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OXYGEN PROBE SETUP
The NXCESO2 oxygen probe provides continuous oxygen (O2) content and stack temperature read-
ings from the stack. When properly connected and configured to the PPC4000, it allows the
PPC4000 to trim the air or fuel servo to achieve optimum combustion. Refer to earlier sections of
this bulletin for information regarding installation and wiring of the NXCESO2.
To add O2 trim to the PPC4000 operation the NXCESO2 oxygen probe must be commissioned with
the air and fuel servos. Commissioning with O2 can be done after the servos are commissioned or
can be done along with the initial servo commissioning. During the commissioning process the
PPC4000 will save the target O2 level at each profile setpoint. During normal operation the PPC4000
will trim either the air or fuel servo to maintain this established O2 target level. O2 trim occurs from
low fire (p03) through high fire (pHigh). O2 trim will take effect only after all profile setpoints are
commissioned with an O2 level. If O2 trim is enabled through the user interface and the system has
yet to be commissioned to set the O2 levels, then O2 trim will be ignored.
The PPC4000 provides an extensive sub menu where the installing engineer must set a number of
key boiler parameters relating to O2 trim operation. The O2 SETUP is passcode protected. All
parameters in the O2 SETUP menu are readable but do require at least the Adjust Ratio passcode to
be enabled before any parameter can be modified. The passcode will remain enabled for 5 minutes
after the last key press. Any change to the O2 SETUP menu will take effect immediately.
In the top layer menu scroll to O2 SETUP and press NEXT to enter this sub menu. This menu pro-
vides the means to enter all O2 parameters relating to trim. If not enabled, when pressing the MDFY
key, the user will be diverted to the passcode screen where at least the Adjust ratio code must be
entered.
Most menu items are burner / boiler dependent and it is important the installing / commissioning
engineer be familiar with the burner / boiler to understand its capabilities and limitations.
Menu item
Value
Description
O2 OPERATION
DISABLED
O
2
trim is not enabled. No further menu items are
displayed.
CONTROL
O
2
trim enabled for profiles selected. All menu items are
displayed. The O2 level is shown in the top layer.
MONITOR
Allows O
2
level to monitored with trim being disabled, but
the O
2
level is shown in the top layer.
CALIBRATE
NOW>
When the NEXT key is pressed a calibrate signal is sent to
the NXCESO2 probe. The function is operational only
during STANDBY and PURGE.
ASSIGNMENT
4,3,2,1
User selects which profile O
2
trim is applied.
FUEL TYPE (X)
NONE
FUEL TYPE for each assigned profile is required to
calculate boiler efficiency. The fuel type selected
determines the constants used. Default is NONE.
NAT.GAS
OIL #2
OIL #6
LNG
COKE
METHANE
PROPANE
To use oxygen trim properly, the installing personnel must be completely familiar with and know the
limitations of the burner / boiler equipment at hand. It is not the purpose of the O2 probe and associ
ated trim algorithm in the PPC4000 to extend the burner/boiler to operate beyond its design limita
tions. The purpose of O2 trim is to maintain a consistent fuel/air ratio through variations in
temperature, humidity and fuel BTU content. When properly setup according to these instructions,
O2 trim will result in more heat output per BTU input and increased combustion efficiency and fuel
savings will be realized. It is expected the installing personnel read and understand the O2 SETUP
menu items and commission the O2 probe in accordance with this bulletin.
