GF PORTAFLOW 330, Инструкция по эксплуатации

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Troubleshooting Instruction manual
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paperclip into the pinhole located in the right-hand side of the instrument to operate the
internal reset switch. Hold the paperclip perpendicular to the instrument while doing this.
9.6 Diagnostics Display
This feature is designed for advanced users and is intended to provide information that will
aid the user to diagnose problems – e.g. no signal strength. When operating in the FLOW
READING mode you can access a diagnostics screen by pressing the Options function key and
then selecting Diagnostics from the FLOW READING OPTIONS screen. This will display the
operating values for the following parameters.
Calculated time (
μ
s)
This is a value the instrument predicts will be the time in
μ
secs that it should take for the
acoustic wave to propagate across a particular pipe size. This value is ascertained from the
data entered by the user. i.e. Pipe size, material, sensor set etc.
Actual time (
μ
s)
This is the value the instrument measures as the time taken for the acoustic wave to
propagate across the pipe. It is used to see if the signal is being taken from the burst, at the
correct time to get the strongest signal. This value is normally a few
μ
s below the calculated
μ
s value. If, however, this value is much greater than the calculated time then there is a
problem with the set-up.
Flow (m/s)
This displays flow velocity in m/sec to 3 decimal places.
Signal strength
This is the averaged value of Signal and should be a value between 800 and 1600 – where 800
is approximately 50%, and 1600 is approximately 100%.
Gain
Gain values are typically in the range 600 to 850.
Switches
Typical Switches values are None and *10. On small pipes (and when using the test block) the
value should be None. A Switch value of *100 indicates poor sensor set-up or poor
connections.
UP/DN time difference
The difference in transit times between the upstream and downstream signals due to the fluid
flow.
Fluid propagation rate
This is the sound speed of the fluid calculated using the data entered by the user.
Sensor separation
The same value as displayed in the setup screen.