Advanced Instruments Osmometer 3250 Service Manual

45
Troubleshooting Table Troubleshooting
Symptom Explanation Suggested Action
24. Keypad keys
unresponsive
Connections to the keypad may have
become disconnected, or the keypad
has failed.
1. Check circuit connections to
the keypad (refer to system
schematic).
2. Replace the keypad.
25. Low Battery The lithium battery contained
inside the NVRAM memory is too
low to maintain stored information,
calibration, and system settings. The
instrument will function normally as
long as the main power remains on.
Contact Advanced Instruments for
Hot-Line Service.
26. Low Fluid Level in
Freezing Chamber
The heat transfer fluid pump may
be malfunctioning, or there may be
a leak or obstruction in the fluid
system.
An insufficient amount of fluid is
being pumped with each head up/
down cycle.
3. Evaluate the functioning of the
heat transfer fluid pump per
the instructions found in the
Maintenance section.
4. If an obstruction is suspected,
refer to Osmometer/Cryoscope
Well Cleaning, located in the
Maintenance section.
27. Memory Allocation
Error
Internal memory management error,
allocated reserved memory conflict.
1. Turn power off, then on.
2. If problem persists, replace the
processor board.
28. “New Software
Version”
EPROM has been changed, or new
software has been downloaded.
1. Check system settings and
proceed.
2. If problem persists, replace
processor board.
29. “No Parameters in
RAM” “Parameter RAM
Failed”
The battery-backed RAM has lost its
data or has been cleared.
The instrument has lost the
calibration, data, and probe bin
numbers from memory.
This may occur during some
software updates.
1. Reset sample and block probe
bin numbers. Recalibrate the
instrument.
2. Reset the stir amplitude.
3. Reset the buzz point (3250 only).
4. Reset plateau mode/range.
5. Reset instrument serial number.
6. Reset any other custom settings
7. If problem persists, replace
processor board.
30. “No Plateau, Repeat
Test ”
The sample did not reach a valid
plateau.
1. Make sure the sample is not too
viscous.
2. Check the sample probe.
3. Make sure there is heat transfer
fluid in the cooling well.
4. Check buzz point setting.

Advanced Instruments Osmometer 3250 Specifications

General

Brand	Advanced Instruments
Model	Osmometer 3250
Category	Measuring Instruments
Language	English