Introduction and Safety
12
236 Series Twin-Screw Pump -
Installation, Operation & Maintenance Manual
3)
ATEX Measures
3.1 Installation and connection of pump
(Measures depend upon category.)
3.1.1
Category 3
1
Stay within the maximum permissible temperature of the pumped fluid on the order data sheet.
2
Prevent overheating when operating in a circulating system by routing the return line from the
safety valve to the tank not into the suction pipe
3
For couplings with coupling guards:
a. Only use guards made from electrically conductive materials
b. Secure the setscrews to fix the coupling halves to the guards with medium strength
thread retaining compound.
c. For aluminum guards, remove swarf and dirt from coupling guard
4
Ignition protection type is c = structural safety. (No additional monitoring equipment is required.)
5
For Pumps with motors supplied by the operator, motors must correspond to the requirements in
the explosion hazard area (group and category).
6
Earthing Terminals must be provided for pump units, including base plate and motor.
3.1.2 Category 2
1 Ensure there is monitoring equipment to prevent dry running. (ex. Tank level switch)
This equipment shall have a suitable level of reliability and installed with established safety
principles able to withstand expected influences during operation. This equipment shall provide
adequate warning that dry running can develop, must be capable of being checked at suitable
intervals and include the detection of loss of safety function. The equipment manufa
cture’s use
instructions shall specify the interval between periodic maintenance checks and include advise on
methods for detecting failure modes and actions to be taken to remedy. (Ref. EN 80079-37
Clause 6.5.1)
2 Ensure there is monitoring equipment to avoid overheating.
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If the system controller in not suitable for monitoring, install power monitor.
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Set monitoring according to:
The pumping parameters
The characteristic curve of the pump
The motor manufacturers’ specifications
