LMVSeriesTechnicalInstructions
DocumentNo.LV5‐1000
SCCInc. Page25 Section4
1. Ifpossible,shutofftheburnerswitch.LettheburnergetbacktoPhase12(standby).
2. Accessthecoldstartparametersthrou ghthefollowing menupath:
Params&Display>LoadController>ColdStart
SetparameterThresholdOntotheminimumpermissibletemperaturewheretheburnercanbe
released to modulate.Below this temperature, cold start will engage on initial startup (not
during normal operation).Set ThresholdOff to a temperature higher than ThresholdOn. If
already engaged, cold start will disengage at the ThresholdOff temper
ature.Setting
ThresholdOnandThresholdOffisrequiredforcoldstart.
NOTE: Parameters ThresholdOn and ThresholdOff are percentages based on the current
setpoint (W1).If an additional temperature sensor is used on a steam boiler, ThresholdOn
andThresholdOffwillbebasedonparameterSetpAddSensor.
3. For a steam boiler that is on a common header with other steam boilers, an additional
temperaturesensorisrequiredforcoldstart.ThiswilltypicallybeaPt1000orNi1000RTDwired
to terminal X60.Pt100 is possible but not recommended.Choose the appropriate sensor via
parameterAdditionalSens.
4. Therearefourbasicwaysthatthecoldstartcanbeset.Theseare:
a. BasicLowFireHold
The LMV5 will be held at low fire until the ThresholdOff temperature is reached, and
then the LMV5 will be released to modulate. This “hold” will re‐engage when the
temperaturefallsbelowtheThresholdOnvalue.ParameterStageLoadmustbesetto0.
b. Temperature‐basedSteppingSt
art
The LMV5 will be held at low fire until a certain temperature change is detected
, and
then a step up in burner output (load) will be taken. This continues until the
ThresholdOff temperature isreached.This willachievethe ThresholdOff temperature
fasterthanabasiclowfirehold.
ParameterStageLoadmustbesettoa valuegreater
than 0, since the step‐up in load is determined by this parameter.Parameter
StageSetp_Modmustalsobesettodeterminetheamountoftemperatur echangethat
willtriggerastep‐upinload.ParameterMaxTmeModshouldbesettoahighnumber
(30min)so
thatithasnoeffect.
c. Time‐basedSteppingStart
TheLMV5willbeheldatlowfireuntilacertaintimeelapses,andthenastep‐upinload
willbetaken.ThiscontinuesuntiltheThresholdOffvalueisreached.StageLoadmust
be set to a value greater than 0, sinc
e the step‐up in load is determined by this
parameter.ParameterStageSetp_Modshould besettoahighnumber(80%)sothatit
has no effect.Parameter MaxTmeMod is set to determine how much time should
elapsebeforethenextloadstepistriggered.
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