9
9
Figure 7
Figure 6
- Blank Adjust @ 4
envelope. This feature has helped “clean” up the screen for easier interpretation.
When blanking is set to TRACK, the leading edge is the reference point for the blank
function. This allows the waveform to move horizontally on the screen (due to variation in
velocity or transducer spacing) while still maintaining the blank function
relative
to the leading
edge of the waveform. When blanking is set to STAY, the blanking will stay at the last
TRACKed position. If the echo moves to the right on the screen (further in time) it will
disappear into the BLANKed zone. The BLANKing and TRACKing take on fixed properties of
the BLANK while it was last in the TRACK mode.
BLNKADJ
Blank Adjust
is used to adjust the width of the first signal
accepted before blocking the rest. The number shown is
based on the pulse ENERGY. A number of 2.0, for
example, sets a width two times the time of the pulse.
Selections include:
GAIN
Gain is available from the front panel. This function is used
to adjust the amplitude of the A-trace display. Increasing or Decreasing the GAIN will cause the
A-trace signal to increase or decrease in amplitude.
RANGE
Range is available from the front panel, This function is used to determine how much time
(distance) is represented on the horizontal axis of the A-trace display. Increasing or Decreasing
the RANGE will cause the A-trace display to expand or contract.
DELAY
Used to adjust the start of the A-trace display along the horizontal axis. Gates that are
synchronized with the A-trace will also delay accordingly.
GATE
MEASUREMENT GATE is used to select the type of
inspection to be performed.
C
AMPLITUDE mode enables the use of the flaw
amplitude gate and alarm(as seen in Fig 3). Note that
ALARM follows GATE on the menu in this mode.
C
DISTANCE gate enables the distance measurement
gate and calibration settings as seen in Fig 6. Note that
VELocity and ZERO follow DIST. Setting of GATE.
IF IN AMPLITUDE MODE (refer to Fig 7)
ALARM POLARITY
C
OFF: ALARM enables or disables the FLAW gate alarm.
C
POSitive alarm means alarm activates when the signal exceeds threshold in gate.
C
NEGative alarm means alarm activates when signal drops below gate threshold
START
GATE START allows adjustment of the horizontal position of the leading edge (start) of the gate.
Continuously adjustable from 0.000 to 200.0 inches (500mm).
WIDTH
GATE WIDTH allows adjustment of the horizontal position of the trailing edge (width) of the gate.
Continuously adjustable from 0.000 to 200.0 inches (500mm).
