Olympus EPOCH 650, User Manual

Page: 121 / 362

DMTA-10055-01EN, Rev. A, February 2015
Adjusting the Pulser/Receiver 109
5.4.3 Damping
The damping control allows you to optimize the waveform shape for high resolution
measurements using an internal resistive circuit. There are four damping settings on
the EPOCH 650 ultrasonic flaw detector:
50 Ω , 100 Ω , 200 Ω , or 400 Ω .
To adjust the Damping

Choose Pulser > Damp , and then vary the setting.
Generally, the lowest resistance ( Ω ) setting increases the system damping and
improves near-surface resolution, while the highest resistance setting decreases
system damping and improves the instrument penetration power.
Selecting the correct damping setting fine-tunes the EPOCH 650 in order to operate
with a particular transducer selection. Depending on the transducer being used, the
various damping settings either improve near-surface resolution or improve the
instrument’s penetration power.
5.4.4 Test Mode
The EPOCH 650 ultrasonic flaw detector can operate in three test modes that you can
select using the
Pulser > Mode parameter:
• P/E
Used to select pulse-echo mode, where a single element transducer sends and
receives the ultrasonic signal. Use either transducer connector.
• Dual
Used to select pitch-and-catch mode, where a dual-element transducer has one
element that transmits the ultrasonic signal and another element that receives the
signal. Use the
T
/
R
labeled transducer connection as the transmit connector.
• Thru
Used to select the through transmission mode, where two separate transducers
are typically located on opposite sides of the test specimen. One transducer
transmits the ultrasonic signal, the other receives. Use the
T
/
R
labeled transducer
connection as the transmit connector.