AR 10013164, Operating And Service Manual

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FL7006/FL7030/FL7218/FL7040/FL7060Kit
Rev J 11
2.2.5 Optical Transmitter
The probe transmits responses via a low power optical transmitter, or photodiode. The photodiode is off, no
light, when there is no transmission.
2.2.6 Control Logic
Functions within the probe are controlled by an on-board microcontroller. Analog-to-digital (A/D) converters
are used to digitize the levels from the preamplifiers, the photon power converter voltage, and internal
temperature. The microcontroller corrects these values using on-board calibration tables and processes all
communication in and out of the probe.
2.2.7 Sampling
The control program (firmware) controls the collection of 12-bit A/D samples from each input in a rapid
sequence, repeated for 16 samples of each input, and completed in 1200 microseconds. This is sufficiently
short in time that the readings may be considered to have been taken at the
same time. (For best accuracy
users are advised to control the sample timing so as to request data when the field levels are not intentionally
being changed. Untimed changes can typically be resolved by making several measurement samples and
using values only after the readings have stabilized.) Typically, samples are taken only upon receipt of a host
request for measurement. The sampled data is digitally processed to calculate the measured field level. The
firmware applies probe specific factory generated probe calibration data. This data includes temperature
correction data based on the internal probe temperature monitor.
2.3 PROBE INTERFACE
The FI7000 Interface provides power and communication to the probe and houses the laser light source,
control logic, and communication interfaces.
2.3.1 Laser
The laser module provides photon (light) power to the probe. The laser module contains an embedded
Class 4 laser with a peak output of 500mW and a wavelength of 850mm.
2.3.2 Optical Receiver
The optical receiver is a conventional-packaged photodetector.
2.3.3 Power Supply
All circuitry is powered by a 5V DC power supply.
2.3.4 Interfaces (IEEE, RS-232, F/O RS-232, USB)
Refer to specific probe kit specifications interfaces to a host. All interfaces are controlled by the control logic
2.3.5 Control Logic
The control logic provides operational control and routing of signals. It includes a microcontroller. It
functions to route the host commands, received from one specific controller/host interface, forward to the
probe, and to route the probe responses backward to the same controller/host interface. Model-specific
microcontroller firmware controls all aspects of the controller operation.