[Er.sandeep jain]

Waiting interval
The waiting interval is calculated by the formula :
T = RTT/N
Where,
T = waiting interval
N = number of lifts, and
RTT= round trip time
RTT is the sum of the time required in the following process :
a)Entry of the passengers on the ground floor,
b)Exit of the passengers on each floor of discharge,
c)Door closing time before each floor of discharge, TC
d)Door opening time on each discharging operation, TO
e)Acceleration periods,
f)Stopping and leveling periods,
g)Period of full rated speeds between stops going up, and
h)Period of full rated speeds between stops going down.
It is observed that the handling capacity is inversely proportional to the waiting  time which in turn is proportional to RTT. 

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