16
viewed in the operating mode in two eight
digit sections as described in section 2.1 of
this manual.
The grand total counter can only be reset to
zero from the 'CLr.Gtot' function within the
main programme menu. To zero the grand
total counter select 'CLr. Gtot' and press P
which will cause the instrument to display
'Clr. no' with 'no' flashing. Press the Up or
Down button until 'CLr. YES' is displayed
followed by P which will result in a '0000'
prompt. Using the Up and Down buttons
and the P button to move to the next digit,
confirm the request by entering the
password 'SurE'. Note 'S' is entered as '5'.
Pressing E will then reset the grand total
counter to zero and return the instrument to
the 'CLr. Gtot' prompt in the main menu.
WARNING
After resetting the grand total counter
to zero the old grand total can not be
recovered.
6.11 Timebase: t-bASE
Together with the total scale factor 'SCALE-
t', this function defines the arithmetic
relationship between the rate and total
displays. The timebase divides the rate
display by 1, 60 or 3,600 depending upon
whether the BA358C rate display represents
flow per second, per minute or per hour.
See Fig 6.
To check or change the timebase select
't-bASE' from the main menu and press P
which will reveal the current setting.
Pressing the Up or Down buttons will index
though the following three options.
BA358C
Rate
display
represents
flow
Select
In
t-base
menu
Total display
= rate
divided by
Per second
tb – 1
1
Per minute
Tb – 60
60
Per hour
Tb – 3600
3600
Select the required divisor and press E to
return to the main menu.
6.12 Function of the
P
push-button:
C - - P
This parameter defines the function of the P
push-button when the BA358C is in the
display mode. Either the input current in
milliamps or the input as a percentage of
span may be shown.
To check or change this parameter select 'C
- -P' from the main menu and press P to
reveal the current setting. Pressing the Up
or Down button will toggle the instrument
between the two options. Select '4-20' if the
input current in milliamps is required, or 'PC'
if the input as a percentage of span is
required. When the required option is
displayed press E to store the selection and
return to the main menu.
Accuracy of both these options depends
upon the accuracy of the internal references
which should be periodically calibrated - see
section 6.9.2
6.13 Total scale factor: SCALE-t
Together with the timebase 't-bASE', this is a
dividing factor which defines the arithmetic
relationship between the rate and total
displays. The total scale factor may be set
to any value between 0.0001 and 65535*
allowing the total flow and rate of flow to be
displayed in different engineering units.
SCALE-t = Units of rate display
Units of total display
When calculating SCALE-t the required units
of measurement for the total display must be
converted to those used for the rate display
as shown in following example:
The BA358C rate display represents litres
per second but the total flow display is
required in UK gallons. There are 4.5461
litres in a UK gallon.
SCALE-t = Units of rate display
Units of total display
= 1 litre = 1 litre
1 gallon 1/(4.5461) litres
SCALE-t = 4.5461
