Vapro 5520 User manual

VAPRO®®
VAPOR PRESSURE OSMOMETER
MODEL 5520
USER’S MANUAL
M2468-4 rev B
Copy

© 1995-2004 Wescor, Inc.
All rights reserved. Printed in the United
States of America.
Wescor, Vapro, Optimol, Osmocoll and
Blow Clean are trademarks of Wescor, Inc.
Other trade names used in this manual
may be trademarks of their respective
owners, used here for information only.
The information in this manual may
change without prior notice.

TABLE OF CONTENTS
SECTION
1
INTRODUCTION
1.1 User’s Manual Overview ..............................7
1.2 Customer Service ....................................8
1.3 Vapro System Description .............................9
1.4 How the Vapro Works ...............................10
1.5 Controls and Features ...............................12
SECTION
2
GETTING STARTED
2.1 Instrument Setup Sequence ..........................17
2.2 Vapro Accessories ..................................18
2.3 Setting Up the Osmometer ...........................19
2.4 Micropipettor Information ............................22
2.5 Using Optimol®Osmolality Standards ................24
2.6 Using Osmocoll®HNL Serum Control .................26
2.7 Changing the Voltage Selector........................27
2.8 Changing Fuses ....................................28
SECTION
3
OPERATING THE VAPRO
OSMOMETER
3.1 Operation Overview .................................29
3.2 Loading Samples ...................................34
3.3 Cleaning the Sample Holder..........................39
3.4 Running the Clean Test ..............................40
3.5 Calibrating .........................................41
3.6 Standby or Waiting Periods ..........................43
3.7 SerialDataOutput ..................................44
iii

TABLE OF CONTENTS
SECTION
4
PREVENTIVE MAINTENANCE
4.1 Preventive Maintenance Overview ....................45
4.2 Removing the TC Head ..............................46
4.3 Cleaning the TC Head ...............................48
4.4 Reinstalling the TC Head ............................51
4.5 Equilibration After Cleaning ..........................53
4.6 Severe or Stubborn Contamination ....................54
SECTION
5
SOLVING PROBLEMS
5.1 Troubleshooting.....................................57
5.2 Common TC Head Problems .........................65
5.3 External Factors Affecting Precision ...................68
5.4 Deformed or Broken Thermocouple ...................69
APPENDIX A
Instrument Specifications ................................71
APPENDIX B
Accessories, Supplies, and Replacement Parts .............73
APPENDIX C
Theory of Operation .....................................75
APPENDIX D
Special Application Notes ................................81
iv

TABLE OF CONTENTS
APPENDIX E
Osmolality Standards ....................................91
APPENDIX F
Serial Data Output ......................................93
APPENDIX G
Setup Menu ......................................95
INDEX ...............................................97
v

SECTION 1
INTRODUCTION
1.1 User's Manual Overview
Thank you for purchasing the Vapro®vapor pressure osmometer.
You will find it to be a valuable investment and an important partner
in the laboratory.
The Vapro User’s Manual is your key to efficiently operating this
instrument. We recommend that you become thoroughly familiar
with the operation procedures and troubleshooting techniques
described in this manual.
Information is presented in a step-by-step format to demonstrate the
operation and care of the instrument from a first-time user’s point of
view. Once you become familiar with the operation of the Vapro
osmometer, the manual will help you maintain the instrument in a
high state of precision and reliability.
7
SPECIFICATION OF SAFE USE:
Using this instrument in a manner not specified by Wescor may
impair the safety protection designed into the equipment and may
lead to injury.
SAFE USE ENVIRONMENT:
This equipment is designed to be safely operated at 15 to 35 °C,
maximum relative humidity 80%.
FUSE: All fuses in this equipment are time-lag (Type T).
EXPLANATION OF SYMBOLS FOUND ON EQUIPMENT:
Alternating Current (AC)
I Power On
O Power off
International Attention Symbol. Calls attention to important
information and instructions in the instruction manual.
˜

SECTION 1
INTRODUCTION
1.2 Customer Service
Wescor is ready to help resolve any difficulty with the operation or per-
formance of your Vapro osmometer. If you cannot solve a problem
using the procedures in this manual, please contact us.
Customers within the United States are encouraged to contact us
by telephone. Outside the U.S., many of our authorized dealers
offer complete customer service and support. Contact Wescor by
mail, telephone, or fax at the address and numbers listed below.
WESCOR, INC
459 South Main Street
Logan, Utah 84321-5294
USA
TELEPHONE
435 752 6011 Extension 0 - Operator
171 - Orders
172 - Service
TOLL FREE (U.S. and Canada)
800 453 2725 Extension 0 - Operator
171 - Orders
172 - Service
FAX
435 752 4127
E-MAIL:
[e-mail]
WEB SITE:
www.wescor.com
8

SECTION 1
INTRODUCTION
1.3 Vapro System Description
The Vapro osmometer is an advanced electronic adaptation of the
hygrometric method of vapor pressure determination. The sensitive
thermocouple and sophisticated electronics provide the means to
measure the dew point temperature depression of a specimen with
resolution to 0.00031 °C (which equals 1 mmol/kg).
Vapor pressure and freezing point are among the colligative proper-
ties of a solution. Compared with pure solvent, these properties are
altered in proportion to the number of solute particles dissolved in
each kilogram of solvent (water in the case of biological solutions).
Thus, measuring either property is an indirect means of determining
solution concentration or osmolality.
The chief advantage of the vapor pressure method is that it does
not require alteration of the physical state of the specimen.
Concomitant benefits include:
•10 microliter sample size.
•Routine operation on micro samples of any biological solution,
including whole blood, serum, plasma, urine, and sweat, as well
as complex specimens such as tissue samples.
•None of the measurement artifacts that arise in freezing point
depression measurements due to elevated viscosity, particulate
matter, inhomogeneities, or other physical characteristics of the
sample.
•Superior reliability because the measurement involves minimal
mechanical complexity.
NOTE:
Vapro displays in Standard International (SI) units: mmol/kg. See Appendix E.
9

SECTION 1
INTRODUCTION
1.4 How the Vapro Works
A 10 microliter specimen is aspirated into a micropipettor tip. The
specimen is then inoculated into a solute-free paper disc in the
sample holder, whereupon the sample holder is pushed into the
instrument and the sample chamber is locked. Locking initiates the
automatic measurement sequence.
The sensing element is a fine-wire thermocouple hygrometer. This
is suspended in a unique, all-metal mount, which when joined with
the sample holder, forms a small chamber enclosing the specimen.
As vapor pressure equilibrates in the chamber airspace, the thermo-
couple senses the ambient air temperature, thus establishing the
reference point for the measurement. Under electronic control, the
thermocouple then seeks the dew point temperature within the
enclosed space, giving an output proportional to the differential tem-
perature.
The difference between the ambient temperature and the dew point
temperature is the dew point temperature depression–an explicit
function of solution vapor pressure.
Dew point temperature depression is measured with a resolution of
0.00031 °C. The microprocessor-controlled measurement cycle
requires 80 seconds.
Appendix C contains the theory of operation of the vapor pressure
osmometer.
10

11
TC Head and
Connector
Thermocouple and TC Mount
Thermocouple Head and Sample
Chamber Assembly

12
ENTER
SELECT
Power
VAPORPRESSUREOSMOMETER
TM
Power Indicator SELECT Keypad ENTER Keypad
Display Screen Pipette Guide
TC Head Access Cover
Sample Slide / Sample Holder Press Here to Remove
Cover

SECTION 1
INTRODUCTION
1.5 Controls and Features
INSTRUMENT FRONT PANEL
Display Screen
10 x 7 cm LCD. Displays menu selections, osmolality readings,
countdown of measurement time in seconds, operating status, fault
conditions, and other information.
SELECT Keypad
Press to call up menus and to select operation mode.
ENTER Keypad
Press to engage a selected menu item or operation mode.
Pipette Guide
Aligns and steadies the pipette for precise application of the speci-
men onto the sample disc in the sample holder.
Sample Holder
Standard sample holder for samples up to 10 microliters in volume.
Requires solute-free paper discs (provided) for use. Other sample
holders are available for special applications (see Appendix B and D).
Sample Slide
Moves the sample holder from the loading position (under the
pipette guide) to the sample chamber.
Power Indicator
The green light indicates the instrument is on.
INSTRUMENT TOP
TC Head Access Cover
Provides access to thermocouple head for cleaning and mainte-
nance. Press down on the right side of the cover to remove.
13

14
115Vac
Serial Data Port
Sample Chamber Lever
(Shown in the Open
Position)
Power Entry Module
Signal Chime
Model and Serial
Numbers

SECTION 1
INTRODUCTION
1.5 Controls and Features
INSTRUMENT RIGHT SIDE
Sample Chamber Lever
Opens and closes the sample chamber. Closing the sample cham-
ber locks the sample holder within the chamber. The chamber
should remain closed, except when loading or removing samples.
Closing the chamber initiates the measurement cycle or the
“Standby” mode (indicated by READY on the display screen) if no
sample is present.
INSTRUMENT INTERIOR
The thermocouple (TC) head and thermocouple head connector are
accessed by removing the chamber access cover from the top of the
instrument.
INSTRUMENT REAR PANEL
Signal Chime
Sounds a short chime at the conclusion of each measurement cycle
and a long chime when certain fault conditions exist. Turn the shut-
ter wheel to adjust volume.
Serial Data Port
For asynchronous serial communication with a printer or computer.
The serial port uses a DB9 connector at RS-232 voltage levels.
See Appendix F for more information.
15

SECTION 1
INTRODUCTION
1.5 Controls and Features
16
INSTRUMENT REAR PANEL (Continued)
POWER ENTRY MODULE
Accepts standard IEC 320 type power cord.
Fuse Door
Provides access for fuse replacement. See Section
2.8 for instructions.
Power Switch
Switches power on (I) or off (0).
Voltage Selector
This selector is set at the factory. If necessary, you can
set the selector to match your local power source (see
Section 2.7). Fuses must match the voltage selection.
To change fuses, see Section 2.8 and Appendix A.
115Vac
Power Switch
(I) on (0) off
Voltage Selector
Power Entry Module
Fuse Door
WARNING!
Using this equipment in a manner not specified by
Wescor may impair the provided safety protection.
WARNING!

SECTION 2
GETTING STARTED
2.1 Instrument Setup Sequence
We recommend that you follow this sequence if you are using this
instrument for the first time. Details about these operations are
found in the following sections.
1. Inspect accessories and supplies.
2. Place the instrument on a suitable work surface in an area free
from drafts.
3. Plug in the power cord and switch power on.
4. Allow for temperature equilibration (observe Temperature Drift
Scale).
5. Practice loading samples.
6. Calibrate the instrument.
7. Perform a Clean Test and clean the thermocouple if necessary.
8. Check instrument calibration and recalibrate if necessary.
9. Assay samples.
17
List

SECTION 2
GETTING STARTED
2.2 Vapro Accessories
18
The following accessories and supplies are furnished with the Vapro
osmometer:
Vapro User’s Manual
Micropipettor
Micropipettor Disposable Tips
Forceps
Paper Sample Discs
Opti-Mole®Osmolality Ampule Standards
Ampule Organizer
9/64 inch Hex Driver
Thermocouple Head Cleaning Supplies, consisting of:
Cleaning Solution
Deionized Water
Blow Clean™* (U.S. 48 states only)
Thermocouple Cleaning Solution with Anionic Detergent
In addition to the above, you need a supply of lint-free tissue paper
or cotton swabs for cleaning the sample holder between specimens.
* Compressed or liquefied pure gas suitable for blowing dust from delicate
surfaces or precision mechanisms. Available under various trade names.
CAUTION!
Never use facial or other soft tissue to clean the sample holder. Such
tissues produce excessive lint residue that will contaminate the thermo-
couple sensor.

SECTION 2
GETTING STARTED
2.3 Setting Up the Osmometer
19
Carefully unpack the instrument and compare the
contents with the packing list to be certain that
everything needed for operation is at hand.
1 Place the osmometer on a suitable work sur- face.
NOTE:
Avoid locations where instrument precision will be
altered by thermal gradients or rapid temperature
changes caused by heavy foot traffic, air vents, blow-
ers, heaters, or windows.
2 Connect the power cord to an electrical outlet that matches the voltage selected on the rear
panel. Avoid power circuits that are shared by
centrifuges, air conditioners, or other power
equipment. We recommend that you use a
power line surge protector to isolate the
osmometer from spikes and surges.
3 Verify that the sample holder is in the measure- ment position (sample slide is pushed com-
pletely into the instrument until it stops).
4 Verify that the sample chamber lever is in the closed position.
TURN PAGE TO CONTINUE INSTRUCTIONS
115Vac

SECTION 2
GETTING STARTED
2.3 Setting Up the Osmometer
20
5 Turn the osmometer on (I). The POWER indica- tor on the front panel shows green when power
is on.
The display screen will briefly show the Wescor
logo, language and unit selection, and the resident
software version. This will be followed by the word
“initialization” with a countdown timer.
To change the displayed language or units of mea-
sure, see Appendix G, Setup Menu.
NOTE:
If you open the chamber lever before the end of the ini-
tialization cycle, the warning chime sounds.
The initialization cycle establishes the reference
point for the instrument. When the initialization cycle
is complete, the display screen will appear as shown
on the left.
NOTE:
Even though the screen at this point indicates the instru-
ment is ready, calibration will not be stable until the
instrument reaches thermal equilibration (see below).
Temperature Drift Scale
Osmolality determination involves the measurement
of extremely small temperature differentials. The
osmometer is thus sensitive to ambient temperature
changes which induce internal temperature changes.
115Vac