Am I allowed or is it safe

I am a newby although not new my self - 2 score & 10 + 2 -
As you may have realised from my username I am not in agreement with the spy in the home i.e Smart Metering but am very interested in energy monitoring/conservation. I do have the ‘‘Owl’’ electrical current/energy monitor but would very much like the ability to log/record my energy usage using my desktop.

So before I embark on another project… time on me hands yer see… the overriding question for me is…is it deemed safe too attach sensors to the Domestic Gas Meters ( Area Classification div1, div2, an all that ) yes…in my former life I was in the Oil/Gas Game. I do realise these devices are of low energy, but the ‘‘Meter Man’’ may not think so.

I’ve just come across OEM web site and am looking forward too having a gander whats available…Joe

As far as I know, as long as whatever is not permanently attached, it’s OK.

If you use a reed switch - which is what’s inside the attachment that some meter manufacturers sell - to pick up from a magnet inside the meter then, while it’s not IS (Intrinsically Safe - I once worked for the mining sector), the power source is very limited and the contacts are totally sealed in glass, so no exposed contacts to generate a spark. I’d say it’s far less dangerous than having the gas meter in your garage and plugging in the lawnmower a yard away.


There must have been some feedback from contributors of OEM forum concerning Meter Men’s visits, cos they would be the first to have reason for complain, and as we know just like Parking Ticket Men as well as HSE Men they love to stop the job… a little power goes to their heads. Anyway I will still go ahead with the project cos I have now ordered two IR Tx/Rx sensors.

As you rightly commented there’s more danger from all sorts of sparking electrical equipment lying around such meter’s, have seen it in my daughters old house.

Please guide me… is there, shall we say a ‘‘black box’’ that counts the pulse’s and presents the power readings, that I can buy…joe

I cannot remember seeing any reports of meter readers objecting to switches or Hall effect sensors attached to meters, thought there’s probably one, somewhere, who’ll raise an objection. But as I noted, some meter manufacturers sell the add-on reed switch, and some meters have provision for mounting one.

The nearest we can offer to a magic black box is the emonPi. Basically, that’s a small computer that hosts a web site (for the data display) and has the interfaces necessary to monitor both your electricity and the pulses from a switch attached to your meter. But you might need to do a bit more and build your own interface to use IR optics - it depends on exactly what you’re getting.

But have you tested for a magnet? I’d first try holding a magnetic compass close to the fastest register wheel. If it swings as a certain number goes past, it means there’s a magnet inside the wheel and you can use that and simply use a small reed switch to sense the magnet. That’s a far simpler method than looking for the reflective patch on the register through the glass, and will interface directly with the emonPi.