Siemens LMV5 Quick Start Manual page 97

Menu Path Parameter
O2 Content Air
Type ofAirChange
O2 OffsetGas
or
O2 OffsetOil
Params & Display>
O2ContrGuard>
Gas/Oil Settings
LoadCtrlSuspend
FilterTimeLoad Filt Ti
CombEfficiency
Params & Display>
O2ContrGuard>
Gas/Oil Settings>
ManVar O2 Ctrl
Process Data
LMV5 QSG Rev 4
U = User O = OEM
S = Service
Defines the O2 content of the combustion air. The LMV52 must see this value during purge. This value can
O
be adjusted if O2 enriched air is used. Range = 0 to 30%, Def = 20.9%.
When firing gas select like P air (change in airflow does affect gas flow)
When firing oil select like theory (change in airflow does not affect oil flow)
Def= like theory
During a load change, this offset temporaily increases the O2 setpoint.
When the change in load is completed, the O2 setpoint will revert to the O2 control curve. Range = 0-5%
Def / Typ = 0%. However, if the burner tends to go below the O2 Monitor curve during load changes, then
this setting can be increased (0.5% or more) to eliminate O2 readings below the O2 Monitor curve.
During a load change, the O2 trim control will lock, meaning that it will "remember" where the air influenced
S
actuators (usually just the air actuator) tracked the last time the burner went through a similar load change.
When locked, the O2 trim will not be making real time adjustments. This locking during load changes is
referred to as precontrol. This setting enables adjustment of what the LMV52 considers as a load change
that will lock the O2 trim. Adjustment is generally not recommended, however reducing this setting can help
deactivation in some circumstances. Range = 0-25% Default & Typ = 5%
After a load change that locks the O2 trim control, a time factor is applied that makes the LMV wait to unlock
L d th t i the trim control. This setting adjusts the unlocking time. Adjustment is generally not recommended, however t l Thi
increasing this setting can help deactivation in some circumstances. Range = 4-10 Def /Typ = 5
Calculated Combustion Efficiency, based on wet O2 levels in the stack,
combustion air temperature, and flue gas temperature.
This value represents how much the O2 control is trimming from the base O2 Ratio control curve. When this
U
value is decreasing it means that the LMV is closing the air influenced actuators to compensate for a higher
than setpoint O2 value in the stack. When this value is increasing, the LMV is opening the air damper
approaching the O2 ratio control curve. When the LMV has compensated as much as possible for a lean
condition, value will be about 15%, and as much as possible for a rich condition, value will be about 52%.
Descriptions / Notes
tti dj t th l ki ti Adj
Sec 4 Pg 41
t t i ll t d d h
www.scccombustion.com
60-62