DC+
B (in) B‘ (out) A‘ (out) A (in)
DC+ DC-
B (in) B‘ (out) A‘ (out) A (in)
With grounded solar modules, the ungrounded poles of the solar module
strings must be connected to the fused terminals (A).
Negative Grounding
Positive Grounding