When the alcohol is low, the machine will project a red light to warn that it can no longer be used, and it is also convenient for replenishers to know.
When there is insufficient alcohol, the machine will project a red light to remind that it cannot continue to be used, and it is also convenient for the supplementary staff to know.
When the alcohol is insufficient, the machine will project a red light to remind that it can not continue to use, which is also convenient for supplementary personnel to know.<br>