Watson-Marlow 620RA - Manual (Page 4)

ATEX: Watson-Marlow 620RA, 620REA and 620RE4A pumpheads User Manual 4
WARNING! Do not run dry for excessive periods. Roller and tubing
temperatures can exceed normal operating range.
WARNING! Do not run pumphead against a dead end condition (closed
discharge). This can lead to excessive roller and tubing temperatures and
pressures in excess of the limits in the table above.
When two or more items of ATEX equipment are combined, the permissible operat-
ing envelope will be determined by the narrowest range after considering all values
for a given parameter.
5 Potential pump hazards
As part of the requirements of 94/9/EC all potential hazards, including expected
malfunctions, have been identified and subjected to a risk assessment. In order to
prevent these ignition sources becoming effective a number of changes have been
implemented. In addition to engineering modifications, the changes include addi-
tional operating instructions in order to specify correct usage in hazardous locations.
Please refer to Sections 6 - 10 for further details.
Recognised ignition sources
Surface temperatures of rollers and spindles
Tube burst and subsequent spilling of pumped fluid
Mechanical failure of rotor hub
Exothermic chemical reaction
Electrostatic discharge
Bearing failure
Spring failure