GE CTF878, Руководство пользователя и обслуживания

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Diagnostics 1-5
February 2009
Setting Error Limits
The Error Limits option enables you to set limits for the signals
received from the transducers and the limits for some outputs. When
the parameter falls outside the programmed limits, an error indication
appears. To enter this option, scroll to the Error Limits entry on the
Service Menu and press
[ENTER]
. The screen appears similar to
Figure 1-4 below.
Figure 1-4: Signal Error Limits Option
1.
The first prompt asks for the minimum error limit for the
correlation signal-to-noise ratio (SNR) calculated by the CTF878.
The default value is 10. The E8: SNR error message appears if the
SNR falls below the limit programmed here.
IMPORTANT:
SNR
Min
should be changed from factory default
settings only if absolutely necessary. These settings
may be changed by qualified field service engineers,
only.
To enter the minimum SNR:
a.
Press
[ENTER]
to open the text box.
b.
Use the numeric keys to enter the desired value.
c.
Press
[ENTER]
to confirm your entry.
d.
Press the [
X
] or [
T
] key to move to the next limit.
2.
The next prompt calls for the low and high velocity limits. The
E9: VELOCITY RANGE error message appears if the velocity
falls outside these limits. Repeat Step 1 above to enter the desired
limits.
Min Max
OK Cancel
SNR Min
–100 Velocity m/s 100
15 Acceleration m/s
75 Carrier mV 1200
75 DMod mV 1500
Signal Error Limits
10