KROHNE UFC 500 HART User Manual

Page 14

HARTô Smart Communications Protocol

UFC500 Command Specification Rev: 2.0 Release Date: 9 Jun 2001

Page

If Transmitter Variable Code equals to м0о, flowrate units are changed (refer to Command #44). If Transmitter Variable
Code corresponds to any totalizer (refer to section 5.1), the requested unit will affect all of them. The list of valid for
this transmitter totalizersí unit codes is placed into Table 9.2.

Note that for totalizer measurements transmitter supports all the HCF units for volume except the ones for gaseous
media. The device display can make use only of some small subset of corresponding HCF/transmitter units. The impact
of these on the instrument remote/direct control is detailed in section 7.4, ìWrite Primary Variable Unitsî.

7.8

Command #60

Read Analog Output And Percent Of Range

If the requested output currently deals with Direction or Off variable, the Percent of Range value is replied as Not-a-
Number.

The output value for the pulse output is responded either in manufacturer specific units м249о, ìpulses per secondî - for
FlowRate or TransitTime variables, or in ìVoltsî (58) - for Direction or Off variables.

7.9

Command #66

Enter/Exit Fixed Analog Output Mode

If this command is used to deal with current output, then Analog Output Number Code must be set to м1о and Analog
Output Units - to м39о, mA. The instrument will accept any IEEE value in the range 0.0 to 22.0 as a desirable fixed
current level.

While testing pulse output, set Analog Output Number Code to м2о and Analog Output Units - to м249о, ìpulses per
secondî. The instrument will accept any IEEE value in the range 0.0 to 10000.0 as a desirable fixed output level.

Without external stimulus the instrument will leave HART-activated fixed output mode in 2 minutes.