Calculated Industries 9126 - Manual (Page 14)

Time Conventions
When you are dealing with time, there
are actually two kinds of time values
that must be considered:
1. Points in Time: 9:22 AM, 5 PM
2. Time Periods: 37 Minutes, 45 Seconds
The time math rules are as follows:
Addition
Period + Period = Period
3 Hrs. + 22 Min. = 3
HR
22
MIN
Point + Period = Point
9 AM + 22 Min. = 9:22
AM
Point + Point = Error
Note:
You cannot add two points in time as
the result would be meaningless.
Subtraction
Period – Period = Period
3 Hrs. – 22 Min. = 2
HR
38
MIN
Point – Period = Point
9 AM – 22 Min. = 8:38
AM
Point – Point = Period
9 AM – 8:30 AM = 30
MIN
Period – Point = Error
Note:
When subtracting one point in time
from another, it’s best to enter the “later”
time first, then subtract the earlier time.
14 – Time Master ™ II