Siemens LR 460 User Manual
Page 16
SITRANS LR 460 – INSTRUCTION MANUAL
7ML19985JM01
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Air Purging System (Optional)
For more frequent cleaning, a purging system can be installed between the flange and the
horn antenna. The system provides an 1/8" inlet (female thread) on the flange where
cooling air or cleaning fluid passes through the flange and exits the inside of the horn to
clean it. The customer will supply the purging medium by a manual or automatic valve
system.
horn antenna. The system provides an 1/8" inlet (female thread) on the flange where
cooling air or cleaning fluid passes through the flange and exits the inside of the horn to
clean it. The customer will supply the purging medium by a manual or automatic valve
system.
This option is only available with the universal flange for purging shown on page 17.
1
•
The purge connection is closed
by the manufacturer, using a 1/8"
plug.
by the manufacturer, using a 1/8"
plug.
•
When the plug is removed to
connect a purging system, the
operator is responsible for
ensuring that the purging circuit
conforms to "Ex" requirements:
connect a purging system, the
operator is responsible for
ensuring that the purging circuit
conforms to "Ex" requirements:
for example, by fitting an NRV
valve.
valve.
Notes:
• The Air Purge feature should not be activated with a dust cap in place.
• Purge duration, pressure, and interval, will vary with each application. It is the user’s
• Purge duration, pressure, and interval, will vary with each application. It is the user’s
responsibility to determine the requirements depending on the application and
cleaning required.
cleaning required.
• Short duration bursts of high pressure provide more effective cleaning than
continuous low pressure air.
• Some dust particles are highly abrasive and can be drawn into the inside of the horn
during purge cleaning, damaging the internal PTFE emitter of the antenna. A
replacement kit is available from your local Siemens Milltronics representative.
replacement kit is available from your local Siemens Milltronics representative.
• It is the customer’s responsibility to ensure that any vacuum or pressure in the
measured vessel is maintained, considering the hole that passes through the
process connection and SITRANS LR 460 antenna system.
process connection and SITRANS LR 460 antenna system.
Recommendation for
effective cleaning
Air Consumption
(Flow rate versus applied pressure)
Pressure: 90 to 110 psi
Air Pressure
Approx. inlet volume flow rate
20
5 SCFM
40
6 SCFM
Inlet flow: 10 SCFM
1
60
8 SCFM
80
9 SCFM
90
10 SCFM
1.
SCFM (standard cubic feet/minute) referenced to 14.7 psia, 68°F and 36% relative humidity (RH).
purged process
connection with factory-
installed 1/8" NPT plug
connection with factory-
installed 1/8" NPT plug