SMA SC 400HE Installation - Manual (Page 94)

Commissioning SMA Solar Technology AG
94 SCxxxHE-IEN104432 Installation Guide
Checking the Internal AC Power Supply
• Measure and record AC voltages
– L1-L2
– L1-L3
– L2-L3
– L1-N
– L2-N
– L3-N
Checking DC Voltages
• Measure and record the DC voltage for every input.
• Check that the polarity of each input is correct.
• Check the correct polarity of the DC busbar in the Sunny Central.
• Measure the voltage for every input and every pole to ground.
– If the value is stable, a short to ground is present.
• Measure and compare the voltages of the individual inputs. The voltages must be
approximately equal.
• The voltage must not exceed the maximum DC voltage of the inverter.
WARNING!
Danger of arcing if the measuring device is incorrectly connected.
• Ensure that the measuring device is connected correctly.
• Select the appropriate measuring range.
NOTICE!
Damage to the Sunny Central due to high DC voltages
The DC voltage of the photovoltaic generator must never exceed the maximum permissible
inverter voltage.
• U
PV
= 1 000 V