V&P Scientific, Inc.
4
Technical Note 083B
4)
To remove the VP 758-5 series Reservoir from the VP 767-5A motor, lift slightly up on the end of
the Reservoir opposite to the Sealed Bearing and pull out.
5)
The VP 767-5A motor is powered by a DC Motor speed controller. The auto-switchable controller
is powered by 110 or 240 VAC at 60 or 50 Hz.
6)
Do not use the speed controller to stop the stirrer. Use the on/off switch.
7)
Do not operate dry as this will wear out the seal. Always operate with liquid.
8)
Operate at speeds and liquid levels that do not aerosolize the liquid. At lower liquid levels use
slower speeds. The maximum speed is 1,500 RPM and is set at the factory.
9)
To lengthen the life of the seal, operate at the lowest possible speed that keeps particles in
suspension. In addition, operate only when needed as this will prolong the life of the seal.
CARE
1)
The VP 758 series Bubble Paddle Reservoir can be cleaned with detergents and rinsed with
distilled water and or ethanol/isopropanol. It can also be sterilized by autoclaving if necessary.
These operations should be done while the reservoir unit is assembled (drive shaft and sealed
bearing in place). Do not pull the drive shaft out of the sealed bearings to release the bubble
paddle. This is not recommended because of the risk of damaging the seal. The reservoir can also
be disinfected by soaking in a 10% bleach solution for 5 minutes followed by sterile water rinses
and an additional rinse in alcohol.
2)
Replacement sealed bearing units (VP 758-3S, see Figure 5) are available in the event the reservoir
begins to leak. To remove sealed bearing unit from the reservoir, remove the screw at the
bottom
of the reservoir
and pull out the sealed bearing unit. It is secured in the reservoir by a friction fit
from two O rings. The set screw at the top of the sealed bearing unit should
NOT
be removed.
3)
Clean the bearing hole and apply a thin coat of silicone grease. Hand press a new VP 758-3S into
the reservoir. Line up the slot on the drive shaft with the end of the bubble paddle. Insert and
tighten screw at bottom of reservoir to lock the sealed bearing unit in place. Send the leaky
sealed bearing unit to V&P for repair.
Figure 5. Replacement Sealed Bearing Unit (VP 758-3S)
