Tachymeter - Seiko 6M25 Instruction Manual

TACHYMETER

(for models with tachymeter scale on the dial)
To measure the hourly average speed of a vehicle
Use the stopwatch to determine
1
how many seconds it takes to go
1 km or 1 mile.
Tachymeter scale indicated by
2
Second hand gives the average
speed per hour.
* Tachymeter scale can be used only when the time required is less than 60 seconds.
Ex. 2: If the measuring distance is extended to 2 km or miles or shortened to 0.5 km or miles
and Second hand indicates "90" on tachymeter scale:
"90" (tachymeter scale figure) x 2 (km or mile) = 180 km/h or mph
"90" (tachymeter scale figure) x 0.5 (km or mile) = 45 km/h or mph
18
Ex. 1 Ex. 1
Second hand:
40 seconds
Tachymeter scale: "90"
"90" (tachymeter scale figure) x 1 (km or mile)
= 90 km/h or mph