Condair CP3 - 3.4 Functional description

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3.4 Functional description
The steam humidier Condair CP3 is a pressureless steam generator that utilizes an electrode
heating.ThesteamhumidierCondairCP3isdesignedforairhumidicationviaasteamdistributor
(steamdistributionpipe,ventilation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 steplessly via the internal or an external continuous controller
orwithanOn/Offcontrolviaanexternalhumidistat.