GF PORTAFLOW 330, Инструкция по эксплуатации

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Instrction manual Operating Procedures
27
3. Press the Options key to access the FLOW
READING OPTION screen shown.
4. Select Set zero flow (m/s) and press the
ENTER key.
5. Press the ENTER key on the subsequent
screen to accept the change, which will return
you to the screen shown.
6. Scroll down to select Exit and press the
ENTER key to return to the FLOW READING
screen.ENTER key to return to the FLOW
READING screen.
In order to cancel any applied offset you must either read flow via Quick Start or switch the
Portaflow instrument OFF & ON. Any value that you trim-out using the offset adjustment will
be added/subtracted from the flow reading across the whole range.
7.5.3 Adjusting the calibration factor
USE THIS FACILITY WITH CARE & ONLY WHERE NECESSARY
The Portaflow instrument is fully calibrated before leaving the factory and under normal
circumstances does not require further calibration when used on site.
This facility can be used to correct the flow indication where unavoidable errors occur due to
the lack of a straight pipe or where the sensors are forced to be fitted close to the pipe-end,
valve, junction etc.
Any adjustment must be made using a reference flowmeter fitted in the system.
With the system running:
1. Stop (Stall) the Portaflow’s totaliser facility and zero it.
2. Run the Portaflow’s totaliser to measure the total flow over a 30-60 minute period, and
note the total flow indicated by the reference flow meter over the same period.
3. Calculate the % error between the Portaflow and reference meters. If the error is
greater than ±1% calibrate the Portaflow as detailed below.
4. Press the Options key to access the FLOW
READING OPTION screen shown.
5. Scroll down and select Calibration factor.
6. Change the calibration factor according to the
error calculated in step 3. For example, if the
Portaflow was reading 1% high then increase
the Calibration factor value by 0.010.
Conversely, if the reading is 1% low then
NOTICE
CAUTION