The knobs are graduated with an arbitrary 1-9
scale. Turning the knob to a higher number
increases the stirrer speed.
Safety Advice
❖
Do not use the instrument to heat
inflammable liquids
❖
Never lift or carry the instrument until it has
been switched off and allowed to cool for at
least 30 minutes. The hot warning light will
give guidance.
❖
The unit should be carried using both hands
with the fingers under the side edges.
❖
Never move or carry the unit with containers
on the top plate or while still connected to
the mains supply.
❖
There is a danger of liquid spillage if
containers are over-filled and stirred at high
speed. Always build stirrer speed slowly and
never stir more rapidly than necessary.
❖
NEVER place a cold glass vessel onto a
hotplate which is already hot.
Cleaning and Care
Before attempting cleaning ensure that the top
is cool and disconnect from the mains electricity
supply.
The metal casing should be cleaned using a
damp cloth and a mild detergent solution.
The metal top plate should be cleaned using a
damp cloth and a mild detergent solution.
Cleaning is made easier if spillage are attended
to promptly. In any case, spillage of acids and
alkalis MUST be removed immediately as these
chemicals can attack and damage the surface of
the aluminium alloy. Ensure that the appropriate
safety precautions are observed.
Preparation of Media
Take particular care when heating liquids having
a high viscosity. Viscous liquids can act as
thermal insulators and can cause thermal
breakage of the glassware. This is very important
with media solutions as the viscosity will usually
increase as the temperature rises.
❖
Check that the stirring action is sufficient to
agitate the whole of the liquid. Unstirred areas
in the liquid can result in uneven heat transfer
and “hot spots” in the glassware. This can
induce thermal stress and so cause failure.
❖
Check the stirring action regularly to ensure
that it remains adequate as the viscosity of the
solution increases.
❖
Always use the largest magnetic follower
possible and, if necessary, use a mechanical
overhead stirrer.
❖
Do not use glass vessels with thick walls, e.g.
Pyrex Heavy Duty Ware or standard beakers
and flasks having capacities of 5 litres or
greater.
❖
NEVER heat glass bottles on a hotplate.
❖
Ensure that the heat is built up slowly to avoid
localised overheating.
❖
Ensure the glassware is completely free from
scratches or other defects.
❖
Place the hotplate in a tray large enough to
contain the liquid in the event of glassware
failure.
❖
Wear the appropriate safety clothing - e.g.
gloves, goggles, protective apron etc.
Accessory
A rod is available to support apparatus used with
the instrument.
The rod is supplied with a mounting bracket that
can be mounted behind any of the 3 plate
positions. The instrument is provided with pre-
drilled holes to accept the mounting bracket.
To fit the rod to your instrument, first isolate
from the mains supply and allow to cool. Attach
the bracket to the rear or the instrument with
the screws provided and then simply screw the
threaded end of the support rod into the
bracket.
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