Meter and method for detecton of a meter having been tampered with

A method according to any preceding claim, wherein the fraud condition comprises a first fraud sub-condition and a second fraud sub-condition, the first fraud sub-condition comprising that air is present in the flow measurement portion for both the first period of time or more and the or a second period of time or more, the second fraud sub-condition comprising that air is present in the flow measurement portion for the first period of time or more and that a pressure in the flow measurement portion is below a given pressure.

A method according to any preceding claim, wherein the method comprises measuring a pressure in the flow measurement portion and wherein the fraud condition further comprises that the pressure in the flow measurement portion is below the or a given pressure.

A method according to any preceding claim, wherein the method comprises evaluating an in-operation condition, wherein the in-operation condition is indicative of the meter being operational, and wherein evaluation of the fraud condition is carried out in response to the in-operation condition being evaluated as met.

A method according to any preceding claim, wherein the first period of time for which air is present, the or a second period of time for which air is present, and/or the or a given pressure is adjusted dynamically, for example, in response to conditions of a water mains network.

A utility meter having a processor for detecting that the meter has been tampered with, wherein the meter comprises a flow measurement portion, a flow sensor for measuring water flow in the flow measurement portion, an air detector for detecting a presence of air in the flow measurement portion, and wherein the processor is arranged to:

• evaluate a fraud condition, wherein the fraud condition comprises that air is present in the flow measurement portion for a first period of time or more;
• and
• generate an alert in response to the fraud condition being evaluated as met.