3 red led is glowing continuously, 1 checking the pv generator for a ground fault, Red led is glowing continuously – SMA SMC 6000TL Installation User Manual
Page 68: Checking the pv generator for a ground fault, In section 9.3.1 ”checking the pv generator
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SMA Solar Technology AG
68
SMC6-8TL-IEN101040
Installation Guide
9.3 Red LED is Glowing Continuously
If the red LED of the status display is continuously on during operation, there is either a ground fault
in the PV generator or at least one of the varistors for the overvoltage protection is defective.
9.3.1 Checking the PV Generator for a Ground Fault
1. Disconnect the inverter from both the DC and AC connections as described in section
7.2 ”Opening the Inverter” (page 52).
2. Measure the voltages between the plus pole of an
individual string and minus pole of an individual
string against the ground potential.
☑ If voltage is found, there is a ground fault in the
corresponding string.
Watchdog
Watchdog-Srr
Internal program run fault.
Corrective measures
• If this fault occurs often, contact the SMA Serviceline
NOTICE!
Excessive voltages can destroy the measuring device.
• Only use measuring devices with a DC input voltage range up to at least 700 V.
DANGER!
Risk of lethal electric shock.
If a ground fault occurs, the PV generator may carry high voltages.
• Do not touch the frame of the PV generator.
• Wait until no voltage can be measured.
• Do not connect strings with ground faults to the inverter.
Message
Description and corrective measure