MC-Basic:pls.PLSPropagationDelay

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It is new property that will be added after 4.5.31 fw version. The delay will express the time between the moment of sending the position command to the drive until it is set as a command value of the drive's position loop. It will be expressed in milliseconds in double floating point format and will be assigned by the user. It's default value will be 8.0 means 2 motion-bus samples of 4ms. Typically used for the delay time calculation. In case 1000*PLSPropagationDelay/Ser.Cycletime > PositionErrorDelay an error will be returned.

DANGER.svgDANGER
Using PLSPropagationDelay discards the old automatic use of PositionErrorDelay property. It is user's responsibility to adjust the PLSPropagationDelay value in the newest FW versions. The value depends on the type of the motion bus and the devices used (drives, remote IOs, ...).

This means in case, PLS position falls between these two samples:t=0 p = p0 v = v0 a = a0 and:

t = T p = pT v = vT a = aT

means p0 < PLSpos < pT, the PLS output will be switched at (relevant to fw versions until 4.7.3):

t = (PLSPropagationDelay - T)*1000 + Δt

From fw version 4.7.3 and above , it will be switch at:

t = PLSPropagationDelay *1000 + Δt

where:

p – positionv – velocity a – acceleration T – duration of one motion-bus in milliseconds.

Δt the inter-sample delay, time when the position passes PLSpos value measured from t=0.


NOTE-Info.svgNOTE
As the PLSPropagationDelay values are given in milliseconds it will be a user responsibility to change it after each change of the sercos.cyceltime. Value will be in double-floating point format internally always rounded up to microsecond value (i.e. 2.5001 same as 2.5).

Short form

none

Syntax

<pls>.PLSPropagationDelay = <double>

Availability

4.7.1

Type

double

Range

0 - MAXD

Units

ms

Default

0

Scope

Task, Terminal

See Also

PLS Timing Issues