KROHNE IFC 010 Converter HART - Manual (Page 12)

HARTÆ Communications Protocol
IFC010 Command Specification Rev: 1.0 Release Date: 29 May 1997
© 1997 KROHNE Mefltechnik D-47058 Duisburg Page 12
TRANSACTION #3
DATA BYTES
#0
PV
VAR
CODE
Changing of Dynamic Variable assignments must obey some restrictions (refer to sections 5.1, 7.10): Primary Variable
Code must be м1о, Secondary Variable Code must be either м0о or м1о,
Tertiary and Fourth Variables will accept any defined Transmitter Variable Code (from м0о to м3о). In the case of any
error request packet will be rejected with response code 2, Invalid Selection.
7.12 Command #53 Write Transmitter Variable Units
If Transmitter Variable Code equals to м0о or м1о, 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.
7.13 Command #62 Read Analog Outputs
Two transactions are supported: bus master can request from 1 to 2 Analog Outputs (with codes м1о for current output
and м2о - for pulse output) in arbitrary set. For pulse output the output value is responded in manufacturer specific units:
м249о, ìpulses per secondî.
7.14 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. For details pertaining to Output Level refer to Command #40.
When Analog Output Units are set to м57о (%) and any allowed Analog Output Number Code is selected, then a joint
test of both outputs is carried out (Menu 2.1, Test Q). Itís very important that unlike Command #40, under this test the
outputs behave as required by their functions, i.e. exactly as they will do in normal operating mode under the same
circumstances. Say, if FlowDirection (Menu 3.2.6; Command #146, Read Primary Constant and Flow Direction) is set
to ì- Dirî (logical positive direction) and the function of current output is set to 1 Dir (Menu 1.5.1; Command #138,
Read Analog Output Function), then for
flow =
±
PV Upper Range Value
the output will be set to 20 mA value for м+о measurements and to 4 mA - for ìnegativeî.
The Output Level defines a test value, in % of Primary Variable Upper Range Value, IEEE 754. Any value is accepted
within the range -110%..+110%. If test value is out of this range, it is set to appropriate boundary; then responded value
will reflect this.
As required, a request with NaN test level exits test mode.
NOTE: While exiting test mode, the Analog Output Units must be specified.
7.15 Command #67 Trim Analog Output Zero
Command can be used for calibration of the current output (Analog Output Number Code = 1). Refer to section 7.7.
7.16 Command #68 Trim Analog Output Gain
Command can be used for calibration of the current output (Analog Output Number Code = 1). Refer to section 7.8.