### MVD – Motorized valve drive

Block SymbolLicensing group: STANDARD

Function Description
The MVD block simulates a servo valve. The UP (DN) input is a binary command for opening (closing) the valve at a constant speed $1∕\mathtt{\text{tv}}$, where tv is a parameter of the block. The opening (closing) continues for $\mathtt{\text{UP}}=\mathtt{\text{on}}$ ($\mathtt{\text{DN}}=\mathtt{\text{on}}$) until the full open $\mathtt{\text{y}}=\mathtt{\text{hilim}}$ (full closed $\mathtt{\text{y}}=\mathtt{\text{lolim}}$) position is reached. The full open (full closed) position is signalized by the end switch HS (LS). The initial position at start-up is $\mathtt{\text{y}}=\mathtt{\text{y0}}$. If $\mathtt{\text{UP}}=\mathtt{\text{DN}}=\mathtt{\text{on}}$ or $\mathtt{\text{UP}}=\mathtt{\text{DN}}=\mathtt{\text{off}}$, then the position of the valve remains unchanged (neither opening nor closing).

Inputs

 UP Open Bool DN Close Bool

Outputs

 y Valve position Double (F64) HS Upper end switch Bool LS Lower end switch Bool

Parameters

 y0 Initial valve position  $\odot$0.0 Double (F64) tv Time required for transition between $\mathtt{\text{y}}=0$ and $\mathtt{\text{y}}=1$ [s]  $\odot$10.0 Double (F64) hilim Upper limit position (open)  $\odot$1.0 Double (F64) lolim Lower limit position (closed)  $\odot$0.0 Double (F64)

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