Hi All,
For several months I have been toying with the idea to setup a house energy monitoring system and from what I found out searching the web, I think using the OpenEnergyMonitor system will get me going well and be able to extend the system as I learn more.
However, before I am going to get started, there are a few things I do not entirely understand yet, I hope you can help me. Please forgive me if this has been asked before, I searched the forums, but did not find a conclusive answer yet:
I am planning to use a raspberry pi ("old" model B with 256 mb) as a base station and run emoncms (eventually) on my NAS and be able to access the dashboards both from within the house (on LAN) and when away (through the internet, connecting to the dashboard running at home).
Next I plan to use an EmonTX with three CT sensors connected to three (of the 5 available) groups that are present in my metering closet. If that works, another EmonTX can be setup to monitor the other 2 groups. That will cover all house electricity usage, right?
However, can I then use that setup to also monitor individual appliances, like when the fridge turns on or the washing mache, tv-set, etc? Or would I need to setup separate EmonTX's, with CT sensors connected to those and put the CT sensor around the power cable of each individual appliance I want to monitor?
I am consufed about this as I saw a few dashboards while researching that specified (many) individual appliances in their power graphs, which is handy, but it would turn into a wire spaghetti quite quickly I am afraid, if each appliance would have a separately powerd emontx, with a power adapter...
Can somebody explain if it is possible to measure individual appliances by measuring the group they're on?
Thanks for creating and sharing this awesome open project!
AET
Re: Newbie wants to ask a few questions before starting
Hello and welcome. Taking those points that I can answer:
"I am planning to use a raspberry pi..." That's OK. You can use the PI either as the server running emonCMS (but ideally need to add a spinning hard disk for storage) or as a gateway to your LAN - Jerome has written the software to do that. I think several people has emonCMS running on various NAS systems. You'll need a static IP address of course.
[Two emonTx..] "That will cover all house electricity usage, right?" It would seem so. But when you say "group", is yours a single phase supply or polyphase? The emonTx is designed for single phase only, you ideally need one per phase if you have more than one phase.
"However, can I then use that setup to also monitor individual appliances" Unfortunately not. Trystan Lea did some work a while ago on "Appliance Inference" - the aim being to recognise the change when an individual appliance turned on or off so that you could identify which it was, and I've seen reports that others are also working on this problem. I'm not aware of a proven working system though. I think it's likely that the dashboards you've seen do indeed measure each one separately.
Re: Newbie wants to ask a few questions before starting
Thanks Robert,
All the groups in my house are 1 phase I believe (dutch electricity system). I found the github repo that Jerome has for offloading the emoncms from a raspberry pi to an external installation.
Last question though: If I use two emontx's to monitor the 5 groups, will I be able to specify in emoncms (or elsewhere) that any additional emontx's (monitoring individual appliances on those groups) are monitoring parts of the inputs already received, to prevent emoncms from actually counting the group and the appliances within that group?
Maybe this makes it clearer:
EmonTx1 used to monitor groups 1, 2 and 3 at the meter.
EmonTx2 used to monitor groups 4 and 5 at the meter
EmonTx3 used to monitor fridge (on group 1), oven (on group2) and dishwasher (also on group 2)
The data EmonTx3 is monitoring, is part of the data EmonTx1 and 2 are already monitoring. What I don't want is that the values measures from all three EmonTx's are counted/added up, because that would give a wrong total energy usage.
Hope my question is clear... :-)
Thanks for reading!
AET
Re: Newbie wants to ask a few questions before starting
I wouldn't advise doing it that way, but you can certainly do it. You can subtract one input from another inside emonCMS, with a little ingenuity. If you go to emoncms.org, under Using Emoncms -> Input processing, you'll find a list of operators. To subtract, you multiply by -1 and then + input. You can send the result part way though the calculation to a feed, continue and send the another intermediate result to a different feed, continue and send the final result to a feed. (A feed is what gets stored for display, inputs are temporary and only exist between the time the data is received to when the calculations are done.)
(You really need to do this a few times to understand how the processing works.)
Re: Newbie wants to ask a few questions before starting
haha, thanks for your reply. I guess I am in for a little bit of experimentation after I get the hardware :-) I guess I will start with just the two emontx's to monitor the groups coming out of the meter...
Re: Newbie wants to ask a few questions before starting
If you register an account, you can experiment while you are waiting for the hardware. You can make up values and send them from a web browser! The Input API help tells you the data format and gives you simple examples.
Re: Newbie wants to ask a few questions before starting
Thanks, I read that somewhere already, so created an account and will get experimenting tomorrow! Awesome, can't wait! Thanks Robert!
Re: Newbie wants to ask a few questions before starting
Yay! Just placed an order for the hardware to monitor all 5 groups...
However, another question popped up:
I played around with emoncms a bit, but did not find this (yet?): Is it possible to add a form on a dashboard to manually enter data into emoncms? I have (very) old utility meters in the house that do not emit any sort of pulses, so I am thinking about a way to enter the numbers on the meters manually on a regular basis.
Is such a thing possible from within emoncms?
Re: Newbie wants to ask a few questions before starting
I think the answer to that is no. You could clearly do it by customising your local copy of emoncms, but I don't think it's likely to be available on emoncms.org any time soon - because the site is all about building the kit (that you've just ordered! ! !) to send consumption data automatically!
(What you're really asking is how do I run a check automatically?)
I've never felt a need to do it, but I can't see a reason why you can't have a bit of software that does what the browser or the emonBase does and submits the data using the structure in the API help. It would appear as an Input and you'd log it to a Feed just the same as the rest of the data.
Re: Newbie wants to ask a few questions before starting
I guess I can whip up a page that offers a form to the user to enter meter readings and posts them to emoncms then :-) Shouldn't be too hard to do.
Thanks again!


Dose: ~6mg (oral aqueous)
Time: 12:30
[written at t=0 (12:30)] I dissolved 100mg into 125grams of water at room temperature. 90 minutes later, it still hasnít really dissolved, but rather formed a suspension. Itís kind of annoying. I think it will dissolve eventually. I am a little worried about the accuracy of my dosage. The water I used was not distilled, but rather tap water (drinking fountain) that I let sit exposed for 3 days to get rid of dissolved chlorine. I hope it worked.
Just ingested it Ė 7.5mL of water containing 6mg 2C-P (1mg per quarter teaspoon). Taste lasted for under 5 seconds. It was somehow reminiscent of wasabi. I didnít get much sleep last night, maybe 4.5-5 hours. I hope this doesnít affect the experience too heavily. I avoided my usual morning Adderall, caffeine (coffee), and citicoline. With the caffeine and citicoline, I was not worried about interaction, but rather I wanted to avoid the laxative/gastroprokinetic effects I experience with these drugs. I have been off mirtazapine for 5.5 days. I took melatonin last night and, of course, smoked cannabis. Havenít smoked weed (yet) today.
This was my first phenethylamine. I would liked to have started with a perhaps gentler or more mild 2C.
[t=.25h] I feel different. Relaxed but excited. Bit of a headache.
[t=1.5h] I feel sick. GI upset (mild). Nausea (was extreme for a few moments).
[The following was written the next day, before 3:00pm] The GI upset and nausea went away (mostly) for the next ten hours. Next day there was mild diarrhea. I got the ďbody kinksĒ people speak of. This seems vasoconstrictive. This, along with a report of sinus clearing (see Pihkal) suggests an adrenergic component. I worry about potential cardiovascular damage.
The experience was not fun. It was far from pleasant. I experienced no severe emotional distress while on the drug. However, around the 9th hour, I started getting bummed out about the duration. I just wanted to sleep. I was exhausted. This drug is physically and psychologically very draining. Regardless, I see incredible therapeutic potential in this drug. Even at my low dose (6 mg), I realized how intense and unforgiving 2C-P could be.
I spent the day lying on my bed. There was none of the stimulation people have spoken of. My body hurt, and movement was very uncomfortable. Fortunately, I saw little reason to move for most of the next eight hours. In fact, I felt rather tired. The sound distortion was pretty intense. It would mix somehow with my somatosensory awareness (skin was more sensitive, and objects felt very different; heavier and rougher), causing the perceived shape of my body to become distorted. Occasionally, there was considerable hilarity.
That night, I used 350mg carisoprodol (sedating muscle relaxant) and 12.5mg doxylamine (pretty much like Benadryl). I feel like this may have helped immensely with the physical pain and insomnia. I suffer from chronic insomnia, so I was pretty concerned about not being able to sleep.
The next day, even after eleven hours of spotty sleep, I feel drained, emotionally and cognitively.
I am also thinking in some psychedelic thought patterns. I feel pretty empathetic, and I donít think I can be angry, arise such a cause. This reassures me about 2C-P, and I will try it again at some point, despite many unpleasant aspects of this drug. In the meantime, I hope to get more enjoyable effects from 2C-I and 2C-C.
[The following is written around 5:00pm the day after ingestion] Or at least, I did, until I smoked a little weed. Then I felt great. Colors were vibrant, and the world around me was beautiful and fascinating, visually. It was in fact, a very nice, sunny, bright day.  My short term memory is completely shot though. Next time I ingest a psychedelic, I will try smoking weed with it. I have been reluctant to do this so far due to worries of extending the experience too long.
Experience Reports are the writings and opinions of the individual authors who submit them.
Some of the activities described are dangerous and/or illegal and none are recommended by Erowid.