Siemens 200 instruction manual TVT Time Varying Threshold curves, Auto False-Echo Suppression

TVT (Time Varying Threshold) curves

A TVT curve describes a threshold below which any echoes will be ignored. The default TVT curve is used, until P837 and P838 are used to create a new ’learned TVT curve’.

Auto False-Echo Suppression

False echoes can be caused by an obstruction in the beam path (pipes, ladders, chains, and such). Such false echoes may rise above the default TVT curve.

P838 allows you to set a distance, and P837 then instructs the MultiRanger to ’learn’ where the obstructions/false echoes are within that distance. The new TVT curve is set above the false echoes, screening them out.

Display before Auto False Echo Suppression

(or when P837 = 0)

default TVT	true
		P839
	echo	Hover Level

(db)
Level	false
	echo

Distance (meters)

Display after Auto False Echo Suppression

TVT curve
	material
(learned)
	level

(db)
Level	false
	echo

Distance (meters)

Appendix B: Tech Reference

7ML19981FB06 MultiRanger 100/200 – INSTRUCTION MANUAL Page 225