FTS SDI-PT-KEL, User Manual

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700-SDI-PT-KEL-Man Rev 4 06 Jan 2020 7/19
result in excessive SDI-12 retries, incorrect data, or even no response. SDI-12 commands (like a MC!)
which add a CRC
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can greatly improve incorrect data issues.
The following format is used to specify the different parts of an SDI-12 command and sensor reply.
Mandatory elements are in bold:
Item Meaning Text
representation
Sensor Address First character of a command* and
response. Valid values 0-9, a-z, A-Z. a
Command literal Part of a command that must be
reproduced literally as it appears; X
Command
parameter Part of a command that must be filled in
with an appropriate value. xxx
Optional
parameter Part of a command that can be omitted if
not needed. The brackets [ ] are not
included in the command. [xxx]
Floating point
number Number representing a measurement value
or command parameter. If a command
parameter it will be bolded and may be
marked as optional.
u.uuuuu or
[u.uuuuu]
Replies As above but not bolded u.uuuuu
Command
Terminator The last character of a command !
*
except the address query
3.3 ERROR DISPLAYS
The following error values are displayed for the D and R commands if the continuous measurement
mode is switched on with the corresponding extended command.
Field Value Displayed Meaning
Pressure +9999999
1) Overflow (re10% of the specified range)
2) Pressure element damaged
-9999999 Underflow (readings -10% of the specified range)
Temperature +9999999 Overflow
-9999999 Underflow
nan Damaged or unreadable sensor value +9999999
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Cyclic Redundancy Check – an error detecting code used to detect accidental changes to raw data.