BEKA BA334D, Руководство пользователя

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6. PROGRAMMING & CALIBRATION
The BA334D is programmed and calibrated via
four push-buttons which are located behind the
instrument control cover. If frequent access
to the push-buttons is required, the rate
totaliser can be supplied with duplicate
membrane push-buttons mounted on the
outside of the control cover.
All the programming functions are contained in
an easy to use menu that is shown
diagramatically in Fig 9. Each function is
summarised in section 6.3 and includes
references to more detailed information.
Although this simple menu driven system
enables most adjustments to be made without
repeated reference to this manual, it is
recommended that at least the summary of the
programmable functions in section 6.3 is read
before attempting programming or
recalibration.
When the BA334D is fitted with alarms, pulse
output or 4/20mA output, the basic menu is
expanded to include the option(s). Section 9
of this manual explains how to programme
these additional functions.
Note: While the instrument is being
programmed or calibrated, totalisation
continues so that any flow occurring during this
time is recorded.
6.1 Calibration structure
Fig 8 shows the BA334D calibration structure.
The rate and total display calibration functions
are totally independent allowing the displays to
have different engineering units.
For the rate display the pulse input is scaled by
SCALE-r to represent engineering units and
multiplied by the timebase t-bASE to calculate
and display the rate of flow per second, minute
or hour.
Similarly, to calculate the total flow in
engineering units the number of input pulses is
divided by the total scale factor SCALE-t. Total
flow is continuously added to the grand total.
The BA334D displays ‘real’ decimal points.
Moving the position of a decimal point in a
scale factor will therefore affect the instrument
calibration.
The BA334D updates its total flow calculation
twice per second. If the instrument is used for
batching applications, this resolution may
define the accuracy of the system.
Note: The total and rate displays may be
updated less frequently depending upon the
display update time selected.
Fig 8 Calibration structure
6.2 Accessing programming functions
Throughout this manual push-buttons are
shown in italics e.g. P or Up push-button, and
legends displayed by the instrument are shown
within inverted commas e.g. 'CAL' and ' ALr2'.
Access to the programme menu is obtained by
operating the P and E push-buttons
simultaneously. If the instrument is not
protected by a security code the first parameter
'UPdAtE' will be displayed. If a security code
other than the default code 0000 has already
been entered, the instrument will display
'COdE'. Press P to clear this prompt and enter
the security code for the instrument using the
Up or Down push-buttons to adjust each digit,
and the P push-button to move control to the
next digit. If the correct code has been
entered pressing E will cause the first
parameter 'UPdAtE' to be displayed. If an
incorrect code is entered, or a push-button is
not operated within ten seconds, the
instrument will automatically return to the
display mode.
Apart from defining the position of the decimal
point in the rate display all programme
functions and prompts are shown on the large
eight digit display.
Once within the main programme menu the
required parameter can be reached by scrolling
through the menu using the Up and Down
push-buttons as shown by the programme
structure in Fig 9.