Watlow D4T Data Logger
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Chapter 5 Function Reference
3. Error Status
• A signal's error status indicates whether or not the value can be relied on. A signal with
no errors (error status is none), is displayed as a black line in Composer. When some-
thing is wrong such that a function block cannot determine an appropriate value to
transmit, the signal is displayed as a yellow line in Composer. You can determine the
specific error status by mousing over the signal in the diagram. The table below lists
the possible errors that could be presented to the user. Any error status other than
none
is considered an error.
Error Status
Description
None
No error is detected.
Open
A sensor is broken or disconnected.
Shorted
A sensor has failed or is shorted.
Measurement Error
A measurement error has occurred.
Bad Calibration
The data logger has not been calibrated.
Ambient Error
The ambient temperature is outside of the data logger's operat-
ing range.
RTD Error
An RTD sensor error has occurred.
Fail
A measurement failure has occurred.
Not Sourced
The source FB is missing a required signal at one of its receiv-
ers.
Stale Data
Data sourced from another data logger has become unavailable.
Math Error
A calculation has no defined result (such as divide by zero).
This chapter describes in detail each of the available functions as well as their associated pa-
rameters.
Note:
The addresses and other information required to read or set FB parameter values via a
field bus protocol is located in the "Communications" section of the Appendix to this Us-
er's Guide.
Alarm
Use an alarm to monitor an analog signal and set an output when that signal goes above or
below the user-set alarm conditions. This block is found in the Function Block Diagram edi-
tor’s Library when working with a data logger that offers the Alarm block. The number of
these blocks available is shown within the parenthesis.
Use the Type parameter to set the block’s behavior. These options for Type are described in
detail in the following sections:
: no alarms occur. The block’s output is off.
: monitors an analog signal for specified alarm conditions.
: monitors an analog signal for alarm conditions relative to another signal.