SMA SC 500CP-US - Manual (Page 94)

16 Commissioning SMA America, LLC
94 SCCP-US-IA-US_en-41 Installation Manual
16.4 Checking the Voltages on the Inverter
16.4.1 Checking the DC Voltages
1. Measure the DC voltage for each input and record it in the commissioning report.
2. Compare the DC voltages. The voltages must be approximately the same and must not exceed the maximum
DC voltage of the inverter.
3. Check that the polarity of each input is correct. Correct if necessary.
4. Measure the DC voltage for each positive terminal to ground and record in the commissioning report.
☑ Voltage drops out.
✖ Is a stable value present?
A ground fault has occurred.
• Eliminate the ground fault.
16.4.2 Checking the AC Line Voltage
1. Check the line voltage for the right-hand rotating magnetic field. Correct if necessary.
2. Measure the AC voltage between the line conductors and record in the commissioning report.
– A - B
– A - C
– B - C
☑ The AC voltage is approximately the same as the inverter nominal voltage.
✖ Does the AC voltage deviate significantly from the nominal voltage of the inverter?
• Have the transmission ratio of the medium-voltage transformer adjusted by an authorized person.
16.4.3 Checking the External AC Power Supply Voltage
The inverter draws electric current for its internal power supply via the optional external voltage supply. You have to
measure and record the external supply voltage.
In the inverter cabinet All 7.4 ft.-lbs (10 Nm)
'$1*(5
Danger to life due to electric arcs if the multimeter is not connected correctly
Contacting the measurement points incorrectly can cause an electric arc. Death or serious injury may result from an
electric arc.
• Wear Hazard Risk Category 2 personal protective equipment.
• Select the appropriate measurement range on the multimeter.
• Select the correct measurement points.
/05*$&
Damage to the inverter due to high DC voltages
The DC voltage of the PV array must not exceed the maximum voltage of the inverter.
• V
PV
= 1,000 V
Protective covers Torque