Checking The Dc Voltage; Switching On The Supply Voltage And The Ac Disconnection Unit - SMA MEDIUM VOLTAGE POWER STATION 500SC-JP System Manual

6 Commissioning
6.4.6

Checking the DC Voltage

Danger to life due to electric arcs if measuring device is not connected correctly
If the measurement points are incorrectly contacted, this can cause an electric arc. Electric arcs can result in death or
serious injury.
• Select the appropriate measurement range on the measuring device.
• Wear suitable personal protective equipment for all work on the device.
• Select correct measurement points.
Damage to the inverter due to excessive DC voltages
The DC voltage of the PV array must not exceed the maximum voltage of the inverter.
• Make sure the maximum voltage is no more than 1,000 V.
Procedure:
1. Measure the DC voltage for each input and record it in the commissioning report. Use the DC+ and DC‒
connection brackets as measuring points.
2. Check that the DC voltages do not exceed the maximum DC voltage of the inverter.
If the DC voltages differ from one another or exceed the maximum DC voltage, make sure that the cabling of the
PV modules has been configured in accordance with the circuit diagram.
3. Make sure that the polarity of each input is correct.
4. Measure the DC voltage for each non-grounded pole to ground and record in the commissioning report. Use the
connection brackets of the ungrounded terminal and the grounding busbar as check points.
☑ There is a measurable voltage drop.
✖ There is no measurable voltage drop?
A ground fault is present.
• Eliminate the ground fault.
6.4.7

Switching On the Supply Voltage and the AC Disconnection Unit

1. Close the measurement and disconnect terminals.
78 MVPS22JP-SH-en-11
SMA Solar Technology AG
System Manual