Supplementary Documentation
Page 31 of 44
IFC090, IFC090 i with FF
IFC090-FF Configuration
IFC090 FF 01/2005
KROHNE Messtechnik GmbH & Co. KG · Ludwig-Krohne-Str. 5
D-47058 Duisburg
Tel.: 0203-301 309
Fax: 0203-301389 · E-mail: [email protected]
Analog Input block MODE_BLK
Description
Automatic (AUTO)
The Analog Input block performs its functional computations in
accordance to its configuration automatically. Measurement
deliverance and alarm handling are active
Manual
(Man)
The block doesn’t perform an automatic deliverance of valid
measurement values, but freezes the measurement processing to
the last value obtained in Automatic mode. The OUT status limit
switches to ‘Constant’. In this mode it is possible to write to the OUT
value an arbitrary value to test blocks that use this OUT value as
input.
The alarm model works in the same way as in Automatic mode.
Out of Service (OOS)
The block stops its operation and freezes its measurement value to
the last one obtained in Automatic mode. The OUT status switches
to BAD:OutOfService:NonSpecific.
5.3.1
Process Value Selection
By selecting the channel of the Transducer Block, the operator determines which value should be used as
Analog Input block input value. The value received over this channel is the base of the measurement value
processing.
Since the Transducer Block of the IFC090-FF consists of one channel only, the Analog Input block parameter
CHANNEL must be set to ‘1’ to configure the Analog Input block for processing the IFC090-FF flow value.
If parameter CHANNEL is set to a different value than 1, the Analog Input parameter will display a
‘BlockConfigurationError’ in parameter BLOCK_ERR. The block isn’t able to set the actual mode to Automatic.
5.3.2
Linearization and Scaling
The Transducer Block delivers the IFC090-FF measurement value in units of m3/s statically. If this is the unit
that should be passed to the control system, no linearization is necessary and hence parameter L_TYPE has to
be set to ‘Direct’. Otherwise, the parameter has to be set with respect to the following kinds of scaling:
Direct
No linearization. The channel value obtained from the Transducer is used as it came in m3/s.
This presumes that XD_SCALE equals to OUT_SCALE, otherwise a ‘Block Configuration Error’ will be
displayed in BLOCK_ERR.
Indirect
Linear conversion. The channel value obtained from the Transducer will be mapped from the input scaling
(XD_SCALE) to the output scaling (OUT_SCALE).
Example
:
Assumptions:
•
Transducer Block delivers channel value in unit m3/s
•
Analog Input Block should deliver values in unit liter/s
•
1 m3 = 1000 liter
