Safety System - Emerson ROSEMOUNT NGA2000 HFID Instruction Manual

Instruction Manual
748297-E
June 2003
3-6

SAFETY SYSTEM

The HFID Analyzer Module safety system will
not allow ignition or continuous burner func-
tion unless the following conditions are pre-
sent:
•
The internal purge gas pressure is at
least 380 hPa - gauge (5.5 psig). (Moni-
tor display message, Purge Gas Pres-
sure in Physical Measurements menu,
for proper setting.)
•
Flow rate for purge air in is at least
16 L/min. and case pressure is greater
than 0.5 inches of water. (Monitor dis-
play message, Purge Gas (ON) in Mis-
cellaneous Control Parameters menu for
correct state. Proper sealing hardware
must be used in order to obtain the re-
quired purge air in flow rate and case
pressure).
3-6 Startup and Operation
Model NGA2000 HFID
•
Five case volumes of purge air have
been achieved and the three above
conditions are present. The time dura-
tion to achieve a safe system is a mini-
mum of 6 min. The elapsed time can be
monitored in the Technical Startup Ana-
lyzer menu. (Monitor the Purge Air
Green LED (ON), Purge Control Status
(ON), or Purge Air Alarm for indication
of the state of the safety system.)
As stated above, proper sealing hardware is
crucial to the successful operation of the
safety system. Therefore, a specific torque
sequence (shown in Figure 3-3 on page 3-8)
must be followed when the front panel of the
module is being reinstalled after removal. All
front and rear panel screws must be installed.
Do not over-torque rear panel screws.
Rosemount Analytical Inc. A Division of Emerson Process Management
Note