Global 5120 - 3.2.5 Spark Ignition (SI) System

GlobalPowerTechnologies  3-9
5120
2) Checktheairlterscreenforanytearsorholes.Ifanyarefounditshouldbereplaced.
3) Checktheburnerscreen.
4) Checktheceramicspacer.
3.2.5 Spark Ignition (SI) System
Thesparkignitionsystemconsistsof3majorcomponents.
1) Thehighvoltagesparkelectrodewhichignitesthegas.
2) Thepressureswitchwhichsensesgaspressure.
3) Thecontrolmodulewhichgeneratesthehighvoltagetotheelectrodeandalsohascon-
trolfunctions.
3.2.5.1 SI Theory of Operation
WhenfuelissuppliedtotheTEGthepresenceoffuelpressurecausesthepressureswitch
toclose.This,combinedwiththeabsenceofheatsensedbythesparkelectrode,causesthe
controlmoduletogenerate12kVoltsparks.Thesesparksarcfromthesparkelectrodetothe
combustionchamberwallandignitethefuelpresentintheburner.Onceignitionbegins,the
presenceofheatsignalsthecontrolmoduletostopsparkingwithinveminutes.
ThecontrolmodulecontainsaD-size2volt,2.5amp-hourre-chargeablebatteryandaconstant
potentialbatterycharger.Anewfullychargedbatteryprovidesabout16hoursofcontinuous
startingcapabilitywithoutrecharging.Twenty minutes of recharging is enough foronestart
cycle.Ifthebatteryiscompletelydischargeditwillrequirefteenhourstofullyrecharge.
3.2.5.2 SI Maintenance
WARNING: To prevent high voltage shock remove the orange wire from the pres-
sure switch and make sure it can not come into contact with other electrical
connections.
1) ChecktheoperationoftheSIsystemasfollows:
a) RemovetheSparkElectrodebylooseningthewing-nutandslidingtheelectrode
out.
b) Inspecttheelectrodeforanycracksintheceramicrod.Ifanycracksarefound
theelectrodemustbereplaced.
c) Slidetheelectrodebackintopositionuntilitstops,thenpullitback3to6mm(1/8
to1/4”).Theceramicrodshouldextendabout25mm(1”)fromtheholdingscrew.
d) Tightenthewing-nutonlyuntilitissnug.DONOTovertightenortheceramicrod
willcrack.
e) Loosentheorangeandbrownwireconnectorsfromtheterminalsonthepressure
switchandthenshortthecircuitbetweenthetwoterminals.Arcingshouldoccur
inthecombustionchamber(makingaclickingnoise)attherateofonepersec-
ond.
f) Ifarcingoccursthesystemisfunctioningwell.
2) Checkthepressureswitch.Itshouldcloseatapressureof13.8kPa(2psig)andopen
at6.9kPa(1psig).Replacethepressureswitchifnecessary.