LW Scientific Combo V24 - Manual (Page 3)

P. 770.270.1394 F. 770.270.2389 865 Marathon Parkway Lawrenceville GA 30046
Reading Microhematocrits
Care, Maintenance, Trouble-Shooting
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Use only quality test tubes. Lower-quality plastic or glass tubes may fracture and release their contents into the tube
chamber
Never force a tube into the tube shields. Some plastic conical test tubes are too large and should not be used.
If you purchased a microhematocrit rotor, it includes a Reader Disc, which allows the tubes to be read directly from the rotor.
Because of the safety issues with high g-forces in a centrifuge, it is recommended that rotors be inspected every 6
months for corrosion and fatigue. If there is any indication of wear, the rotor should be removed from service. Contact
LW Scientific for return instructions, so the rotor can be evaluated by an LW Scientific technician for repair or replace-
ment. It is also recommended that after 2 years of service rotors and tube shields be returned to LW Scientific for
inspection. Following these procedures will ensure safety of lab personnel as well as extend the life of the centrifuge.
Light comes on - Will not spin: Check to make certain the lid safety switch (near the back right hinge) is engaged.
With the power on and the timer set, depress the button with your finger. If the rotor spins, turn the safety switch button
counter-clockwise to raise the height and allow it to contact the lid when it is closed.
No light - Not spinning: Confirm that your power source is working. Check the 8 amp fuse and replace if the filament
is broken. Speed slows down or stops...the brushes may need to be replaced on the motor after 1000 +/- hours of use
if speeds have decreased. Contact LW Scientific to purchase new brushes (part #CMP-BRSH-PR77).
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After the rotor has stopped, remove the cover plate by unscrewing the chrome thumbscrew and lifting the cover plate
straight up.
Place the reader disc over the hematocrit tubes, and adjust the disc until the 0% line is lined up with the bottom of the fluid
in the tube to be read.
While keeping the 0% line positioned at the bottom of the fluid, turn the disc until the 100% line aligns with the top of the fluid.
Read the separation line in the middle for your microhematocrit results.
With proper care and maintenance, the Combo V24 centrifuge will
provide years of laboratory grade service. Please follow these
recommended guidelines:
Never hang a tube by its cap. Always make sure the tubes are supported by the bottom of the shield, or with a
rubber cushion.
Use only 75mm capillary tubes with the 24-place hematocrit rotor.
Clean the inside of the centrifuge regularly. Always unplug electrical power before cleaning. Whenever there is a tube
breakage or a spill, it is recommended that the inside of the centrifuge be cleaned, and if possible, disinfected (do not
immerse the electrical components in any liquid).
Motor and electrical maintenance: The Combo V24 utilizes a brushed motor, which includes bearings that are
permanently lubricated. Likewise, the electrical components were designed for high reliability and should not need
regular service, other than brush replacement. However, if repairs should be needed, please contact LW Scientific,
Inc.
If the centrifuge will no longer maintain speed, inspect and/or replace the brushes. When inspecting/replacing
brushes, always blow out the motor/brush area with canned air. Excessive dust, dirt, and hair can interrupt the
brush contact and decrease performance.
If you find it difficult to change rotors, apply a small amount of grease to the shaft of the motor or to the core of the rotor. Do
not use oil or spray lubricants such as WD-40.
NOTE: Plastic tube shields should be replaced at least once a year. Tube shields should be inspected once a month for
wear or damage. Tubes that are being used in high volume should be replaced every three months or sooner.