Multiplexer Status

Multiplexer Scanning

Use the Multiplexer Status dialog to:

perform the following offline configuration tasks:
- enable and disable scanning by the multiplexer of HART field instruments
- specify a Scan Mode
- set maximum limits for both Communication Count and Busy Retry Count
monitor statistical data describing the operation of the HART multiplexer
diagnose the multiplexer status using status LEDs

HART Port Parameters

The following HART port parameters can be accessed in the Multiplexer Status dialog:

Parameter	Description
Scan Command	Specify a scan command: Read PV Read Current (mA) and % of Range Read Current (mA), PV, SV, TV and QV
Scanning	Specify a scan mode: ON: enable scan OFF: disable scan
Communication Retry Count	Type in the number of times the HART interface module resends a command to a non-responsive HART instrument. Valid values = 0...5. Default = 0.
Busy Retry Count	Type in the number of times the HART module resends a command after receiving a busy reply from a HART instrument. Valid values = 0...5. Default = 0.
Gender	The type of master: Primary (default) Secondary
Search Algorithm	Type of search performed for instruments on the loop: Poll Address 0 Only Poll Address 0 to 15 (default) Poll Address 0 to 63
Max Instruments Connected	The maximum number of instruments that can be connected to the multiplexer.
Instruments on Instrument List	The number of instruments on the instruments list.

Multiplexer Status

The Multiplexer Status dialog indicates the status of the multiplexer as a whole, and monitors the existence or absence of several multiplexer states. The status of each state is indicated by the LED color, as follows:

Red indicates the existence of a detected event of the specified type.
Green indicates normal operations.
Gray indicates the DTM is offline and is not communicating with the device.

The Multiplexer Status dialog displays the following multiplexer status states:

State	Description
Device Malfunction	A detected error rendered the instrument non-operational.
Configuration Changed	An operation occurred that changed the instrument configuration. NOTE: Click Reset to clear detected faults and update module status.
Cold Start	The instrument was reset, or power was cycled off then on.
More Status Available	Additional instrument information is available via HART command 48 (Read Additional Status Information).