Huawei SUN2000-75KTL Series User Manual page 79

SUN2000-(75KTL, 100KTL, 110KTL, 125KTL) Series
User Manual
Step 4 Tighten the lock nuts on the positive and negative connectors.
Step 5 Use a multimeter to measure the voltage between the positive and negative
terminals of the PV string (measurement range no less than 1100 V).
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Step 6 Use an insulation resistance tester to test the insulation resistance between the
PV– cables and the ground: Add 1500 V DC voltage between the PV– cables and
the ground and check the insulation resistance.
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Step 7 Insert the positive and negative connectors into the corresponding DC positive and
negative input terminals of the solar inverter.
Issue 15 (2023-01-31)
If the voltage is a negative value, the DC input polarity is incorrect and needs
correction.
If the voltage is greater than 1100 V, too many PV modules configured to the
same string. Remove some PV modules.
If the insulation resistance is greater than or equal to 1 MΩ, it is normal.
If the insulation resistance is less than 1 MΩ, troubleshoot the cable
insulation.
Figure 5-22 Testing the insulation resistance
NO TE
You can use a self-made tool to connect all PV– cables together through an adapter to
test the insulation resistance between all PV– cables of a device and the ground at a
time.
Figure 5-23 Testing the insulation resistance between all PV– cables and the
ground
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5 Electrical Connections
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