5.4 Rate Totaliser function: ‘FunC’
This configuration function defines the relationship
between the Rate Totaliser’s 4/20mA input current
and the instruments’s rate display. Three
alternatives are available for uni-direction flow and
two for bi-direction flow.
For uni-directional flow:
‘5td’
Standard
linear
relationship
‘root’
Square root extraction
‘Lin’
16 segment adjustable lineariser
For bi-directional flow:
‘bi-5td’ Standard
linear
relationship
‘bi-Lin’ 16 segment adjustable lineariser
To reveal the existing instrument function select
'FunC' from the configuration menu and press
P
.
If the function is set as required, press
E
to return
to the menu, or press the
▲
or
▼
button to change
the setting, followed by the
E
button to return to the
configuration menu.
‘5td’
Linear
Provides a linear relationship between the
4/20mA Rate Totaliser input current and
the instruments rate display for
uni-directional flow.
‘root’ Square root extraction
Primarily intended to linearise the square
law 4/20mA output from differential
flowmeters.
For reference, the following table shows
the output current from a non-linearised
differential flowmeter.
% of full flow Current output mA
2.5
4.01
10.0
4.16
25.0
5.00
50.0
8.00
75.0
13.00
100.0
20.00
When the root function is selected the Rate
Totaliser will display flow in linear units for
uni-directional flow.
‘Lin’
16 segment adjustable lineariser
May be adjusted to compensate for
flowmeter non-linearity with uni-directional
flow. Use of the lineariser is described in
section 6 of this instruction manual.
‘bi-5td’ Linear
Provides a linear relationship between the
4/20mA Rate Totaliser input current and
the instruments rate display for
bi-directional flow.
‘bi-Lin’ 16 segment adjustable lineariser
May be adjusted to compensate for
flowmeter non-linearity with bi-directional
flow. Use of the lineariser is described in
section 6 of this instruction manual.
5.5 Display resolution: ‘rE5n’
This function defines the resolution of the least
significant display digit of the rate display.
Decreasing the display resolution can improve the
readability of a noisy signal. Select ''rE5n' from
the menu and press
P
which will reveal the current
display resolution. To change the resolution press
the
▲
or
▼
button to select 1, 2, 5 or 10 digits,
followed by the
E
button to enter the selection and
return to the configuration menu.
5.6 Display update time: ‘uPdAtE’
If the rate display is likely to change rapidly,
extending the time between display updates will
make the display easier to read. Five different
intervals between readings are selectable, 1, 2, 3,
4 or 5 seconds.
To reveal the existing update time select 'uPdAtE'
from the configuration menu and press
P
. If the
time is set as required, press
E
to return to the
menu, or press the
▲
or
▼
button to change the
time, followed by the
E
button to return to the
configuration menu.
This function only changes the interval between
successive display updates, it does not change the
instrument accuracy.
5.7 Upper display: ‘di5P-1’
The Rate Totaliser has two numeric displays:
Upper
8 digit 18mm high intended for showing total flow
display range –9999999 to 99999999
Lower
6 digits 12mm high intended for showing flow rate
display range –99999 to 99999
This function interchanges the rate and total
displays when the flow rate is required to be
predominant, resulting in a 5 digit plus sign upper
rate display and a 6 digit lower total display, or 5
digits plus sign when negative.
To reveal the existing upper display function select
'diSP-1' from the configuration menu and press
P
.
If set as required, press
E
to return to the
configuration menu, or press the
▲
or
▼
button to
toggle the function between ‘totAL’ and ‘rAtE’.
When set as required press
E
to enter the
selection and to return to the configuration menu.
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