em-tec SonoTT, Operating Instructions Manual

Page: 18 / 52

EN
7 Adjustment and Calibration of the SonoTT
TM
Clamp-On Transducer
As the function of the SonoTT
TM
Clamp-On Transducer is based on an acoustic measurement principle,
parameters such as the tubing size and material, or the medium as well as its temperature can impact the
ultrasonic signal and thus the transit time difference between them. To take these factors into account and
to ensure the highest possible accuracy regarding the measured values, each sensor is individually adjusted
and calibrated prior to shipment.
The relevant parameters for the adjustment and calibration are:
– tubing material
– medium
– medium temperature
– flow range
7.1 Adjustment
An act of modifying something, in this case to fit a certain standard, the sensor adjustment represents an
actual intervention in the measurement system. To ensure that the parameters stated above are factored
into the measurement and consequently into the flow values displayed by the SonoTT
TM
Ultrasonic
FlowComputer, parameters such as the amplitude of the ultrasonic signal or the length of the ultrasonic burst
are changed to fit the tubing and the medium used during the application.
.
As a result, the adjustment is an action that permantently alters the
device as the setting of the burst signal (scan window and amplitude)
and the sequential balance line are changed.
Since these parameters have a deep impact on the sensor‘s
performance, and since adjusting the sensor represents an intervention
of the measurement system, adjustments may only be carried out by
em-tec GmbH.
7.2 Calibration
The term ‘calibration‘, on the other hand, refers to the act of checking the accuracy of a measurement device
by comparing its measurement values with those of a device with a known accuracy. This comparison is
subject to a specified measurement setup and specified measurement conditions. During the calibration
process, neither the devices involved nor any of their parameters may be changed, manipulated, or altered
in any way.
Ideally, the SonoTT
TM
Clamp-On Transducers should be re-calibrated every 24 months. This can be carried out
by the customer on-site or by em-tec GmbH.
For more information regarding this process, please contact em-tec GmbH:
Figure 5: Ultrasonic Signal
SonoTT
TM
Clamp-On Transducer
Page 18 D162-700 SonoTT
TM
Clamp-On Transducer - Operating Instructions V3.0 Copyright em-tec GmbH