Reference Manual
748384-C
September 2003
1-8 Introduction
Rosemount Analytical Inc. A Division of Emerson Process Management
NGA2000 Reference
4. Select
Manufacturing data...
5. Select
Analyzer module data.
6. Edit the minimum and maximum ranges
as desired.
c. Details
The analyzer won't let you edit the fullscale
range to a value higher than the maximum
range, or lower than the minimum range.
Outside these bounds the analyzer won't
meet its specifications, probably. Only edit
these if you have made a hardware change
to the analyzer so that it can now cover a
new range.
If you increase a range by more than 10%
without changing the linearizer range, the
analyzer will disable that linearizer. How-
ever, don't simply increase the linearizer
range to avoid this - the coefficients must be
changed as well, or you will have linearity
errors.
Any bound I/O module will get its ranges
from the analyzer, you don't have to change
them in the I/O module as well.
Network variables: RNGHI, RNGLO,
CRANGE, CURRENTRNGHI, CURREN-
TRNGLO, MAXRANGE, MINMANGE, LIN-
RNGHI, LINA0_, LINA1_, LINA2_, LINA3_,
LINA4_
d. Troubleshooting
I changed a range and now my linearity
is wrong…
You have to change the linearizer parame-
ters if you change a range value. You can't
use a linearizer that covers less than 90%
of the range you axe on. Either select the
linearizer from the next higher range, or
re-linearize the present range.
It won't let me make the range bigger (or
smaller)…
You have reached the editing limits set by
the minimum range or the maximum range.
You probably should not be setting the
ranges outside of these limits. If you have
made a physical change to the analyzer, or
you are willing to live with the lower specifi-
cations, you can edit the minimum or maxi-
mum ranges in the
Manufacturing data
screen.