Solartron Mobrey 7828, Technical Manual

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78285000_AB
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Introduction
1.1 ABOUT THE 7828 DENSITY TRANSMITTER
1.1.1 WHAT IS IT?
The 7828 Density Transmitter is based on Solartron's proven tuning fork technology. It is
an all-welded sensor designed to be mounted directly in-line or into a tank. Density is
determined directly from the resonant frequency of the tuning fork immersed in the fluid,
and a temperature sensor (PRT) is also fitted within the transmitter.
The transmitter contains integral processing electronics to provide full ‘on node’
configuration, enabling it to perform a variety of calculations. Two outputs are available:
1. A direct 4-20mA output giving an output proportional to a user selected process
parameter or calculation result, with configurable span, bias, limits and filter
options:
•
=
line density
•
=
line temperature
•
=
°API
•
=
S.G.
•
=
base density (API)
•
=
base density (Solartron matrix method)
•
=
special calculation result.
2. An RS485(Modbus) interface , giving access to other measurement results,
system information and configuration parameters.
No signal converter is required, which simplifies wiring and enables the 7828 to be
connected directly to a plant monitoring and control systems and/or a local indicator.
The 7828 is factory set to perform either API or Matrix referrals. Re-configuration of the
7828’s default settings (see Appendix A) is achieved by linking a PC to the Modbus
(RS485) connection and running Solartron's ADView software. Once configured, the PC
can be removed.