Kamstrup ULTRAFLOW 54 DN150-250, Техническое описание, Страница: 40 / 64

TECHNICAL DESCRIPTION ULTRAFLOW
®
54 DN150-250
5512-876 GB/04-2012/Rev. F1
40
The excess quantity of water in connection with start is the water volume that passes through the sensor during
the time
1 b
t before the first accumulation
1
V within the test period. In the same way the lacking quantity is the
water volume passing through the sensor during the time
1 e
t from the last accumulation
n
V until stop.
The volume accumulated during the test can be stated as:
2 1
1
2
2 1
2 1
...
e e
e n
n
b b
b
t t
t V
V V
t t
t V
+
×
+ + +
+
×
∑
8.15 Calibration procedure using serial data and externally controlled start/stop
The routine for calibrating ULTRAFLOW
®
54 using serial data is outlined below.
Figure 22
The sensor must be in test mode (see paragraph 8.13 ). Calibration is started by grounding pin 4 of the internal
connector (see Figure 22) and at the same time starting the test. This might e.g. take place at the same time as the
master meter is started or the diverter of the weight is changed. Now ULTRAFLOW
®
accumulates water volume until
pin 4 is disconnected to terminate the test. Subsequently, the volume accumulated during the test can be read in
consideration of start and stop. From the test has been completed and until the accumulated quantity of water can
be read, min. 2 sec. must pass (T
read
). Communication with ULTRAFLOW
®
during test is not allowed.
Pulse emission stops when pin 4 is disconnected. The read water quantity and the number of emitted pulses may
differ as the pulse emission is monitored in intervals of 1 second.