Schambeck SFD GmbH
Refractive Index Detector RI2012
RI2012 V1.0 06-2013.EN / 28.10.2013
50
http://www.schambeck-sfd.com
16.2.3
E
RROR
M
ESSAGE
“S
IGNAL
#
TOO LOW
”
OR
“S
IGNAL
#
TOO LOW
”
The intensity alarm message can show up directly after initialization of the instrument
or during operation. There are two different ways of displaying this message.
It is normal that you get no beep from the RI2012 refractive index detector when you
press the
AutoZero
or
PURGE
button while the
“
S
IGNAL
#
TOO
LOW
”
or
“
S
IGNAL
#
TOO LOW
”
message is shown. In this case it makes no sense to press the
AutoZero
or
Polarity
buttons when there is no signal value shown in the display. The
functions
AutoZero
and
Polarity
are only active if there is a detector signal.
Is the message
“
S
IGNAL
#
too low
”
displayed, the voltage U
Summ
is below 1.7 V.
The reason is low light intensity reaching the light sensor.
To resolve this problem, try the following: Purge the reference chamber and the sample
chamber of the flow cell and make sure that both chambers are filled with mobile phase
Check the light source (
see chapter 16.4
Make sure the flow cell is clean (
see chapter 16.7
)
Adjust the alignment of the optical system (
see chapter 16.3
Check the lamp current, it might be too low. (
see chapter 16.4 and page 58
)
In case of the message
“
S
IGNAL
# too hight
”
the problem is that the voltage U
Summ
is
beyond 7.5 V. This might be caused by several facts:
The lamp current is too high, check lamp current
The cover of the optical system is open and light from outside reaches the light
sensor
