Emerson Rosemount 327T, Quick Start Manual

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Note
Drift monitoring is not possible if a sensor fails and sensor backup is active.
Diagnostic cases
The temperature transmitter identifies error scenarios with these diagnostic cases.
For more information on parameters relating to diagnostic cases, see Adjustable
parameters or Drift Monitoring .
Table 1-1: Warnings
Diagnostic number Description
1 The temperature deviation exceeded the drift warning threshold (drW).
2 The temperature of the internal electronics exceeded the limit of 257 °F
(125 °C).
Table 1-2: Alarms
Case number Description
3 The temperature deviation exceeded the drift alarm threshold (drA).
4 One of the two sensor elements failed.
5 The measured temperature value is outside the allowable measuring
range.
6 The supply voltage is outside the operating range.
(1)
(1) For 2-wire operation, no diagnostic message is provided in case of low voltage (see Diagnostic
function (two-wire) ).
Table 1-3: Failures
Case number Description
7 The temperature deviation exceeded the drift failure threshold ( drF ).
8 An error occurred while setting parameters using IO-Link.
9 Both sensor elements failed or general electronics problems.
Diagnostic function (two-wire)
In two-wire operation, the temperature transmitter uses the analog output for
temperature measurement and diagnostics.
drEd configures the diagnostic cases that the temperature transmitter signals using the
analog output:
• ON: Limits the diagnostic messages to only failure messages. The temperature
transmitter will signal only diagnostic cases 7-9.
• ONdr: Limits the diagnostic messages to alarm and failure messages. The temperature
transmitter will signal only diagnostic cases 3-9.
Quick Start Guide Introduction
00825-0100-4329 January 2019
Quick Start Guide 9