Measurement Computing LogBook Series - Manual (Page 100)

6-12 GPS and Serial Device Data Collection 958396 LogBook User’s Manual
Using Serial Channels in Calculated Channels
Calculated channels and the LogBook’s ability to use them to define trigger and stop events is a very
powerful feature. This feature extends to the serial channels, which provide time-of-day data plus
information from GPS and general serial devices.
Example Application #1
An RS-232 scale is being used to measure the weight of a liquid fuel while a thermocouple measures engine
temperature. The LogBook is to trigger when the temperature exceeds 200F OR when fuel weight is less
than 30Kg. This is represented by the calculation function seen in the following figure, where:
(P1_CH00_2>200) Or (SER_CH00<30)
The calculated channel shown yields a
true/false output that is both recorded
and used as the trigger source.
Example Application #2
An oven is being monitored by several thermocouples attached to a LogBook. The LogBook is to trigger
whenever the temperature of the oven exterior is above 50C or at 9:00AM each day. The following
calculate channel equation yields a true/false output that is both recorded and used as the trigger source.
(P1_CH00_2 > 50) Or (SER_CH03 > 9)
The serial channel, SER_CH03, is assigned the Channel Type, TOD_Hour