Conf - Change I/O - Ranging Option - ABB 691HT Operating Instructions Manual

CONFIGURATION
CHNG XMTR GEN
I / O I NFO CONF
U N I T S : b a rs
N E X T L A S T CHNG
O P T N O P T N
L R V : 0
U R V : 7 0 . 0
N E X T L A S T CHNG
O P T N O P T N
W A R N I N G - Control l o o p
s h o u l d be i n m a n u a l
L R V : [ 0
U R V : 7 0 . 0
< - - - -> C L R
L R V : 0
U R V : [ 7 0 . 0
< - - - -> C L R
L R V : 0
U R V : 1 4 0 . 0
N E X T L A S T CHNG
O P T N O P T N
W A R N I N G - l o o p m a y be
r e t u r n e d to a u t o
- 22 -

CONF - Change I/O - RANGING option

The operation of Ranging on the Smart Transmitters differs substantially
DBASE
from the same operation performed in the conventional analog transmitters.
MEM
The linearity compensation of the Smart Transmitter allows to select any
value of the LRV and URV within the LRL and URL ( lower and upper
range limits ) with the unique limitation of the minimum span. The
expected accuracy will be in the limits stated in the transmitter specification,
providing that the minimum span limit is not exceeded.
The transmitter being pre-calibrated in factory, the operation of ranging
can be done without the use of external testing equipment: this peculiarity
allows the modification of the range even with the instrument installed
in the field and in operation. To perform the ranging operation proceed as
follows.
Pressing, from the previous display, the F1 key ( NEXT OPTioN ), the
following display appears ( the values shown are just examples ).
Pressing the F3 key it is possible to change one or both the values: the
change of the value will cause a sudden change in the transmitter output
and then precautions must be taken to avoid disturbance to the relevant
P R O
process. A WARNING is then displayed to remember to switch to manual
C E E D
the associated control loop. This message is not repeated when more
configuration operations are performed without exiting from the
configuration procedure.
]
Pressing F4 ( PROCEED ) the new display appears: the LRV value is
displayed within square brackets and a blinking cursor will be positioned
E N T R
on the most significant digit. Using the numeric keypad digit the required
new value: the cursor automatically shifts right. In case of error it is
possible to clear the whole value, using the CLR key, or to clear any digit
]
moving the cursor using the F1 or F2 key and overdigiting the correct
value. In case that no changes are required or to enter the new value
E N T R
press the F4 key ( ENTeR ) : the display changes to the following.
Proceed in the same way to make changes to the URV and confirm the
change with the F4 key. If the ESCAPE is used to return to the CONF
initial display a WARNING message is displayed to remind to change the
loop to Auto.
In case that during the range option operation the LRL or the URL ( lower
and upper range limits ) or the span limit are exceeded, the modification
does not take place and the following warning message is displayed:
" COMMAND#35 Response Code: 10 ( or 11 or 14 ). Press any key to
P R O
continue ". See the messages section for full details.
C E E D