Campbell LoggerNet, Инструкция по эксплуатации

Страница: 524 / 580

Appendix C. Table-Based Dataloggers
Example:
A CR10X-TD is to be used to monitor three thermocouples. Each hour a
temperature for each of the three thermocouples is to be stored. The table has
five fields: DATE_TIME, RECORD #, TEMP1, TEMP2, TEMP3.
The program is written so that each hour an Instruction 84, Table Data,
generates a new “record” in the data table. This hourly table would then be
organized as follows:
DATE_TIME RECORD # TEMP1 TEMP2 TEMP3
2002-01-27 10:00:00 14 23.5 24.6 28.2
2002-01-27 11:00:00 15 24.2 22.4 23.4
Only the hourly data triggered by the Instruction 84 above would be written to
this table. If other table data instructions existed, the output for these tables
would be written to their own tables.
Data tables can also be event driven rather than interval driven. That is, a new
record is stored when a specified event occurs rather than based on time.
Each table is completely independent of any other tables and all records in a
given table have the same number of fields.
C.4 Default Tables
Each table-based datalogger has a set of default tables plus the tables created
by the datalogger program. The four default tables in the CR10X-TD family of
dataloggers, are Timeset, Errorlog, Inlocs, and Status. The default tables in
CR5000, CR1000, CR3000, CR800, CR9000, and CR200 dataloggers are
Status and Public.
•
Timeset Table – The Timeset table contains a history of clock sets for the
datalogger. It includes three fields: TimeStamp, RecordNumber, and
OldTime. TimeStamp is the time and date the clock was set.
RecordNumber is incremented each time the clock is set. When the
datalogger is reset or a new program is loaded, RecordNumber is reset to 1.
OldTime is the datalogger’s clock value before the time was set (CR10X-
TD family dataloggers only).
•
Errorlog Table – The Errorlog table contains any errors that occur in the
datalogger. It includes three fields: TimeStamp, RecordNumber, and
ErrorCode. TimeStamp is the time and date the error occurred.
RecordNumber is incremented each time an error occurs. When the
datalogger is reset or a new program is loaded, RecordNumber is reset to 1.
ErrorCode is the code returned by the datalogger when an error occurs.
Refer to the datalogger user’s manual for a list of all error codes (CR10X-
TD family dataloggers only).
•
Inlocs Table (CR10X-TD family dataloggers) or Public Table (CR-x000
dataloggers) ─ When a datalogger measures a sensor, the sensor reading is
stored in a temporary register called an input location or variable. With
each new measurement, the old value is overwritten by the new value.
The Inlocs or Public table contains a time stamp, record number, flag
C-6