Emerson Rosemount Oxymitter 4000 Reference Manual page 65

July 2018
SW2 Setting
The factory sets this switch as follows:
1.
2.
Typically, the probe's sensing cell, in direct contact with the process gases, is heated to
approximately 736 ° C (1357° F). The external temperature of the probe body may
exceed 450° C (842 ° F). If operating conditions also contain high oxygen levels and
combustible gases, the Hazardous Area Oxymitter 4000 may self-ignite.
3.
4.
Read O
Once the cell is up to operating temperature, the O
1.
2.
3.
Configuration with LOI
Position 1 is HART/LOCAL. This switch setting controls the configuration of the
Hazardous Area Oxymitter 4000. The defaults cannot be changed via HART/AMS
or the LOI unless the switch is in the HART position. Placing SW2, position 1 in the
LOCAL position forces the O
switch must be in the LOCAL position or changes in SW2, position 2 will have no
effect.
Position 2 determines the O
25% O . The factory setting is 0 to 10% O
2
configured from 0 to 40% O
1 to HART and then enter the range via HART/AMS or the LOI. Do not change SW2
position 1 to LOCAL unless you want to operate in the range specified by SW2,
position 2.
WARNING
Position 3 determines the output at startup or at an alarm. The settings are 3.5 mA
or 21.6 mA. The factory setting is 3.5 mA. At startup, the current at the analog
output is 3.5 mA or 21.6 mA.
Position 4 can be used to set the heater for 115 or 220 Vac operation. This switch is
functional only when the software is set for manual voltage selection (Auto Tune =
No). Otherwise, the internal electronics auto detect the input line voltage and sets
the heater voltage accordingly (Auto Tune = Yes).
Concentration
2
To access TP5 and TP6 under the LOI module (Figure 4-2), power down the
Oxymitter 4000 and remove the LOI module. Attach alligator leads from a
multimeter across TP5 and TP6. Install the LOI module and power up the
Oxymitter 4000. Allow time for the cell to reach operating temperature. The
calibration and process gases can now be monitored. When a calibration has been
initiated, the value at TP5 and TP6 is the % O
seen on the multimeter, are:
8.0% O = 8.0 VDC
2
0.4% O = 0.4 VDC
2
HART/AMS.
Model 751. The loop-driven LCD display.
range to the setting of position 2. The position 1
2
range. This can be set to either 0 to 10% O
2
. If necessary, the O
2
. To select values within this range, set SW2, position
2
percentage can be read:
2
seen by the cell. Oxygen levels, as
2
Rosemount Oxymitter 4000
or 0 to
2
range can be
2
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