Instrument Status
Original instructions
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Diagnosing HART Field Instrument Operations
Use the Instrument Status dialog while operating online to monitor the operation of HART field instruments connected to channels of the HART analog I/O module.
This dialog lists connected HART field instruments, and displays variable values for field instruments that are included in the scan. Scans are performed, and the dialog display refreshed, on 1 second intervals.
Place a check mark in the Scan column to include that instrument in the scan. Remove the check mark from the Scan column to remove that instrument from the scan.
Parameters
The Instrument Status dialog includes an upper table that lists the HART field instruments connected to a module channel, and a lower table that displays variable values for each scanned instrument. The parameters displayed vary depending on the Scan Command value selected in the Multiplexer Status page.
The channel-related parameters can include:
Parameter
Description
Channel
The channel number of the HART analog I/O module.
Manufacturer
The manufacturer of the HART field instrument.
Device Type ID
A hexadecimal value indicating the HART field instrument type.
Unique ID
The serial number of the HART field instrument.
Communication Status
The status of the HART field instrument communications, which can be:
  • Buffer overflow – the message size exceeded the receive buffer of the instrument.
  • Longitudinal parity mismatch – the longitudinal parity calculated by the instrument does not match the Check Byte at the end of the message.
  • Framing error detected – The Stop Bit of one or more bytes received by the instrument was not detected by the UART (for example, a mark or a 1 was detected when a stop bit was expected).
  • Overrun error detected – at lease 1 byte of date in the receive buffer was overwritten before it was read.
  • Vertical parity error detected – the parity of one or more of the bytes received by the instrument was odd.
  • Multi-Error detected with code displayed.
Device Status
The status of the HART field instrument:
  • Primary variable out of limits – the primary variable is beyond its operating limit.
  • Non-primary variable out of limits – an instrument variable not mapped to the PV is beyond its operating limit.
  • Loop current saturated – loop current has reached its upper (or lower) endpoint limit and cannot increase (or decrease) any further.
  • Loop current fixed – the loop current is being held at a fixed value and is not responding to process variations.
  • More status available – additional status information is available via command 48 (read additional status information).
  • Cold start – a power interruption or reset has occurred.
  • Configuration changed – an operation was performed that changed the instrument configuration.
  • Instrument not operational
Tries
The number of times the multiplexer attempted to connect to the field instrument.
Failures
The number of times the multiplexer did not receive a response from the field instrument.
Communication State
The scan status of HART field instruments::
  • Searching – The scanner is searching for the HART instrument.
  • Disappeared – There is no reply from the HART instrument.
  • Appeared – The HART instrument sends a reply. The device information in the response matches the original device information.
  • Mismatched – The device information in the reply from the connected instrument does not match the original device information.
Scan
Select this to display dynamic values in the table below.
The variable-related parameters can include:
Parameter
Description
PV1
The primary variable value.
SV1
The secondary variable value.
TV1
The tertiary variable value.
QV1
The quarternary variable value.
PV Loop Current
The primary variable loop current in mA.
PV Percent of Range
The primary variable value as a percent of the value range.
1. The content of each variable is instrument-specific, as determined by the manufacturer.
Click Reset to set to 0 the counting statistics of the channel-related parameters, and to update the Device Status value of each connected HART field instrument.