The principle of stationary noise logging

The period how long water flows out of a point of damage has a significant influence on the total loss created by water leaks in supply networks. A reduction of water losses accordingly demands a meaningful decrease of leaking times.
In addition to conventional methods of detecting leaks systematically in grown network structures the installation of stationary noise loggers SePem® 01 marks a useful alternative to monitor sections of the system permanently which have once proven to be free of leaks.
For this reason the SePem® 01 loggers are placed at valves. Of course it is also possible to connect them to underground fire hydrants. The instruments do record noises in a defined period of measurement and additionally transmit radio signals during a certain time schedule out of the valve boxes. For reception of those radio signals the SePem® 01 - Master is applied, which collects data when driving along the measurement locations. It is not necessary to take out the loggers from their places or to open the valve boxes therefore.
Such data package contains the most essential information about the passed measurement cycle. The most significant information in this regard is the minimum noise level.
If now the SePem® 01 loggers are read out repeatedly in a suitable and systematic scheme the corresponding minimum levels can be compared at each location. As long as there will be no leak, the readings will not change. But if a leak occurs, the recorded minimum noise level will increase immediately and will remain high afterwards. Depending on the scheme of repetition of driving along the measurement locations (e. g. once per week) the runtime of the leak will be limited to this short period of time and the loss will be recognised not only with the next systematic survey - in worst case after some years.

Programming options

The communication instrument SePem® 01 - Master allows even the less experienced operator to receive quick and reliable results due to the easy and intuitive menu structure as well as the implementation of a jog dial.

With the SePem® 01 - Master the SePem® 01 loggers can be programmed and the data can be read out. Three different measuring options are available, which can be chosen with or without graphical analysis.
The standard consists in an endless measuring process where measurements are taken in a certain interval free to be programmed. Before read out of data with the SePem® 01 - Master, the logger evaluates a minimum noise level.
The second option is to take a time controlled measurement, e. g. for 30 minutes from 2:00 to 2:30 o'clock during the night, and this will be repeated every 24 hours.
The third possibility is one single measurement that can be taken any time and could be of any duration.
Additionally an online measurement can be carried out prior to installing the logger, in order to decide, if the chosen place makes a suitable measurement location.
In case of an indication of a leak during reading the results, a full download of all values is possible - directly on site.

Technical data

SePem® 01 - Master

Innovative handling concept by jog dial and soft keys as well as intuitive menu guidance
Flexible carrying concept
Supporting handle
4 MB internal memory
Power supply by 4 rechargeable or disposable batteries „Mignon"
Operation from the 12 V supply of the car by direct cable link
Operating time min. 8 hours when rechargeable batteries are selected
Protection according to IP 54
Operating temperature:-10 °C ... +50 °C
Storage temperature:-20 °C ... +70 °C
Weight approx. 1,000 g
Dimensions (W x D x H) in mm: 148 x 57 x 205 (253 with handle)

SePem® 01

Robust aluminium die-casting housing with refined surface
Horizontal or vertical installation by 2 magnet connections M10
By threaded slide in horizontal installation also applicable in valves boxes with eccentric valves
Bi-directional data radio 433 MHz with 1/10 mW
Errors automatically corrected, digital high-performance radio transmission
Power supply by built-in Lithium battery
Operating time: typically 5 years, with daily radio stand by
(with radio transmission once per week significantly longer)
Protection according to IP68
Dimensions (W x D x H) in mm:108 x 51 x 50
Installation depth horizontal in mm:67
Installation depth vertical in mm:125