10
instrument will display 'COdE'. Press P to
clear this prompt and enter the security code
for the instrument using the Up or Down
push-button 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
'root' to be displayed. If an incorrect code is
entered, or a push-button is not operated,
the instrument will timeout after ten seconds
and 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 Figs 7A and 7B.
When returning to the operating mode
following recalibration or changes to any
parameters, the total display will show
circulating decimal points for a few seconds
while the new information is stored in
permanent memory.
All new BA358C rate totalisers are supplied
calibrated as requested at the time of
ordering. If calibration information is not
supplied, the BA358C will be set to display a
rate of 0.00 with 4mA input and 100.00 with
20mA input. The total scale factor will be set
to 1.0000 with a timebase of flow per
second. The instrument can easily be
recalibrated on-site.
6.3 Summary of programmable functions
This section summarises all of the BA358C
programmable functions. When read with
Figs 7A and 7B it provides a quick aid for
calibrating the instrument. If more detail is
required, each section contains a reference
to a full description of the function.
SUMMARY
Display
Description of function
'root'
Square root extractor
Enables the square root
extractor for linearising the
output from differential
flowmeters.
Percentage CLIP-OFF, below
which the instrument does not
totalise, is automatically set to
5% of rate when the 'root'
function is turned 'On'.
See section 6.4
'rESn'
Display resolution
Selects the resolution of the
least significant digit of the rate
display. May be set to 1, 2, 5 or
10 digits.
See section 6.5
'd.P.' Decimal points
Defines the position of the
decimal point in both the rate
and total displays.
See section 6.6
'CAL' Calibration of rate display
using external current source.
Enables the zero and span of
the rate display to be adjusted
using an external current source
such as a calibrator. Also
enables a complete loop to be
calibrated from primary element
to the indicator display.
When used with an accurate
traceable current source this is
the preferred method of
calibration.
See section 6.7
