#Gas meeter install#

Paul Allen ( MarsFlyer) has successfully used a Melexis MLX90248 hall effect sensor. Low power consumption enables use with a battery powered emonTx or JeeNode. Since a gas meter will not usually have a mains power connection located nearby, it's desirable for a Hall effect sensor to be a low-power device. The hall effect sensor can be located on the underside of the cut-out section, pointing upwards, or attached directly to the dial face. The magnetic point is visible as a small silver oval on the rightmost digit. The image below shows an Actaris gas meter, suitable for monitoring via this method. A microcontroller with a Hall effect sensor attached to an interrupt line, can count each complete disk rotation. Sensor output is a voltage which varies in response to a magnetic field. Hall effect sensors can detect a magnetic field.

A uniquely coloured numeral that can be detected by an infra-red reflective sensor.

A reflective spot on the dial that can be read by an infra-red reflective sensor.

A Hall effect sensor or a reed switch can detect disk rotation. Whilst most meters don't have that capability, many gas meters have a unique 'spot' on their rotating disk which can be read with a suitable pickup and electronics. The method used counts the revolutions of a dial to determine the volume of gas consumed. rules, you can be certain that every precaution has been taken to Required for every wire that is not earthed that enters the hazardous area. barrier in a domestic setting, but if you do,Įither for peace of mind or because you think it is necessary, then note that a barrier is

#Gas meeter install#

It should not be necessary to install an I.S. Only 0.02 mJ (that’s the energy stored in a 400 nFĬapacitor charged to 10 V), is required to ignite hydrogen. There must also be no significant energy storage device, a capacitor or inductor, on the The resistor limits the current to a safe value. The Zener diodes, normally inactive, are there to blow the fuse should the input voltage Will be a long way below even the hydrogen line. Supplied to homes is composed predominantly of methane, but hydrogen is the mostįrom this, it is clear that, generally, the voltages and currents required by a pulse monitor The actual values depend on the gas in question.

Known as “Intrinsic Safety”, which specifies the voltages and currents below which ignition The case of hydrogen - can normally be met without difficulty by proper device ratings andĬircuit protection, and prevention of ignition by a spark is achievable with the practice No heat source that reaches a high enough temperature, and any spark that might occurĭoes not have sufficient energy, to ignite the gas. Notwithstanding that, escaping gas could be ignited by a spark, so to completely removeĪny danger, it is imperative that should a fault occur in the monitoring equipment, there is SafetyĪs far as can be ascertained, the only rule (in the UK, other countries’ standards may vary)įor electricity and gas installations is that the gas meter should be separated by more thanġ50 mm from the electricity meter, consumer unit or any switch or socket outlet. If you are very lucky, your gas meter has a connector that provides access to the meters pulse output, enabling you to determine gas consumption via pulse counting, see introduction-to-pulse-counting. This page pulls together information on DIY gas meter monitoring using pulse counting methods.