Communication cable check

A communication cable check means inspecting the communication cable and its terminals for any abnormality, then fixing what you find so the connection is reliable. Sungrow manuals call for it when the inverter raises a meter communication abnormal alarm or an inverter parallel communication alarm. If the cable and terminals look fine, reconnect the meter communication cable. If the alarm still persists after that, contact Sungrow customer service. On CPS three-phase inverters, the CAN communication alarm Warn0020 points to poor contact at the terminal blocks of the internal communication wires. For that CPS alarm, first watch for a few minutes to see if it clears by itself. Then restart by switching the AC and DC switches off and on again, waiting between steps so stored energy can discharge. Call after-sales service if the alarm returns. Keep communication cables short: Sungrow warns that runs longer than 10 m can lose the connection. A single inverter needs only one RS485 cable. To prevent problems, joint and seal communication cables properly so they stay watertight, and check all cable connections during routine maintenance, tightening or replacing them as needed.

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• sentence 3: support check: partial - Reconnecting the meter cable and contacting service if the alarm persists are stated, but the measure is to reconnect after the check (fixing any abnormality), not specifically 'if cable looks fine'; the sequence is broadly consistent but the condition is slightly reframed.
• sentence 4: support check: partial - Warn0020 CAN Comm Abn with poor contact at internal communication wire terminal blocks is stated, but the passages do not mention CPS three-phase inverters by name.
• sentence 6: support check: partial - The notice says cables over 10 m risk disconnection and a single inverter needs one RS485 cable, but the passages do not attribute the warning to Sungrow by name.
• sentence 4: review: partial - The CPS row ties Warn0020 CAN Comm Abn to poor contact at the terminal blocks of internal communication wires, but nothing in the passages scopes it to 'three-phase' inverters. -->