Epson USN 52L MTL VEL Sound velocity, Zero Probe delay, Adjustment of the freely selected value

Adjustment of the USN 52 R Operation

MTL VEL Sound velocity

In MTL VEL you set the value for the sound velocity in the material under test. You can change between preset fixed values or continuously adjust the value.

Operation:

–Set the sound velocity in MTL VEL with M, e.g. 5920 m/s (longitudinal wave velocity in steel).

HNote:

The default value for the sound velocity can be changed in the second operating level (functions VE- LOCITY # 1 and VELOCITY # 2) if you frequently oper- ate with other materials (refer to Chapter 5.6).

Adjustment of the freely selected value:

–Simultaneously press NO in MTL VEL.

–Change the setting with M.

With free adjustment of the value, the function name appears in small letters (mtl vel). In this way you are able to recognize which mode of adjustment you have selected.

AAttention:

Always make sure that the sound velocity in MTL VEL is set correctly! The instrument calculates all interval and distance indications using the values which have been set here.

ZERO Probe delay

Each probe has a delay block (protective layer, delay wedge with angle-beam probes) between the element and the coupling surface. The initial pulse must be transmitted through this delay block before the sound can enter the test object. The ZERO function allows you to take into account the loss of time caused by the delay block in order to achieve the correct measure- ment of all sound paths in the test object.

Operation:

Set the value for the probe delay in ZERO using M.

HNote:

If the value for ZERO is not known, read Chapter 5.3 beforehand in order to determine this value.

Krautkramer USN 52R/USN 52L Issue 05, 02/00 5-13