How does the meter work?
Post date: 07-Mar-2016 16:02:57
Let's explain how the soft meter works out the fare using the following tariff as an example.
BY DISTANCE for the first 220yds or part thereof ......$3.25
For any succeeding 220yds or part thereof ................25c ($2.00 per mile)
WAITING TIME - for every 29s or part thereof .............25c (52c per minute)
The meter charges for each section of the taxi ride in advance. This is why the meter shows $3.25, the flag fall, even if you've not moved off yet.
In the conventional mode of operation when the meter is first put into HIRED mode, it charges $3.25, which buys either 220 yards of distance or 29 seconds of waiting time.
If you cover 220yds in less than 29s the meter will increment due to distance, if 29s pass before covering 220yds the meter will increment due to time.
Each subsequent 25c charge will buy either 220 yards or 29 seconds of waiting time. Once again, if you cover 220yds in less than 29s the meter will increment due to distance, if 29s pass before covering 220yds the meter will increment due to time.
There is a speed at which your 25c is used up at exactly the same rate regardless of whether you calculate it by distance (220 yards) or time (29 seconds). This is called the changeover speed and the meter uses up the 25c at the rate of 25c per 29 seconds below it, and 25c per 220 yards above it.
The changeover speed is worked out as:
unit distance / unit time = 220yds / 29s = 7.59 yds/s to convert to mph we multiply by 2.04545 = 15.5 mph
What this means is that, above 15.5 mph, it doesn't make any difference what speed the taxi moves at, it costs 25c for each 220 yards. However, below 15.5 mph, it costs 25c for each 29 seconds.
This is why the same journey can cost a slightly different amount, depending on any waiting time.
If you enable Menu > Settings > Custom preset settings > Charge distance and time concurrently, then every 220yds AND 29s the meter will increment. In this mode of operation, the meter is charging for both distance AND time. This setting is often used with the Use speed determined waiting time setting so that the time meter only ticks when travelling below a specified GPS/OBD speed threshold.