Emerson NGA2000 Reference Manual page 26

Reference Manual
748384-C
September 2003
The calibration limits are enabled, and the
span drift is greater than that allowed. Dis-
able the limits and try again, or make the
limits wider and try again.
You expect the Autocal module to put a
span gas on the analyzer, but you have
pressed the SPAN button in the Basic con-
trols screen. The Basic controls screen only
controls the analyzer, it doesn't control the
Autocal module. If you press it, you have to
verify the gas is present first! If you want to
use the Autocal module to control the gas
flow, you have to get into the Autocal mod-
ule control screen under Expert controls,
then auxiliary module controls.
One range calibrates, but others don't...
You are probably trying to span all ranges
together when the analyzer cannot do it.
Set the analyzer to span ranges separately,
and span each range on its own span gas.
Alternatively, if you only want to operate on
one range, set all the ranges to the same
fullscale value, then it won't matter which
range you are on and you can span them all
together.
Nothing seems to work, I'm lost...
We have put a back-up, fail-safe into the
design. There are enough settings and
special circumstances that it is quite possi-
ble for both you and the analyzer to get con-
fused, particularly if you have modified the
analyzer hardware or software in some way.
1-12 Introduction
NGA2000 Reference
The first back up is to put the last stored
calibration factors back into the present
ones, by getting into the "Range (n) factors"
screen for the range you are on, and then
getting into the "HISTORY" screen. Press
"RSTR ST" to put the last good factors into
the present set. Alternatively you can re-
store the manufacturing factors with "RSTR
MN".
This won't do you much good perhaps if you
have changed the hardware, since the con-
ditions may be very different now. In this
case, you can get into the factors screen for
the range you are on, and manually edit the
factors on zero gas (edit the zero factor)
and span gas (edit the span factor). Usu-
ally, you can just make the reading ap-
proximately right, and then do a zero or
span using the softkeys in the calibration
screen.
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