SMAR LD292, Руководство по эксплуатации, техническому обслуживанию и инструкциям

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Introduction
III
INTRODUCTION
The LD292 is from the first generation of Fieldbus Devices. It is an economical alternative gauge
pressure transmitter. It is based on a field-proven capacitive sensor that provides reliable operation
and high performance. This lightweight design eliminates the need for mounting brackets and
transmitter supports in many applications. It’s microprocessor-based electronics allows total
interchangeability with Smar capacitive sensors. It is automatically corrects sensors characteristics
changes caused by temperature fluctuations. The digital technology used in the LD292 enables the
choice of several types of transfer functions, an easy interface between the field and the control
room and several interesting features that considerably reduce the installation, operation and
maintenance costs.
The
LD292
is part of Smar's complete 302 line of Fieldbus devices.
Some of the advantages of bi-directional digital communications are known from existing smart
transmitter protocols: Higher accuracy, multi-variable access, remote configuration and diagnostics,
and multi-dropping of several devices on a single pair of wires.
Using Fieldbus technology, with its capability to interconnect several devices, very large control
schemes can be constructed. In order too be user friendly the function block concept was
introduced.
The LD292 , like the rest of the 302 family, has some Function Blocks built in, like analog Input, PID
controller, Input selector and Display Block.
The need for implementation of Fieldbus in small as well as large systems was considered when
developing the entire 302 line of Fieldbus devices. They have the common features of being able to
act as a master on the network and be configured locally using a magnetic tool, eliminating the need
for a configurator or console in many basic applications.
The LD292 is available as a product on its own, but also replaces the circuit board for the LD291.
They use the same sensor board. Refer to the maintenance section of this manual for instructions
on upgrading. The LD292 uses the same hardware and housing for the LD291.The LD292 is part of
SMAR's
Series 302
of Fieldbus devices.
The LD292 , like its predecessor LD291, has many built-in blocks, eliminating the need for a
separate control device. The communication requirement is considerably reduced, and that means
less dead-time and tighter control is achieved, not to mention the reduction in cost. They allow
flexibility in control strategy implementation.
Get the best results of the LD292 by carefully reading these instructions.