Intelligent Temperature-Control Technology; Insulation Monitoring Function; Introduction; Simple Troubleshooting - Sungrow SG2500-MV System Manual

10 Inverter Functions
10.8

Intelligent Temperature-Control Technology

Inverter will continuously detect the IGBT temperature and adjust the fan speed accordingly.
When the module temperature is low, inverter will decrease the fan speed to lower the
device noise and decrease the device operation consumption. As the module temperature
increases, inverter will increase the fan speed for well ventilation.
The intelligent temperature-control technology can synchronize the speed of fan and
temperature of the IGBT module and thus optimize the module temperature and other
conditions.
10.9

Insulation Monitoring Function

10.9.1 Introduction

Insulation resistance is an important parameter related to safety operation. If the insulation
resistance is low, the direct contact protection and indirect contact protection may be failed;
meanwhile the fault current against the ground and the short circuit caused by low
insulation resistance may lead to electric fire, device damage or even physical hazards.
Sungrow's inverter is equipped with insulation resistance monitoring function to detect the
system insulation resistance in real time. If the resistance is detected to be low, it will send
alarm at the first time to remind the user and prevent potential hazards.

10.9.2 Simple Troubleshooting

Regardless of the inverter setting, when the insulation resistance is below the threshold
(settable from the LCD display), inverter will send alarm signal and the Operation LED will
turn to yellow. After receiving the "low insulation resistance" alarm signal, user should stop
the device and check the specific insulation resistance from the LCD screen
"Function/Run-information/Real time data".

If the insulation resistance recovers to normal, the fault loop is in the AC side.

If the insulation resistance is still low, the fault loop is in the DC side.

No matter is fault is in the DC side or in the AC side, a thorough checking and
troubleshooting after the system is power down is necessary.
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SC "I-V"Curve
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MPP
"P-V"Curve
Fig. 10-5 MPPT
U
MPP
Voltage(V)
System Manual
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MPP
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