请问下列是什么意思?
ratio of the emergency luminous flux of the lamp supplied by the emergency ballast to the luminous flux of the same lamp operated with appropriate reference ballst at its rated voltage and frequency The emergency ballast lumen factor is the minimum of the values measured at the appropriate time after failure of the normal supply and continuously to the end of the rated time duration
mention of whether the ballast is suitalble for use only on battery not having a trickle or intermittent re-charging circuits