Bio-Rad Model 550, Ultramark, and Benchmark Microplate Reader Accessories - Manual (Page 32)

Section 6
Troubleshooting and Error Messages
The Model 550 Microplate Reader constantly monitors several vital functions and will dis-
play appropriate messages on the LCD when an error condition is encountered.
1. LCD appears blank on power up.
a. Power switch is not turned on. Turn on the power switch on the rear panel.
b.Unit is not plugged into AC outlet Check power cord connections at outlet and
or power cord is not attached to the on the rear panel of the instrument.
instrument.
c. The AC outlet is non-functional. Check circuit breakers or fuses.
d.Instrument has blown a fuse. Check both fuses on the rear panel of the
instrument, and replace if necessary.
Replace only with the same type fuse. If the
instrument continues to blow fuses,
discontinue use and contact your Bio-Rad
service representative immediately.
2. Instrument displays “Error Light Check whether lamp is emitting light
Bulb” message indicating that the
bulb is burned out.
a. Lamp is not emitting light. Replace lamp as described in Section 5.2.
b. Lamp is emitting light. Check alignment of the lamp in the bezel.
Check the alignment of bulb in the glass
reflector. Align or replace lamp if necessary.
3. Printer will not print on command.
a. Printer paper is not installed properly. Verify that the paper is properly installed.
Refer to Section 3.1 for details.
4. Plate carriage jams during reading, and
“Error Plate Carriage” is displayed.
a. Plate is not seated in carriage properly. Press the STOP button immediately. Position
the plate carefully in the carriage, making
certain that it is properly seated.
5. LCD displays “Error Filter Missing.”
a. A filter is missing from the wheel. Install a filter in the empty position. See
Section 5.1.
b.The filters are not properly seated. Check that all filters are installed properly .
See Section 5.1.
6. Wells have color, but absorbance
values seem low.
a. Incorrect filter used for measurement Check wavelength used in analysis. Read
and/or reference wavelength. plate in single wavelength mode at all wave-
lengths to verify that the proper filter was used.
The measurement wavelength should produce
the highest absorbances. The reference wave-
length produces the lowest absorbances.
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