Emerson NGA2000 PMD Manual Do Utilizador
Instruction Manual
760007-A
July 2003
July 2003
2-2 Installation Rosemount Analytical Inc. A Division of Emerson Process Management
Model NGA2000 PMD
2-3 LOCATION
Install the Analyzer Module in a clean, non-
hazardous, weather protected, vibration free
location free from extreme temperature varia-
tions. For best results, either install the mod-
ule near the sample stream to minimize
sample transport time or supply a flow greater
than necessary and route only the appropriate
amount through the Analyzer Module.
hazardous, weather protected, vibration free
location free from extreme temperature varia-
tions. For best results, either install the mod-
ule near the sample stream to minimize
sample transport time or supply a flow greater
than necessary and route only the appropriate
amount through the Analyzer Module.
Observing these requirements are critical.
Note the following:
Note the following:
• Excessive vibration can cause a noisy
readout. To minimize vibration effects,
the detector/magnet assembly is envel-
oped in a shock-mounted compartment.
the detector/magnet assembly is envel-
oped in a shock-mounted compartment.
• The user should ensure, when making
any internal electrical connections, that
no cables are placed in contact with the
detector assembly or associated internal
sample inlet and outlet tubing.
no cables are placed in contact with the
detector assembly or associated internal
sample inlet and outlet tubing.
• Magnetic susceptibilities and partial
pressures of gases vary with tempera-
ture. Permissible ambient temperature
range is 32
ture. Permissible ambient temperature
range is 32
°F to 113°F (0°C to 45°C).
• The interior of the Detector Assembly is
maintained at approximately 144
°F
(62
°C) by an electronically controlled
heater. Prior to entering the detector
assembly, the sample is heated in a
coiled tubing to match the detector's
temperature.
assembly, the sample is heated in a
coiled tubing to match the detector's
temperature.
2-4 GASES
a. Requirements
Calibration Gases
Analyzer Module calibration requires the
establishment of zero and span calibra-
tion points. This requires a zero standard
gas to set the zero point span gas to es-
tablish a calibration point at or near the
upper range limit.
establishment of zero and span calibra-
tion points. This requires a zero standard
gas to set the zero point span gas to es-
tablish a calibration point at or near the
upper range limit.
An oxygen-free gas, typically nitrogen, is
required for use as the zero standard gas.
Recommendations for span calibration
gases, bases on various operating
ranges, are tabulated in Table 3-4 on
page 3-10. Air (20.93% oxygen) can be
used as span gas regardless of the
ranges used for sampling, although very
low ranges may lose accuracy.
required for use as the zero standard gas.
Recommendations for span calibration
gases, bases on various operating
ranges, are tabulated in Table 3-4 on
page 3-10. Air (20.93% oxygen) can be
used as span gas regardless of the
ranges used for sampling, although very
low ranges may lose accuracy.
Sample Gas
Sample gas should be non-flammable.
Temperature
Sample temperature at the inlet should be
from 50
from 50
°F to 150°F (10°C to 66°C). A
maximum entry temperature of 110
°F
(43
°C) is recommended to prevent cool-
ing of the sample and possible internal
condensation. Such condensation could
damage some components of the Ana-
lyzer Module. This recommendation can
be ignored if a thoroughly dry sample is
examined.
condensation. Such condensation could
damage some components of the Ana-
lyzer Module. This recommendation can
be ignored if a thoroughly dry sample is
examined.
Pressure
Sample exhaust pressure limits are -5 to
10 psig (-345 to 690 hPa-gauge). Normal
operation is in the positive range, be-
tween 0 and 10 psig (0 and 690 hPa-
gauge). Negative gauge pressures are
not normally recommended, but may be
used in certain special applications.
10 psig (-345 to 690 hPa-gauge). Normal
operation is in the positive range, be-
tween 0 and 10 psig (0 and 690 hPa-
gauge). Negative gauge pressures are
not normally recommended, but may be
used in certain special applications.
To prevent over-pressurization, insert a
pressure relief valve into the sample inlet
line. A check valve should also be placed
in the outlet line if the Analyzer Module is
connected to a manifold associated with a
flare or other apparatus that does not op-
erate at atmospheric pressure.
pressure relief valve into the sample inlet
line. A check valve should also be placed
in the outlet line if the Analyzer Module is
connected to a manifold associated with a
flare or other apparatus that does not op-
erate at atmospheric pressure.
The outlet port is commonly vented to the
atmosphere. Any change in barometric
pressure has a directly proportional effect
on the indicated percent of oxygen, and
should be neutralized through manual or
computer correction of data. Note the fol-
lowing example:
atmosphere. Any change in barometric
pressure has a directly proportional effect
on the indicated percent of oxygen, and
should be neutralized through manual or
computer correction of data. Note the fol-
lowing example: