# Readings off **URL:** \ **Category:** emonTH\ **Created:** [5 April 2022 21:14 UTC](https://community.openenergymonitor.org/t/readings-off/20176 "2022-04-05T21:14:10Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![NotVeryOriginal](https://community.openenergymonitor.org/letter_avatar_proxy/v4/letter/n/c4cdca/32.png) [@NotVeryOriginal](https://community.openenergymonitor.org/u/NotVeryOriginal)\ **Post date:** [5 April 2022 21:14 UTC](https://community.openenergymonitor.org/t/readings-off/20176/1 "2022-04-05T21:14:10Z")
Hi, I have two emonTHs running, one with an optical sensor for reading electricity led pulses and the other which reads a reed sensor for gas. I’ve left both running for an extended period of time and I have had to periodically adjust them both however given that I have had to do this I am concerned about the historic data and wanting to fix this so that this doesn’t happen again. For both monitors I have created virtual feeds which should represent the meter’s current display, it is the offset that I have had to to keep adjusting to bring the live figure back into line. How best can I go about identifying and rectifying the cause? I believe the gas meter reading with the reed sensor is due to switch bounce but I’m not sure what would be causing the electric meter reading. The meters I have are as follows: - Llandis+Gyr E110 - Estler BK-G4M Below I have attached how I calculate the inputs/outputs. Any advice would be greatly appreciated as I’m currently being over charged by £60 by my current electricity supplier due to a mistake made by the meter reading person so would like to not have any future concerns about the readings reported by Emoncms. **Electric** Pulse input calculation: ![image](https://community.openenergymonitor.org/uploads/default/original/3X/f/d/fd41ece9b937fde3460cad3c7f80a482f0a24b9e.png) Virtual reading: ![image](https://community.openenergymonitor.org/uploads/default/original/3X/f/5/f578b8e1e92d1d5f66cfabd9b2e1b381c94c91c0.png) **Gas** Pulse input calculation:: ![image](https://community.openenergymonitor.org/uploads/default/original/3X/f/a/fa917ad11f232292537ae83dc7047ca931040331.png) Virtual reading: ![image](https://community.openenergymonitor.org/uploads/default/original/3X/1/6/162f63ea8e06aead786ac6c92129c2a40e38987d.png) Thanks in advance. ---
**Author:** ![Robert.Wall](https://community.openenergymonitor.org/user_avatar/community.openenergymonitor.org/robert.wall/32/38246_2.png) [@Robert.Wall](https://community.openenergymonitor.org/u/Robert.Wall)\ **Post date:** [5 April 2022 22:54 UTC](https://community.openenergymonitor.org/t/readings-off/20176/2 "2022-04-05T22:54:37Z")
I had a magnetic reed switch connected to an emonTH for my gas meter, that counted approximately 2.5 per pulse. The addition of a 0.1 µF capacitor across the reed switch completely eliminated the problem. I suggested adding a note about this to the Wiki in January - it’s not happened. I also have an optical pulse sensor, but that’s connected to an emonPi; so not directly relevant. That has on occasions picked up a nearby fluorescent lamp (with a thermal starter) being switched on or off. Others have found light getting to the sensor has been counted (perhaps obvious in hindsight). ---
**Author:** ![Gwil](https://community.openenergymonitor.org/user_avatar/community.openenergymonitor.org/gwil/32/29028_2.png) [@Gwil](https://community.openenergymonitor.org/u/Gwil)\ **Post date:** [7 April 2022 22:17 UTC](https://community.openenergymonitor.org/t/readings-off/20176/3 "2022-04-07T22:17:18Z")
> [@Robert.Wall](#): > > I suggested adding a note about this to the Wiki in January - it’s not happened. Sorry about that, Robert. I can add that note for you. > [@Robert.Wall](#): > > The addition of a 0.1 µF capacitor across the reed switch completely eliminated the problem [of getting ~2.5 counts per each individual pulse] ---
**Author:** ![Robert.Wall](https://community.openenergymonitor.org/user_avatar/community.openenergymonitor.org/robert.wall/32/38246_2.png) [@Robert.Wall](https://community.openenergymonitor.org/u/Robert.Wall)\ **Post date:** [7 April 2022 22:47 UTC](https://community.openenergymonitor.org/t/readings-off/20176/4 "2022-04-07T22:47:10Z")
Yes please, I think it would be helpful. ---
**Author:** ![NotVeryOriginal](https://community.openenergymonitor.org/letter_avatar_proxy/v4/letter/n/c4cdca/32.png) [@NotVeryOriginal](https://community.openenergymonitor.org/u/NotVeryOriginal)\ **Post date:** [10 April 2022 20:46 UTC](https://community.openenergymonitor.org/t/readings-off/20176/5 "2022-04-10T20:46:28Z")
Robert, when you say across you mean like this? ![image](https://community.openenergymonitor.org/uploads/default/original/3X/8/9/893ea739d1ffe7d30357589262d21ffd02ba1425.png) ---
**Author:** ![Robert.Wall](https://community.openenergymonitor.org/user_avatar/community.openenergymonitor.org/robert.wall/32/38246_2.png) [@Robert.Wall](https://community.openenergymonitor.org/u/Robert.Wall)\ **Post date:** [10 April 2022 21:02 UTC](https://community.openenergymonitor.org/t/readings-off/20176/6 "2022-04-10T21:02:31Z")
Something like that - you haven’t drawn a capacitor. 😆 It should look like this: ![bitmap](https://community.openenergymonitor.org/uploads/default/original/3X/4/0/40b4e964e529eec8cc204fe345c602b69115f5d0.png) ---
**Author:** ![NotVeryOriginal](https://community.openenergymonitor.org/letter_avatar_proxy/v4/letter/n/c4cdca/32.png) [@NotVeryOriginal](https://community.openenergymonitor.org/u/NotVeryOriginal)\ **Post date:** [5 September 2022 20:32 UTC](https://community.openenergymonitor.org/t/readings-off/20176/7 "2022-09-05T20:32:20Z")
Robert, thanks for the suggestion of using a capacitor, it worked!