Siemens LMV5 Quick Start Manual page 95

Menu Path Parameter
O2 Control
Params & Display>
O2ContrGuard>
Gas/Oil Settings
O2 Monitor
P Low-Fire
I Low-Fire
Tau Low-Fire OEM
Params & Display>
Tau Low-Fire
O2ContrGuard>
Gas/Oil Settings>
P High-Fire
Control Param
I High-Fire
Tau High-Fire OEM
Tau Low-Fire
LMV5 QSG Rev 4
U = User O = OEM
S = Service
This is where the O2 setpoint curve or "trim" curve is input. NOTE : The ratio curve and O2 guard curve
S
must be set before this curve is entered. The O2 setpoints are set at each point on the ratio curve that was
set previously. It is highly recommended that at least 10 points be input on the ratio curve prior to setting the
O2 setpint curve. When O2 trim is used, the ratio cuve should be set about 2% O2 leaner that it would be
normally. The LMV52 will drive to the point on the ratio control curve when it is selected, and the technican
will have to press enter when the O2 value stabilizes. This is done to measure the gas velocity from the
burner to the sensor at that specific point. The technican will then have to back the air actuator down its
curve (while the fuel actuator does not move) by increasing the StandVal number. When the technican
achieves the desired O2 level, the point can be saved.
This point must be 0.5% O2 above the O2 Monitor curve and 1.0% O2 below the O2 lean curve.
This is where the O2 Monitor curve or "rich" curve is input. This can be thought of as a low O2 alarm point.
NOTE : The ratio curve must be set before this curve is entered. The O2 Monitor points are set at each point
on the ratio curve that was set previously. This is usually set as rich as the burner can safely operate. As a
general guideline, the burner should not be smoking or having CO higher than 400ppm at any of the O2
Monitor points. The O2 Monitor points can be directly input as a %O2 (at O2-MinValue) or the burner can be
"probed" by starting at a point on the ratio control curve and backing the air actuator down its curve while
holding the fuel actuator constant. This is done by increasing P-air man.
After a lower than normal but still safe O2 value is achieved, the point can be stored.
These six O2 parameters make up the Low Fire and the High Fire PID control response parameters of the These six O2 parameters make up the Low-Fire and the High-Fire PID control response parameters of the
S
O2 trim (Tau is essentially D). These parameters are all automatically adjusted during the O2 setup
procedure. While it is possible to manually adjust some of these parameters, it is not recommended to do
O so.
P Low-Fire - Range = 3 to 500%, Def = invalid
U
I Low-Fire - Range = 0 to 500 sec, Def = invalid
Tau Low-Fire - Range = 1 to 27 sec, Def = invalid (must be set automatically)
Tau Low-Fire OEM - Range = 1 to 27 sec, Def = invalid (can be set manually)
S
P High-Fire - Range = 3 to 500%, Def = invalid
I High-Fire - Range = 0 to 500 sec, Def = invalid
O
Tau High-Fire - Range = 1 to 27 sec, Def = invalid (must be set automatically)
Tau Low-Fire OEM - Range = 1 to 27 sec, Def = invalid (can be set manually)
U
Sec 4 Pg 39
Descriptions / Notes
60-62
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