705-5100-121 Datasheet, PDF (20/56 Pages) Magnetrol International, Inc. – GuidedWave Radar Level Transmitter

4.0 Function Blocks
4.1 Overview
The Enhanced Eclipse Model 705 Guided Wave Radar
Level Transmitter operates on the principle of Time Domain
Reflectometry (TDR). Refer to Bulletins 57-101 and 57-600
for more detailed information on the Eclipse product family.
The Enhanced Eclipse Model 705FF is a Guided Wave Radar
(GWR) level transmitter with seven FOUNDATION fieldbus^™
Function Blocks (one Resource Block, one Transducer
Block, four Analog Input Blocks, and one PID Block). The
idea of Function Blocks, which a user can customize for a
particular application, is a key concept of Fieldbus topology.
Function Blocks consist of an algorithm, inputs and out-
puts, and a user-defined name.
The TRANSDUCER block output is available to the net-
work through the ANALOG INPUT blocks.
• The ANALOG INPUT blocks (AI) take the TRANSDUCER
block level or volume values and makes them available as an
analog value to other function blocks. The AI blocks have
scaling conversion, filtering, and alarm functions.
4.1.1 Universal Fieldbus Block Parameters
The following are general descriptions of the parameters
common to all blocks. Additional information for a given
parameter is described later in that specific block section.
ST_REV (static data revision): a read only parameter that
gives the revision level of the static data associated with the
block. This parameter will be incremented each time a static
parameter attribute value is written and is a vehicle for
tracking changes in static parameter attributes.
TAG_DESC (tag descriptor): a user assigned parameter
that describes the intended application of any given block.
STRATEGY: a user assigned parameter that identifies
groupings of blocks associated with a given network connec-
tion or control scheme.
ALERT_KEY: a user assigned parameter which may be used
in sorting alarms or events generated by a block.
MODE_BLK: a structured parameter composed of the
actual mode, the target mode, the permitted mode(s), and
the normal mode of operation of a block.
• The actual mode is set by the block during its execution to
reflect the mode used during execution.
• The target mode may be set and monitored through the
mode parameter.
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57-640 Eclipse Guided Wave Radar Transmitter - FOUNDATION fieldbus^™