Baker Hughes DigitalFlow XGF868i, Руководство по программированию

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Table 18: Transducer signal settings
Transducer signal
parameters
Range
Default
value
Description
Amplitude
discriminator low
0 to 100 14
The amplitude discriminator measures the transducer signal
received by the model XGF868i. The default value for the above
parameter is 14, and values from 0 to 100 are acceptable. The
E5: AMPLITUDE error message appears when the amplitude
discriminator falls below the programmed AMP. DISCRIM LOW
value. See Chapter 2 in the service manual for a discussion of
error codes.
Amplitude
discriminator high
0 to 100 34
The amplitude discriminator measures the transducer signal
received by the model XGF868i. The default value for the above
parameter is 34, and values from 0 to 100 are acceptable. The
E5: AMPLITUDE error message appears when the amplitude
discriminator exceeds the programmed AMP. DISCRIM HIGH
value. See service manual, Chapter 2 for a discussion of error
codes.
Delta T offset -1000 to 1000 µsec 0 µsec
An offset between the upstream and downstream transit times
is specified at this prompt.
Skan T offset –500 to 500 µsec 58 µsec
At this prompt, specify a time measurement offset that
compensates for any shift resulting from cross-correlation. Set
to 0 for active skan T offset.
% of peak 1 to 100% 50%
The percentage of peak used to calculate the transit times and
Delta T is specified at this prompt.
M>S switch 0 to 250 µsec 50 µsec
If the burst mode is set to skan/measure (S/M), the meter
switches from skan to measure mode when Delta T is less than
the M>S_switch value. DO NOT change this value unless advised
to do so by the factory.
# Shifts 0 to 10 3
The number of shifts corresponds to the actual number of
transmits per cycle (number of signals added together in one
direction to produce an averaged signal for one interrogation of
the fluid) and need only be changed if the environment is very
noisy or the acoustic signal is weak.
A divisor 0.1 to 10 2.5
A divisor is used to calculate the measure mode integrated
threshold level and is not normally changed.
# transmit pulses 1 to 16 4
# transmit pulses specifies the number of pulses in a burst.
For difficult conditions (i.e. long paths, high velocity or high
temperature), settings as high as 16 may be necessary.
T window (cycles) 0 to 1000 0
The XGF868i calculates the size of the transmit window based
on pipe size and fluid sound speed. However, for diagnostic
purposes, the window size may be reset.
R window (cycles) 10 to 128 10
The XGF868i calculates the size of the receive window based
on pipe size and fluid soundspeed. However, for diagnostic
purposes, the window size may be reset.
After responding to the above prompt, the meter returns to the SET UP option window.
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