Pfeiffer Vacuum OKTA 2000 ATEX, Operating Instructions Manual

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Classification Description
X Special operating conditions must be observed! Special conditions and notes in
the operating instructions apply.
Ta Permissible ambient temperature for operation of the vacuum pump prescribed
on the rating plate.
Tbl. 4: ATEX designations
2.4.2 Potential hazards
The ignition hazard assessment for the roots pumps in the ATEX series was performed in accordance
with the harmonized standard ISO 80079-36 (Non-electrical equipment for explosive atmospheres - Ba-
sic method and requirements). This assessment includes the identification of hazards described as fol-
lows which will not occur if the system is operated properly with the respective safety measures.
Potential
hazard
Occurrence due to Safety measures
Hot surfaces Heating up of compo-
nents due to compression
work and friction
When used as intended, all surface temperatures are be-
low the measuring gas temperature in the exhaust chan-
nel.
Induction of eddy cur-
rents when the magnetic
coupling slips through
● Note the information to avoid this in the operating in-
structions.
Hot gases Compression of the re-
quired gases
● Measure the gas temperature in the exhaust channel
using the supplied thermometer and evaluate the
temperatures.
● Note the information in the operating instructions of
the thermometer.
Mechanical
sparks
Contact of the pistons in
the suction chamber
The air gaps for the maximum gas temperature are de-
signed taking into account a safety factor.
Electrical
sparks
Electric motor The use of an explosion-proof electric motor is prescri-
bed.
● Observe the marking on the motor rating plate.
Static elec-
tricity
Vacuum pump not earth-
ed
● Integrate the vacuum pump in the equipotential
bonding at the installation location.
Chemical re-
action
Between the process gas
and lubricant or between
the process gas and
components that are part
of the housing
● Evaluate the process and avoid hazardous process
conditions.
Zone en-
trainment
due to leaky vacuum
pump
The vacuum pump underwent a final inspection with heli-
um leak test within the framework of a production control
(leakage rate < 1 × 10 -6 Pa m 3 /s).
Tbl. 5: Potential hazards
2.4.3 Safety measures
► Observe and implement the following safety measures for safe operation of the roots pump in ac-
cordance with the respective device category:
Safety
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