GF PORTAFLOW 330, Инструкция по эксплуатации

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Operating Procedures Instruction manual
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7.4.2 Changing a site name
To change a site name use the same method described above for generating a new site: but in
this case access a current site name to change rather than an EmptySite. If you change a site
name while the site is logging the logging will stop.
7.5 Instrument Calibration
The Portaflow is fully calibrated before it leaves the factory; however the following
adjustments are provided to allow you to further ‘fine tune’ your instrument to suit local
conditions and application where necessary. Apart from the zero flow offset adjustment, these
are normally carried out only where the instrument is to be used in a permanent or semi-
permanent location.
7.5.1 Adjusting the zero cut-off
This adjustment allows you to set a minimum flow rate (m/s) below which the instrument will
indicate ‘0’. The default setting is 0.1 m/s but you may adjust this value if required.
1. With the instrument operating in FLOW
READING mode, press the Options key to
access the FLOW READING OPTIONS menu
shown.
2. Select Zero Cutoff (m/s) and press the ENTER
key.
3. Enter the value for the Zero Cutoff (e.g. 0.06
m/s) then press the ENTER key.
4. Scroll down to select Exit and press the
ENTER key to return to the FLOW READING
screen.
7.5.2 Adjusting the set zero flow offset
The Portaflow instrument operates by comparing the time taken to send an ultrasonic signal
between two transducers in either direction. A Set zero flow offset adjustment is provided to
compensate for any inherent differences between the two sensors, noise pick-up, internal
pipe conditions etc. It can be used to ‘zero’ the flow indication under no-flow conditions.
If you have adjusted the Zero Cutoff point to anywhere above ‘0’ you must reset it to ‘0’ before
you can observe and adjust the Set zero flow offset, as its value is very small. Once the Set
zero flow offset has been calibrated you can then reapply the Zero Cutoff if required.
1. Stop the liquid flow.
2. With the instrument in FLOW READING mode press the Velocity function key and
observe the reading (m/s). Any reading other than 0.000 indicates an offset error and in
practice this will typically be in the range ±0.005m/s (possibly higher on smaller
diameter pipes). If a greater figure is shown it is worth calibrating the offset to obtain a
more accurate result. Continue as follows:
NOTICE