TDS-100M Manual
23
800
1200 975
920
880
5
24×30
32
900
1300
1075
1020
980
5
24×30
34
1000
1400
1175
1120
1080
5
28×30
36
§4.8 check installation of transducers
After the completion of transducer installation, the user should check the following items to see
whether the installation is suitable,whether the received ultrasonic signal is correct,enough
strong,that could make the meter work normaly and long time running. By checking the receiving
signal strength S, the signal quality Q value, the delta time, , the transit time ratio
R to assure whether the installation point is good or not. Normaly,apply couplant on the
transducers and attach them on the pipe ,so can obtain measurement results,but it is better to
chech followings to ensure the flow meter is working properly and the results are reliable and
accurate.
§4.8.1 Signal Strength
Signal strength S (display on M90) indicates strength of sending and receiving signals from
upstream transducer and downstream transducer by a 3-digit number. [00.0] means there
is no signal detected, and [99.9] refers to the maximum signal strength that can be detected.
When installation,do best to adjust the position of transducers and check whether the couplant is
sufficient,to make sure to gain the strongest signal.Although the instrument works well
when the signal strength ranges from 60 to 99,when the signal strength is too
low,you should chech the installation position ,installation space,whether the pipe is suitable to
install or change to install by Z method. stronger signal strength should be pursued, because a
stronger signal means a stable measurement results,long and reliable running..
§4.8.2 Signal quality(Q value)
:Signal quality is indicated as the Q value(display on M90) that represent the receiving signal
is good or not,TDS-100M series use 00-99 digits to represent signal quality.00 represent the worst
signal,99 represent the best signal,normaly the signal quality should be above 60. the reason of
poor signal quality could be big interference,or worse installation of transducers,or using bad
quality,not professional signal cable.normaly ,to adjust transducers repeatly,check the couplant
that is enough or not,until the signal is better.
§4.8.3 Total transit time,delta time
The total transit times (or traveling time) and delta time are displayed on menu window M93,they
can display whether the installation is suitable or not, They are
the basic two parameters for the flow meter’s internal measurement and calculation,. When the
data of delta time fluctuates too much,the showed flow rate and velocity will change quickly,under
such condition,it means the signal quality is not good,perhaps the conditions of pipe is not
good,not suitable installation of the transducers,or wrong parameters input.normaly the fluctuation
of delta time is less than ±20
％
.but when the pipe diameter is too small or lower flow velocity,the
fluctuation of delta time
may be higher.
§4.8.4 Transit time ratio
:Transit-time ratio (visit on M91)is usually used to check whether the transducer installation
space is good .If the pipe parameters are correct and the transducers are installed
properly, the transit time ratio should be in the range of 100±3 %.when the
ratio is over the range,you should check,
a) If the entered pipe parameters are correct?
b) If the actual space of the transducers is the same as or close to what shown on window
M25.
c) If the transducers are installed properly in the same axis plane of pipe?
d) If the mounting location is good, if the pipe has changed shape, or if the pipe is too old (i.e.,
