Technical Support wrote:
The LED's will light up within 10-15 seconds after turning on the inverter. Assuming a fresh battery charge, all three lights will come on. This is with the inverter on and no load. As flashes are fired, the LED's will sequencially go off. After a fair bit of shooting, returning the inverter to a no draw state (i.e. the lights are not being recycled), the LED's will come back on. This may take longer than 15 seconds, especially if 4 or more of those seconds are under heavy load (recycling). If the model lamp is on, the LED's may not recover until the model lamp is turned off, as well I do not know what the power draw is on an Elinchrom which can affect the time it takes for the LED's to recover.
The most accuracy from the LED guage is with the inverter on, no load, and with sufficient time for the LED's to register.
Thank you for the explanation.
Dave F.