I have connected a smart device to DeltaV system.
I want to map Command 48 Response Byte 3 Bit 6 in DeltaV Operator Station.
This bit indicate the failure of a diagnostic test in the device and will alert the operator that there is a failure in the device.
Please advice on how to do the above.
regards
If you enable the device alerts, the operator will see an alarm for the device. www2.emersonprocess.com/.../WP_PlantWeb_Alerts.pdf since command 48 is a standard status command. This assumes device has a DD installed.
If you include the alarm summary from the HART device alert faceplate then the information will display. I'm not sure if there's a way to specifically poll a bit; I suppose you could check the device alert alarm object for it if that is necessary?
In reply to Frank Seipel:
Frank, this will not work if the instrument does not support PlantWeb alerts.
Alternatively, check in books online: Configuration/Modules/Access Intelligent Field Device Diagnostic Data - this works for all smart instruments.
In reply to István Orbán:
The diagnostic calls documented in BOL do not appear to apply to HART based devices. For HART Devices that support cmd 48, DeltaV polls this diagnostic register in order to populate the Plantweb Alerts. To get this, the device manufacturer must submit the DD to Emerson where the device alert conditions are identified and mapped/masked to the Failure, Warning, Advise Alerts. This is provided to users as a kit downloadable from the Emerson website. These are included in the DeltaV system's next release.
With HART enabled on the CHANNEL, the HART Errors can be used to set the PV to a BAD Status. This would show up on the process variable status and associated PV_BAD alarm. All devices have these common HART Errors. You can ignore some or all of these on the Channel configuration.
It is not possible individually evaluate the status of a bit as the Cmd 48 response is not available to the Control Modules. Typically, if the condition renders the device unable to perform, the HART Error bit is set and this sets the PV status to BAD. the Plantweb Alert for the device will identify the specific conditions affecting the device. This information is also available in AMS.
IF PV_BAD is set, setting a second alarm on the specific condition would not be recommended. The Operator can check the device alerts to determine if this condition is present and guide his response. If the device is compromised and PV should be BAD, then you want this on PV_BAD to force downstream blocks to shed to MAN or other appropriate action.
Andre Dicaire