Installation Manual

9. Applyheatshrinkinsulationtothelugsbarrels.
10. Connectthewirestotheterminalblockswithapropertoolaccordingtothelabelsontheterminals.
11. Tightenthescrewsofeachterminalwithatorqueof15N*m/12lb*ft.
Figure 25: Wire connections to terminal block
Wire type Connect to terminal
Line 1 L1
Line 2 L2
Line 3 L3
Neutral N
12. Placethecoverontheterminalblockandpushuntillyouhearaclick.
Connecting the Strings to the Connection Unit
YoucanconnectsystemswithmultipleDCstringsinparalleltotheDCinputterminalsoftheConnection
Unit.
NOTE
The DC bus of each unit is separate and not shared for all units. Therefore in addition to following the
inverter design rules, each unit should follow the unit design rules as detailed in Technical
Specifications.
InvertersmayhaveadifferentnumberofpairsofDCinputterminals,dependingontheinverterpower
rating.Ifmorestringsarerequired,theycanbeconnectedinparallelusinganexternalcombinerbox
beforeconnectingtotheConnectionUnit;stringsconnectedtodifferentunitscannotbecombined.
Whenconnectingmultiplestrings,itisrecommendedtorunseparatecircuitstotheConnectionUnitor
topositionthecombinerboxneartheConnectionUnit.Thissimplifiescommissioningbyallowingtesting
andservicingneartheinverter.
To connect the strings to the Connection Unit with glands:
1. Strip5⁄16''(8mm)oftheDCwireinsulation.
2. InserttheDCconduitintotheDC-sideopeningontheConnectionUnit(leftsideatthebottomofthe
ConnectionUnit).
3. Equipmentgrounding:ConnecttheDCequipmentgroundconductortotheequipmentgrounding
terminalblock(bus-bar)intheConnectionUnit.
NOTE
Functional Electrical Earthing of DC-side negative or positive is prohibited because the inverter has no
transformer. Equipment grounding of exposed conductive surfaces in the array is required per the
NEC.
4.
ConnecttheDCwirestotheDC+andDC-terminalblocks,accordingtothelabelsontheterminals.
or;connecttwowires(DC+andDC-)perstring:
a. Useastandardflat-bladescrewdrivertoconnectthewirestothespring-clampterminals.The
screwdriverbladeshouldfitfreelyintheterminalopening.Toolargeabladecancracktheplastic
housing.
Chapter 4: Connecting the AC and Strings to the Connection Unit
Three Phase Inverter with synergy technology Guide MAN-01-00401-1.1
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