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INSTALLATION AND OPERATION MANUAL FOR CIGS SOLAR MODULES Q-CELLS SE - EUROPE
Ensure that the following requirements for a functional grounding are met:
• The negative pole of the solar module array is to be connected to ground.
• By using a framed Q.SMART module a hard grounding is only permitted when this is in
accordance with local regulations and abides by the requirements of the respective inverter
manufacturer.
• A resistor is used which is rated for the expected power (P=U²/R).
• A maximum of 150 module strings in the module array can be connected to the inverter.
• Only inverters are used for which the manufacturer provides a ground kit complying with the
above provisions.
• It must be ensured that the PV modules have
no
negative potential with respect to the ground
potential.
• Do not connect the modules to system with positive grounding or central point grounding.
If it is essential to functionally ground a PV generator as a result of our specifications or local
regulations, the grounded conductor should be monitored by a safety device to ensure that:
a) ground fault currents > 30 mA are prevented (e.g. by installing a > 35 k
Ω
resistor for a
1000 VDC maximum-voltage system) or
b) ground fault currents > 50 mA don‘t exceed a length of time of 0.4 s are detectable and
preventable with certainty.
A simple ground fault safety device must not be used..
Specifications for topologies:
• Transformerless inverters with flying inductor topologies, on which the negative pole of the PV
generator is permanently grounded, can be used anywhere with Q.SMART modules.
• Transformerless inverters with quiet-rail topology, on which the potential of the negative
generator pole can be fixed to positive values by appropriate selection of the string voltage,
can be used anywhere with Q.SMART modules. In regions requiring functional grounding,
the system potentials are to be measured at the time of start-up. It is permissible to operate
the system only when the negative generator pole has a positive potential with respect to PE.
Note: Further information regarding functional grounding and drawings with exemplary wiring
diagrams can be found in the annex.
Ground each of the framed modules with Parker screws (according to DIN 7981, material: A2,
size: 4.2 mm x 16 mm) to the grounding points indicated in Figure 1. Attach the screw as
shown in Figure 5.
FIGURE 5:
Attachment of the grounding
FUNCTIONAL GROUNDING
SAFETY BONDING
1
2
3
4
1
1 Stainless Parker screw
2 Stainless washer (cable lug)
3 Stainless serrated lock washer
4 Module frame
