SDT Sherlog Kit Master SDT270, Technical And User'S Instruction Manual

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File name: MAN.MAS.EN‐‐02X‐‐Sherlog‐Master‐user‐manual‐Eng.docx
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4 SDT270 receiver
4.1 Operating principle of the SDT270
4.1.1 General
Ultrasonic waves are sound waves beyond the range of human hearing (>20 kHz). To be detected, we need to use an
instrument like the SDT270, with the capability to receive ultrasonic frequencies and convert them to corresponding
audible sounds.
Ultrasonic waves travel through gases (air), liquids (water, fuel) and solids (bearing housings) in a very directional
nature; unlike audible sounds which disperse in all directions. Ultrasounds are low energy sound waves, therefore they
are quickly absorbed by the medium through which they travel. Ultrasonic waves are generated by:

Naturally occurring mechanical phenomena (friction of rotating equipment), pressure or vacuum leaks (pneumatic,
gas, steam) or arcing and corona (electrical problems).

Artificially by means of a transmitter (like the SDT 200 mW or the SDT 8 MS ‐ 8 x 125 mW) for tightness testing.
4.1.2 Applying ultrasonic waves on the Sherlog
The SDT270 detects ultrasonic signals, converts them to audible
frequencies, and amplifies them. The challenge is to transpose the
received signal, using the heterodyne technology, into an interpretable
audible signal. This solution extends the ability of the human ear
beyond the simple audible range and into the ultrasonic one.
4.1.3 SDT270 receiver features
The SDT270 receiver provides:

Data storage

Tamper‐proof hatch cover survey routine software with data logging and data transfer to PC.

Transfer software on USB flash drive (1).

Sensor connector for ultrasonic and non‐ ultrasonic external.

Build in tachometer and temperature sensor (2)
(1) Through the connector for PC.
(2) Only active after obtaining the required key from SDT.
4.1.4 Updating possibilities
Regularly and for different reasons, the software version from the SDT270 receiver will be updated, the most common
reason being a technical improvement in the core software.
This makes the SDT270 receiver the only Ultrasonic Multifunctional receiver in the world that is always up to date.
Every owner of a SDT270 receiver can download this software update. The only things needed are a cable, an
Internet connection and an unzip software.
The main function of the SDT270 is converting
high frequency signals into audible.