Intelligent Temperature-Control Technology; Insulation Monitoring Function; Introduction; Simple Troubleshooting - Sungrow SG2500U-MV System Manual

10 MV Station Functions
10.8

Intelligent Temperature-Control Technology

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

Insulation Monitoring Function

10.9.1 Introduction

Insulation resistance is an important parameter related to safe 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 MV Station 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 MV Station setting, when the insulation resistance is below the threshold
(settable from the LCD display), MV Station 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. 10-4 MPPT
U
MPP
Voltage(V)
System Manual
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MPP
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