Varian HS452, Instruction Manual

Page: 22 / 45

TECHNICAL INFORMATION
STOPPING THE PUMP
There are no special procedures for switching the
pump off; it needs only to be disconnected from
the electric power by means of the bipolar switch.
When the pump is stopped, the anti-suckback de-
vice makes it possible to maintain vacuum in the
vessel connected on the inlet flange of the pump.
If the pump is expected to be stopped for a lengthy
period, or in any case if it has pumped in large
amounts of vapors, it is good practice to run it with
the gas ballast open and the inlet line closed for a
few minutes before switching off in order to limit
the risk of corrosion or scaling due to pollution of
the oil by condensed vapors.
SAFETY RULES
Personnel responsible for pump operation and
maintenance must be well-trained and must be
aware of the accident prevention rules.
The accident prevention precautions contained in
this section must be respected at all times during
operation and maintenance of the pump to avoid
damage to operators and to the pump.
These precautions are provided in the form of
WARNING and CAUTION notes.
,
WARNING!
Operating procedures, technical information and
precautions which, if not respected and/or imple-
mented correctly may cause body harm to opera-
tors.
CAUTION
Operating procedures, technical information and
precautions which, if not respected and/or imple-
mented correctly may cause damage to the pump.
WARNING NOTES
,
a. Death may result from contact with high volt-
ages. Always take extreme care and observe
the accident prevention regulations in force.
b. Always disconnect the power supply to the
pump before maintenance work. Place a spe-
cial warning signs over the power supply
breaker switch: MACHINE UNDERGOING
MAINTENANCE - DO NOT POWER ON.
c. If you are performing maintenance after the
pump has been operating for a considerable
time, allow sufficient time for it to cool as the
external surface temperature may be in ex-
cess of 60 °C.
d. Failure to provide the pump with an earth
connection may cause serious damage to op-
erators. Always ensure that there is an earth
connection and that it complies with the stan-
dards.
e. When cleaning the pump and its component
parts, avoid the use of flammable or toxic sol-
vents, such as benzin, benzol, ether or alco-
hol. The recommendation is to use a soap and
water solution, preferably in ultrasound wash-
ing machines, taking care to dry all the
cleaned parts at temperatures under 100 °C in
order to eliminate residual moisture.
f. Prolonged overloads or breakdowns may
cause the electric motor to overheat, and to
release noxious smoke; remove the power
immediately as a precaution and do not ap-
proach the pump at least until you have pro-
vided ventilation to drive out the smoke. Take
care not to breathe in the fumes remaining in-
side the pump in the course of repair work.
g. In case of fire, do not throw water on the
pump. Switch the power off and use CO
2
ex-
tinguishers.
h. Carefully inspect the flanges to ensure that
there are no dust, oil, dirt or defects of the
mating surfaces, before making the required
connections.
i. Ensure that all joints and couplings are locked
correctly before starting the pump again after
repair work.
j. Do not wear any objects that may become en-
tangled in the mechanisms and/or act as con-
ductors (chains, bracelets, etc.).
k. Ensure that the tools to be used are in perfect
working condition and have insulating grips,
where necessary. Check that the insulating
material of the cables and that the conductors
of the test equipment do not show any signs
of damage.
17 87-900-978-01(D)