8. Power may be applied to the instrument when the installa-
tion is complete and has been checked by the instrument
engineer or safety officer.
3.0
Function Blocks
3.1
Overview
The Enhanced Jupiter Model 2xx is a level transmitter with
four F
OUNDATION
fieldbus
™
Function Blocks (one Resource
Block, one Transducer Block, and two Analog Input blocks.
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 outputs, 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 values and makes them available as an analog
value to other function blocks. The AI blocks have scaling
conversion, filtering, and alarm functions.
3.1.1 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.
9
46-649 Jupiter Magnetostrictive Transmitter - F
OUNDATION
fieldbus™
