6.11 Calibration of the rate display using
internal reference: ‘5Et’
Using the ‘5Et’ function the rate display can be
calibrated without the need to know the value of
the 4/20mA input current, or to disconnect the
BA358E Rate Totaliser from the 4/20mA loop.
When using the ‘5Et’ function the instrument’s
internal reference is used to simulate a 4mA and
20mA input current.
Zero
rate display with a simulated 4mA input
Span
rate display with a simulated 20mA input
To calibrate the rate display select '5Et' from the
configuration menu and press
P
.
The Rate
Totaliser will display 'ZEro', pressing
P
again will
reveal the current rate display at 4mA. The
flashing digit can be adjusted by pressing the ▲ or
▼ buttons, when set as required pressing
P
will
transfer control to the next digit. When all the
digits have been adjusted, press
E
to return to the
'ZEro' prompt.
To adjust the rate display at 20mA, press the ▲
button which will cause the Rate Totaliser to
display '5PAn', pressing
P
will then reveal the
existing rate display at 20mA. The flashing digit
can be adjusted by pressing the ▲ or ▼ buttons,
when set as required pressing
P
will transfer
control to the next digit. When all the digits have
been adjusted press
E
twice
t
o return to the '5PAn'
prompt followed and then to the ‘5Et’ prompt in the
configuration menu.
6.12 Clear grand total: ‘Clr.Gtot’
The grand total is a separate sixteen digit counter
which duplicates the total display but is not zeroed
when the total display is reset to zero. The grand
total may be viewed in the operating mode in two
eight digit sections as described in section 2.1 of
this manual. The following table illustrates how
grand totals are displayed.
Grand total High display Low display
1234567890123456
12345678
90123456
-1234
-1234
-12345678
-
12345678
-1234567890
-12
32567890
-123456789012345
-1234567
89012345
The grand total counter can be reset to zero from
the 'CLr.Gtot' function in the configuration menu, or
from the operating mode if the local grand total
reset has been activated, see section 6.17.
To zero the grand total from within the
configuration menu select 'Clr.Gtot' and press
P
which will cause the instrument to display 'Clr.no'.
Press the ▼ or ▲ button until 'CLr.YES' is
displayed and then press
P
which will result in a
'0000' prompt. Using the ▼ and
▲
buttons and
the
P
button to move to the next digit, enter '5urE'
digit by digit to confirm the instruction. Pressing
E
will then reset the grand total counter to zero,
briefly displaying ‘Gt CLrd’ to confirm that the
instruction has been performed and return the
instrument to the 'CLr.Gtot' prompt in the
configuration menu.
CAUTION
After resetting the original grand
total can not be recovered.
6.13 Timebase: t-bA5E
Together with the total scale factor '5CALE-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 BA358E rate display
represents flow per second, per minute or per
hour. See Fig 6.
To check or change the timebase select 't-bA5E'
from the configuration menu and press
P
which will
reveal the current setting. Pressing the ▼ or ▲
button will index though the following three options.
BA358E
Rate display
Represents
flow
Select
in
t-bA5E
menu
Total display
= rate display
divided by
Per second
‘tb – 1’
1
Per minute
‘tb – 60’
60
Per hour
‘tb – 3600’
3600
After selecting the required divisor, press
E
to
return to the ‘t-bA5E’ prompt in the configuration
menu.
6.14 Function of the
P
push-button: ‘C - - P’
When the Rate Totaliser is in the operating mode,
operating the
P
push button will display the input
current in milliamps, or the displayed flow rate as a
percentage of the difference between the displayed
flow rate at 4mA and 20mA inputs.
To check or change the function of the
P
push
button select 'C - -P' from the configuration menu
and press
P
to reveal the current setting. Pressing
the ▲ or ▼ button will toggle the setting between
'4-20' the current display in milliamps and 'PC' the
percentage display. When set as required press
E
to return to the ‘C - - P’ prompt in the
configuration menu.
Note:
The percentage option ‘PC’ is not available
when the sixteen segment lineariser is selected
see section 6.4.
18
