GB2447903A

GB2447903A - Water leak alarm for premises using acoustic signal sent from water meter

Info

Publication number: GB2447903A
Application number: GB0705793A
Authority: GB
Inventors: Douglas Gray
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-03-27
Filing date: 2007-03-27
Publication date: 2008-10-01
Also published as: GB0705793D0

Abstract

The automatic water leak detection system for a metered premises comprises a remote monitoring unit F installed next to a water meter and an alarm unit ( E fig 2) installed in the premises. A detector on the meter D sends a pulse to the monitor when the meter needle rotates thus indicating water flow. The monitoring unit determines if the detected water flow is normal or abnormal. Only if the flow is normal does the monitoring unit periodically transmits sonic signals down the water pipe C via the sonic transmitter E. The alarm unit in the premises listens for the periodic signal with receiver (A fig 2) and if no signal is detected an audible and/or visible alarm is triggered. The monitoring unit may be powered by disposable battery or a rechargeable battery, which may be charged via generator G in the pipe C.

Description

AUTOMATIC WATER LEAK DETECTION SYSTEM

This invention relates to an automatic water leak detection system.

All water utility companies are installing, or have installed, water meters for all users of water. In some instances water meters are remotely located from the premises using the water, especially for domestic users in rural areas. Therefore, if a water leak occurred between the remote water meter and the premises using the water, it could go undetected causing significant amounts of water to be lost.

As the water meter cannot differentiate between water used by the premises and water lost though the leak, the consumer will in most cases need to pay for the water that has been lost. Dependent on the nature of the water leak the cost to the user for slow leaks over a long period of time and large leaks for a relatively short period of time could be significant.

In order to detect water leakage between a remote water meter and the premises where the water is used requires a device to be fitted at the remote water meter, which can monitor water flow and signal abnonnal water flow conditions, typically back to the premises where the water is used, when they occur. Although automatic water leak detection systems are available they are mainly designed for installation in the premises where the water is used and do not utilise remote water meter monitoring devices.

In rural environments remote water meters are usually installed in the ground adjacent to a road and bordermg the property to be served. Access to the water meter for reading the meter and turning offlon the supply is usually via a small metal cover.

Because of the location of the remote water meter no electrical power is available and because of the exposed nature of the location it is impractical to utilise solar power, wind power or lay cables to provide electrical supplies. The use of either radio transmitters or cables for remote signalling is also impractical.

The automatic water leak detection system herein described solves these problems by generating electricity and performing remote signalling within the remote water meter installation.

The automatic water leak detection system comprises a remote monitoring unit and an alarm unit. The remote monitoring unit is installed next to the remote water meter and the alarm unit is installed in the premises where the water is used.

An abnormal water flow condition is detected by the remote monitoring unit when the water flow through the water meter exceeds a predetermined level, referred to as X

for the purpose of this description.

An abnormal water flow condition is also detected by the remote monitoring unit when the water flow through the water meter does not drop to a predetermined level, referred to as Y for the purpose of this description, within a specified elapsed time period known as Z for the purpose of this description.

The predetermined levels for X, Y and Z are set in the remote monitoring unit at time of installation to specifically match the water flow characteristics of the premises being supplied with water.

This method of water flow monitoring best represents the sporadic nature of water used by a domestic user. For example, water flow is at a maximum when baths are being filled, toilets flushed, washing machines and dishwashers are in use and water flow is at a minimum when water taps are all off and appliances are not being used.

A detailed description of the automatic water leak detection system invention is hereby provided using reference to the drawings in figure 1 and figure 2 of page If 1.

Figure 1 shows a water meter with the mains water input pipe A, a stopcock B and the metered water supply output pipe C. A water flow detector D is attached the analogue flow meter of the water meter in such a way that it provides an electronic pulse for each revolution of the water flow analogue meter needle, for example, by a magnetic reed relay contact closure activated by a magnet on the analogue meter needle (standard facility on most water meters).

The electronic pulsed output from the water flow detector D is detected by the remote monitoring unit F to determine, by electronic means, if water flow is normal or abnormal. During normal water flow conditions the remote monitoring unit F periodically transmits sonic signals down the metered water pipe C via the sonic transmitter E. During abnormal water flow conditions the remote monitoring unit F stops transmitting periodic sonic signals down the metered water pipe C. Figure 2 of page 1/1 shows the water input pipe A and stopcock C controlling the water into a premises via water pipe B. A sonic signal detector D is connected to water pipe A in such a way that sonic signals present in the water pipe are detected and fed to the alarm unit E for electronic processing.

The alarm unit E continuously detects if the periodic sonic signals are present and if for some reason detection of the periodic sonic signals cease an alarm is initiated, for example, an audible and/or visible alarm as appropriate.

The characteristics of the sonic signals are chosen such that they can be electronically detected by the alarm unit E with minimum interference and disruption from sporadic sonic signals ever present in water pipes cause by vibrations from number of natural and man made sources.

Electrical power for the remote monitoring unit F can be from either a disposable or rechargeable battery or as shown in Figure 1 of Page 1/1 from an electricity generator G, which uses the sporadic water flow through the water pipe C to generate electricity which in turn recharges a rechargeable battery located in the remote monitoring unit F. As the electrical energy required by the remote monitoring unit F is very low the electricity generator G only needs to generate a small amount of power thereby causing negligible water flow disturbance or drop in water pressure.

The detailed description of the automatic water leak detection system invention herein provided relates to a field installed system to a normal remote water meter installation. The same automatic water leak detection system description also applies to new water meters that could be designed to include part or all the components needed for the same method of automatic water leak detection and/or electricity generation herein described.

Claims

1. The automatic water leak detection system comprising a remote monitoring unit installed next to a remote water meter and an alarm unit installed in the premises where the water is used provides automatic water pipe leak detection.

2. The automatic water leak detection system, as claimed in Claim 1, comprising a remote monitoring unit, a water flow pulse generator and a sonic transmitter are used to transmit sonic signals into a water pipe.

3. The automatic water leak detection system, as claimed in Claim 1 and Claim 2, comprising a remote monitoring unit, a water flow pulse generator and a sonic transmitter, transmit sonic signals into a water pipe only when water flow through a remote water meter is normal.

4. The automatic water leak detection system, as claimed in Claim 1, comprising an alarm unit and a sonic signal detector are used to detect the presence of sonic signals in a water pipe.

5. The automatic water leak detection system, as claimed in Claim 1 and Claim 4, comprising an alarm unit and a sonic signal detector are used to provide an alarm when sonic signals are not detected in a water pipe.

6. The automatic water leak detection system, as claimed in Claim 1 and Claim 2 and Claim 3, comprises an electricity generator powered by water flowing through the water pipe is used to charge a rechargeable battery to provide constant electrical power to a remote monitoring unit, a water flow pulse generator and a sonic transmitter.

7. The automatic water leak detection system, as claimed in Claim 2 and Claim 6, can be provided for existing installations or manufactured as part of a remote water meter to be used for new or replacement installations.