9
A good indication as to whether the stray light level is within specification may be obtained as
follows:
1.
Set the wavelength to 340 nm.
2.
Set the
MODE
button to
T
.
3.
With the square cuvette adapter in the Sample Compartment without a cuvette close
the lid and press the
0A/100%T
(
∧
) button to set the display to 100.0%.
4.
Remove the cuvette adapter from the Sample Compartment and close the lid. Make a
note of the reading that should be at or near 0.00.
5.
Prepare a solution containing 50 mg/L of sodium nitrite (NaNO
2
) in distilled water and
fill a square cuvette with this solution.
6.
Insert the cuvette into the cuvette adapter, place it in the Sample Compartment, and
close the lid. The display should read < 0.5%T. If the reading obtained in
step
4
is
greater than 0.00, it should be subtracted from the displayed reading to give the correct
reading for the stray light value.
Troubleshooting
PROBLEM
Possible Cause
Solution
Instrument
Inoperative
(Power indicator
has no light)
Power cord not connected to outlet
Plug instrument in.
Dead Power outlet.
Wrong voltage setting.
Change to a different outlet.
Internal fuse blown or defective electronic
component.
Call an authorized service
engineer.
Instrument can
not set 100%T
(0.000A)
No Cuvette Adapter in the Sample
Compartment.
Cuvette Adapter must be in
Sample Compartment to
open sample holder shutter.
Light beam blocked:
•
Holder misaligned
•
Shutter
Check sample holder.
Lamp is old or defective.
Replace lamp/bulb.
Lamp is off alignment.
Refer to lamp Replacement
instructions in this manual.
Defective electronic component.
Call an authorized service
engineer.
%T can not be set
to 00.0%T
Sample holder.
Remove Cuvette Adapter or
test tube.
Sample holder shutter.
May be stuck open, close
shutter.
Defective electronic component.
Call an authorized service
engineer.
Incorrect
Bubbles or particles in solution.
Check sample preparation
