AR FI7000, Руководство по эксплуатации и обслуживанию

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PL7004 Kit
14 Rev F
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Do not attempt to switch on the laser unless all of the fiber optic cables are attached.
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Do not attempt to switch on the laser if any of the fiber optic cables show signs of damage.
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Remove the key from the key switch when not in operation.
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Never manually force open the shutters on any of the fiber optic connectors. Damage to the connectors
will result and laser radiation may escape.
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Never attempt to look directly or indirectly into the fiber ends. The fibers carry invisible light (sometimes
laser) and serious injury to the eye may result.
3.3 GENERAL GUIDELINES FOR USE OF FIELD PROBES
This section relates to electric field probes in general.
3.3.1 Definitions of Terms as Used in This Manual
Response time for probe (or for probe interface).
Response time is the elapsed time from the end of the transmission of a specific request for data, to
the end of transmission of the appropriate data response to the requesting device.
This time is transmission speed dependent. So this would not include the time to transmit the request,
but would include the time to transmit the response. For a case in which the response is a 240 bit
serial data string at 19,200 bits per second the response time could not be less than 12.5 ms. Response
time will be longer to allow time for probe and interface calculations.
Time to valid reading for probe.
The time beginning after a field has stabilized, to the time at which a measurement of that field would
be available to be read at a value within about 2 % of final value.
This would be about four time constants of the detector/amplifier response, plus the total defined
sampling and A/D conversion and smoothing times. This time is not transmission speed dependent.
[This time is field level dependent in certain AR probes, a longer time at low levels. The shortest time
is in the sub ms range, longest in the 50 ms range, though it may be extended on some models to
improve sensitivity.]
Request time
The time to prepare and transmit the request for data.
Detector Charge Time Constant
Detector charge time constant defines the limit of the response speed of the detected signal. It
generally includes all factors that affect time constant up to the digitizing of the analog signal. This is
usually assumed to be a single pole filter response and as such will have an exponentially changing
level with time. When expressed as a time constant, user must allow at least several multiples of the
time constant –time- to pass before the level to be read has stabilized, in order to produce an accurate
reading with typical processing. A similar limitation occurs when a separate discharge time constant
is specified.
The above definitions are useful for estimating the time after start at which to expect good data. However, a
moderately sophisticated application program could just read the values continuously until receiving five or
more reading which fall within a predefined (statistical) amplitude range, indicating that all processes have
stabilized, before reporting the readings.