Condair EL2 - Functional Description

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3.4 Functional description
The steam humidier Condair EL2 is a pressureless steam generator that utilizes an electrode
heating. ThesteamhumidierCondairEL2isdesignedforairhumidicationviaasteamdistributor
(steamdistributionpipe,fanunitorsteamdistributionsystemOptiSorp).
Steam generation
Any time steam is requested, the electrodes are supplied with voltage via main contactor. Simultane-
ously,theinletvalveopensandwaterentersthesteamcylinderfromthebottomviawatercupand
supplyline.Assoonastheelectrodescomeincontactwiththewater,currentbeginstoowbetween
theelectrodes, eventually heating and evaporating thewater.The more theelectrodesurfaceis
exposed to water, the higher is the current consumption and thus the steam capacity.
Uponreaching the requestedsteamcapacity,theinlet valve closes.Ifthe steam generationde-
creasesbelowacertainpercentageoftherequiredcapacity,duetoloweringofthewaterlevel(e.g.
becauseoftheevaporationprocessordrainage),theinletvalveopensuntiltherequiredcapacity
is available again.
Iftherequiredsteamcapacityislowerthantheactualoutput,theinletvalveiscloseduntilthedesired
capacityisachievedbyloweringofthewaterlevel(evaporationprocess).
Level monitoring
A sensor provided in the steam cylinder cover detects when the water level gets too high. The mo-
ment the sensor comes in contact with water, the inlet valve closes.
Drainage
Asaresultoftheevaporationprocess,theconductivityofthewaterincreasesduetoanescalating
mineralconcentration.Eventually,aninadmissiblyhighcurrentconsumptionwouldtakeplaceifthis
concentrationprocesswere permittedtocontinue.To
preventthis
concentrationfrom reachinga
value,unsuitablyhighfortheoperation,acertainamountofwaterisperiodicallydrainedfromthe
cylinderandreplacedbyfreshwater.
Control
Thesteamproductioncanbecontrolledwithanexternalcontinuouscontroller0-10V(continuous
control)orwithanexternalhumidistat(On/Offcontrol).