Preparing for measurements 5  Operation
DMS Go+ Edition 4 (05/2014) 5-23
DUAL
The measurement mode DUAL is available for dual-el-
ement probes. 
The wall thickness is determined on the basis of the ul-
trasonic time of flight from zero up to the last zero cross-
ing before the first flank crossing detected in gate A. The 
ultrasonic time of flight is corrected by the probe delay 
line which is calculated automatically during the zero 
point calibration. 
This measurement mode is suitable for non-coated ma-
terials showing corrosion at the rear, especially with 
curved and irregular backwall or inner wall surfaces.
DUAL-MULTI
The measurement mode DUAL-MULTI is available for 
dual-element probes. 
The wall thickness is determined on the basis of the ul-
trasonic time of flight from the last zero crossing before 
a peak echo is detected in gate
 A and ends with the last 
zero crossing before a peak echo in gate
 B. 
This measurement mode is suitable for coated materials 
with smooth, parallel surfaces.
Only the measurement modes supported by 
the selected probe type are displayed as op
-
tions to choose from. The measurement 
modes TOP-COAT and AUTO-V are only 
available for DMS
 Go+ TC and described in 
detail in chapter 7 of this manual.
The choice of measurement mode must al-
ways be identical for the calibration and the 
subsequent measurements.
– In the function group PROBE&CAL, select the func-
tion TG MODE.
– Select the suitable measurement mode for the con-
nected probe and measurement task. The instrument 
is immediately adjusted.