Inspection Before Powering Up; Inverter; Pv Array; Checking Grid Voltage - Sungrow SG1100UD System Manual

System Manual
7.3

Inspection Before Powering Up

7.3.1 Inverter

• Ensure that the AC and DC switches and all internal miniature circuit breakers are
disconnected.
• Check and ensure that the emergency stop button is released .
• Check various upstream and downstream electrical switches and buttons, as well as
those on the inverter, to make sure that they can be operated flexibly and meet the
requirements.
• Check whether the film at the air inlet and outlet are removed.
• Check whether the pressure relief screw has been removed.
• Check whether the fuse is installed in the AC SPD.

7.3.2 PV Array

The DC side voltage shall not exceed the maximum DC voltage allowed for the inverter. Oth-
erwise, the inverter may be damaged and even cause safety accidents.
To ensure the stable and efficient operation of the whole system, it is recommended that bat-
teries connected to an inverter should be of the same type and from the same manufacturer,
and the number of batteries connected in series should be the same.

7.3.3 Checking Grid Voltage

• Measure accurately the grid 3-phase line-to-line voltages: L1-L2, L1-L3, and L2-L3.The
voltages should not exceed the grid permissible voltage and the three phases are in
balance.
Adjust the transfer ratio of the transformer by qualified personnel if the grid voltage
deviation is large.
• Measure and record the grid frequency. Measured data should not exceed the grid per-
missible frequency.
• Measure the THD and check the curve if possible. The inverter will stop running if the
THD is serious.
• Record accurately all the measured data.
7.4

Powering Up Steps

Step 1 Turn on the maintenance switch QS2 of all inverter units, the maintenance switch QS3 at the
bottom of the inverter unit.
Step 2 Click "Overview" → "General Information" and click "Shutdown" in the "Shortcut
Menu" on the Web page to shut down the inverter.
Step 3 Check and ensure that the "Access Protection Enabling" switch is off on the Web page.
7 Powering up and Powering down
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