Reading dihydrogen monoxide meter (Or water meter in plain speak) - Page 1
Forum section: electronics / projects

author: kolbep
author_rank: Frequent Contributor
timestamp: February 20, 2017, 03:40:05 pm
content: Hi All.I thought the title might get some views.I am looking to read the ticks of this water meter with a Wemos or Arduino,But my Google Powers are at a low today.I believe the pickup port is at the bottom left next to the window, but I am unsure of what type of pickup this meter would need.Is it an IR Tx and Rx LED, or must I somehow put a reed switch in the hole (and do you get front on reed switches)?I have tried shining a light in the hole, but I do not see any changes when the water is flowing.Thanks for the input

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: February 20, 2017, 03:54:58 pm
content: Some meters use a rotating metal vane, picked up with 3 coils. On the ones I've seen, the vane is visible from the front but there may be other variants

author: coppice
author_rank: Super Contributor
timestamp: February 20, 2017, 04:14:45 pm
content: What makes you think the meter has a port for measuring the flow electronically? Most don't, and it can be a PITA trying to adapt them for electronic measurement.

author: johnkenyon
author_rank: Regular Contributor
timestamp: February 20, 2017, 04:45:23 pm
content: I suggest that you positively identify the meter manufacturer and model (5 minutes of Googling suggests you have a LXH-15-20 meter), and see what kind of remote metering facility the meter has built in. IMHO the most sensible way a manufacturer can facilitate remote metering with a dumb meter is to fit a magnet on one of the dials and have it operate a reed switch.That way you can have the insides good for potable water, and the sensor on the outside can be sealed against dirt/water ingress.Here's a couple of links for you:http://www.younio.com/pro_b.asp?bid=21http://www.chinaaimei.com/200646/news_img/2010613171915.pdf/John

author: CatalinaWOW
author_rank: Super Contributor
timestamp: February 20, 2017, 05:13:49 pm
content: Seems to be a Precision Meters meter, unknown model and options.The following suggests that their normal way of providing an output is with a reed switch (magnet would be mounted on the rotating piston) and also suggests a scale factor.http://www.precisionmeters.co.za/volumetric-rotary-piston-meters-15a-20a/While this gives some principals of operation:http://www.precisionmeters.co.za/precision-meters-water-meter-selection-options/With the model data sheet here:http://precisionmeters.co.za/wp-content/uploads/2014/05/PM-ASM-LXHS-15-20mm-Plastic-v3.pdfYou may get lucky and just be able shove a reed switch down into the hole, or slightly less lucky, tape a reed switch to the outside of the meter in the appropriate spot.

author: kolbep
author_rank: Frequent Contributor
timestamp: February 20, 2017, 07:16:32 pm
content: Thanks for those datasheets. It is interesting how those water meters work.Anyway, I just hooked an LED, Resistor, 9v Battery, and a reedswitch from a door alarm together,and dropped it in the hole next to the counter. And when I started drawing water, the LED was flashing at a rate to match the speed of the flow.So I guess it really was that easy, and I should have actually done that before posting.So, very soon I will be able to graph my water consumption (together with Electricity usage that I plan on using the OpenEnergyMonitor type setup.)So many things to do, so little time.....