User Guide
SKPx5.xxxUxElectro‐hydraulicactuators TechnicalInstructions
DocumentNumberCC1N7643us
July25,2017
SiemensAGBuildingTechnologiesDivision Page9
Specifications
Continued
Auxiliary
Proofofclosureswitch Non‐adjustable
features
Settingrangeofauxiliaryswitch 40%to100%ofstroke
Switchrating
4A(2A,cos
=0.3)
NOTE:
AUX‐circuitnotforSELV(safetyextralowvoltage)!
Operation
(seeFigure1)
Safetyshut‐off
function
Theelectro‐hydraulicactuatorconsistsofacylinderfilledwithoil,apistoncontaininganelectric
oscillatingpump,andareliefsystem.Whenpowerissuppliedtotheactuator,thereliefsystemcloses,
andthepumpmovesoilfromthereservoirintothepressurechamber.Thisactioncausesthepistonto
movedownwardinthecylinder,openingthegasvalve.Whenpowertotheactuatorisinterrupted,
thereliefsystemopensandthegasvalveclosesinlessthan0.8seconds.
Apositionindicator,visiblethroughthetransparentwindowoftheterminalboxcover,showsthe
entirepossiblestrokerangeof
theactuator.Alight,whichisvisiblethroughthelowerlefttransparent
windowoftheterminalboxcover,indicateswhentheactuatorreceivespower.Anoptional,non‐
adjustableSPDTproofofclosureovertravelswitchsignalstheclosedpositionafterthegasvalvehas
closed.AnoptionalSPDTauxiliaryswitch
isadjustablebetween40%and100%ofthestroke.The
adjustmentscrewandscalearelocatedontherightsideintheterminalbox,andarevisiblethrough
thetransparentwindowoftheterminalboxcover.
Thesealinggasket,AGA66,canbeinstalledbetweentheactuatorandthegasvalve
toprovideNEMA
3,3R,and4protectionratingforVGG10.xxxU/VGDxx.xxxU/VRD40.xxxUvalves.