A device, method and system for monitoring a network of fluid-carrying conduits

A method according to any preceding claim and comprising the step of the processing means processing the stream of sampled data to extract summary information therefrom.

A method according to any preceding claim, wherein the statistical subset comprised in each data set of the subsampled stream comprises the maximum and/or minimum and/or mean and/or standard deviation and/or another statistical value of the data over the respective period of the data set.

A method according to any preceding claim and comprising the step of, upon receiving a request for a more complete representation of the stream of sampled data at or over a specified time, to transmit one or more of the data sets corresponding to the specified time.

A method according to any preceding claim, where there is a plurality of subsampled streams, each comprising a plurality of data sets that comprise a statistical subset of the stream of sampled data, the data sets of each subsampled stream comprising a statistical subset over periods of different respective length.

A method according to any preceding claim, wherein the or each subsampled stream is stored in a circular buffer.

A method according to any preceding claim wherein the device has plural channels of sensed data and the method comprises the device receiving respective data substantially continuously from each of a plurality of sensors indicative of a respective variable sensed by each sensor;

• the sampling means sampling the data to produce a respective stream of sampled data for each of the variables sensed, the method such that each stream is handled in parallel in substantially the same way.

A device according to claim 28, wherein the device is be modular, components of the device being house in respective housings that can be locally, and optionally releasably, coupled together for operation.

Central control and processing means arranged to receive information from each of a plurality of devices according to any preceding claim in response to a request from the central control and processing means.

A method of analyzing fluid flow in a network of conduits comprising receiving at a central control and processing means information from each of a plurality of devices arranged to measure fluid flow in a conduit of the network, the information from each device indicative of a transient event and comprising a substantially accurate time stamp of the occurrence of that event.

Central control and processing means for identifying the approximate location of the causes of transient events in a network of conduits through which fluid flows, the central control control and processing means comprising processing means arranged to determine based on information from each of a plurality of devices arranged to measure a parameter indicative of fluid flow in a conduit, and knowledge of the geographical position of each device, the approximate location of the cause of the transient event.