Example of setting of port No 1 (index=0) mode to ”1” option with involved equalizing filter (slow pulses):
cfg#dmode1 1
Mode[1] = 1 - slow
cfg#
Detailed description of
”
Leak” alarm function can be found in the paragraph
below. Detailed description of
”
Burst” alarm function can be found in the paragraph
below. Detailed description of sensor input settings can
be found in the paragraph
”
Setting of sensor inputs” below. Detailed description of
”
tariff switching” function
can be found in the paragraph
below.
3.1.7
Description and setting of
”
Leak” alarm function
”
Leak” function is used for detection of such situations in the consumption of gas, water or other liquids, when
there are permanent low-quantity losses caused by minor leaks in the distribution system. In view of the fact that
remote reading systems don’t record consumption continuously but in some steps (usually given by full turn of its
measuring disk), it could take quite long time until the trouble is discovered.
”
Leak” function is based on the common pattern that during the normal long-term (e.g. day, week) operation there
are usually some regular time intervals, when the consumption is in its
”
idle” status, because the gas/liquid is not
consumed from natural reasons (e.g. during the night, or out of working hours). In these idle time intervals the
consumption should be zero volume. If there are any leaks, time intervals with zero consumption practically either
do not occur, or there are only short intervals caused by discontinuity of measuring system (e.g. if one metering
pulse represents 100 litres, minor leak could become evident even after several hours, when such quantity will leak).
.
”
Leak” function principle is shown in the figure
. When setting of
”
Leak” alarm function the length of detection
period must be entered by setting of
”
Leak Detection Period”
parameter. After expiration of this period the
system evaluates whether during this period at least one time occurred the situation, when the consumption was
in zero level during preset time interval (entered by
”
Zero Period”
parameter). If there is no leakage, it is highly
probable that zero consumption period occur at least once during the period and system evaluates the period as
”
no alarm” status (see upper part of the figure
). But if there is no one interval with zero consumption registered
during whole detection period, module transmits to superior system
”
Leak” alarm message (see lower part of the
figure
”
Leak” function can be activated for chosen port by using of
”leakp[index]”
command that defines the length of
detection period (
”
Leak detection period”
parameter) in hours. By using of
”leakz[index]”
command setup
concurrently for the same port the length of zero consumption interval (
”
Zero period” parameter)
in minutes.
If one of these parameters is set to ”0” for some port,
”
Leak” function is deactivated for that port.
Figure 4:
”
Leak” alarm function principle
WB169-SI2
15