Alternating flashing on the EC-Base LEDs means that the electrical circuit is complete but no LRE link is established. Either the cable is partially damaged, long, has mismatched impedance couplers, a bridge tap or T split, or is being subjected to high amounts of EMI. Re-terminating couplers can help remedy this problem.
You’ll find additional resources like the Datasheet, Admin Guide, A&E spec sheet, etc on the product page here.
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