If the LED fails to illuminate or stays on for less than 5 seconds, the capacity is below 50% and requires a full recharge cycle. Above 50% Capacity: Charge for 8 hours. Below 50% Capacity: Charge for 16 hours.
According to the PS-855B documentation on Scribd , technical personnel should follow these specific steps: ps-855b maintenance manual
Once a year, a full battery capacity test is required to determine the remaining life of the cells. Essential Maintenance Procedures If the LED fails to illuminate or stays
Batteries must be left in a discharged state, as this causes permanent damage. According to the PS-855B documentation on Scribd ,
With no external power applied, press and hold the button for 5 seconds.
A condition check must be performed every quarter or half-year to verify the unit's operational status. This is similar to a "Preflight Check" and ensures the unit is ready for emergency deployment.
The unit can reach 50% capacity within one hour at 25°C under normal flight conditions.