How can I tell when a module or power bank is fully charged?

Answer

On applicable internal-battery modules such as LD150(-I), LD600(-I), ULM1-GP and ULM1-SH, a blue charging indicator changes to green when charging completes. ULM1, ULM3 and ULM3-PDOA standard modules use an external power bank; follow that power bank's indicators, commonly flashing while charging and steady when full. Check the exact device's indicator definitions.