Fronius String Control 250/25 DCD DF Instructions De Service page 59

Table of contents
General .............................................................................................................................. 3
Device Concept ............................................................................................................. 3
Functional Principle ....................................................................................................... 3
Inverter ........................................................................................................................... 4
Other System Requirements.......................................................................................... 4
Intended Use ................................................................................................................. 4
Scope of Supply ............................................................................................................. 4
Optional ......................................................................................................................... 4
Technical Data ............................................................................................................... 5
Abbreviations and Descriptions Used ............................................................................ 5
Warning Notices on the Device ..................................................................................... 6
Product Description ............................................................................................................ 7
Safety............................................................................................................................. 7
Fronius String Control 250/25 DCD DF Device Description ........................................... 7
Fronius String Control 250/25 DCD DF Installation .......................................................... 10
Dowels and Screws ..................................................................................................... 10
Installation Position ...................................................................................................... 10
Selecting a Location .................................................................................................... 10
Safety............................................................................................................................ 11
Fronius String Control 250/25 DCD DF Installation ...................................................... 11
Installing Metric Screw Joints on the Fronius String Control 250/25 DCD DF .................. 12
Preparation .................................................................................................................. 12
General ........................................................................................................................ 12
Recommended Sequence for Inserting the Metric Screw Joints ................................. 12
Installing Metric Screw Joints on the Fronius String Control 250/25 DCD DF ............. 13
Tightening Torque for Metric Screw Joints ................................................................... 13
Connecting Solar Module Strings to the Fronius String Control 250/25 DCD DF............. 14
Safety........................................................................................................................... 14
Notes for Connecting Solar Module Strings to the Fronius String Control 250/25 DCD
DF ................................................................................................................................ 14
Terminal assignment for grounded solar modules ....................................................... 15
Connecting Solar Module Strings to the Fronius String Control 250/25 DCD DF ........ 16
Connecting the Fronius String Control 250/25 DCD DF to the Inverter............................ 17
Safety........................................................................................................................... 17
Preparation .................................................................................................................. 17
Connecting the Fronius String Control 250/25 DCD DF to the Inverter ....................... 18
Criteria for the Proper Selection of String Fuses .............................................................. 19
General ........................................................................................................................ 19
Criteria for the Proper Selection of String Fuses ......................................................... 19
Effects of Using Underrated Fuses .............................................................................. 19
Fuse Recommendations .............................................................................................. 19
Application Example .................................................................................................... 20
Fuses ........................................................................................................................... 20
Inserting String Fuses ...................................................................................................... 21
Safety........................................................................................................................... 21
Selecting String Fuses ................................................................................................. 21
Inserting String Fuses .................................................................................................. 21
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