Thermo Scientific 5030i SHARP, Instruction Manual

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System Description
Firmware
Thermo Fisher Scientific Model 5030 i SHARP Instruction Manual 8-5
This PCB assembly is mounted on the floor plate and has three pressure
sensors attached. The pressure board is used to measure the barometric
pressure, differential pressure across the orifice and vacuum under the filter
tap. All tubing attached to the pressure board is numbered in case of the
need to swap out this board.
The external solenoid is used to permit the pump to either exhaust
normally, or to deliver filtered air to the instrument during the
nephelometer zero.
The pump intake T-fitting provides excess air specifically for periods of
nephelometer zeroing.
The processor firmware tasks are organized into four areas:
●
Instrument control
●
Monitoring signals
●
Measurement calculations
●
Output communication
Low-level embedded processors are used to control the various functions on
the boards, such as analog and digital I/O. These processors are controlled
over a serial interface with a single high-level processor that also controls
the front-panel user interface. The low-level processors all run a common
piece of firmware that is bundled with the high-level firmware and loaded
on power-up if a different version is detected.
Each board has a specific address that is used to identify to the firmware
what functions are supported on that board. This address is also used for
the communications between the low-level processors and the high-level
processor.
Every tenth of a second, the frequency counters, analog I/O, and digital
I/O are read and written to by the low-level processors. The counters are
accumulated over the past second and the analog inputs are averaged over
that second. The high-level processor polls the low-level processors once
per second to exchange the measurement and control data.
Pressure Board
External Solenoid
Pump Intake T-
Fitting
Firmware
Instrument Control