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Everything posted by plonkster

  1. Emoncms no longer for free

    Yup, that was more or less the intent. And you said you tried some free offerings. I wanted to mention one that isn't free, but so cheap that it's worth it. It's cheaper even than Amazon's virtual servers, and these days with docker taking over the hosting world... you pretty much build your app into a docker container and just deploy it anywhere. Edit: In fact, someone's done the hard work already :-)
  2. Emoncms no longer for free

    Digital Ocean. 5USD a month for what they call a "droplet". 1GB memory, 25GB disk, 1TB transfer. Ample for running emon and most other things.
  3. Emoncms no longer for free

    Hetzner charges extra for Windows servers. Why on earth would you host emon on windows... WHY!? (unless of course you're also using it for other windowsy things...).
  4. raspberry pi 3, where buy?

    First stop, a buddy of mine made this search engine that searches all the most common hobbyist sites (including the one TTT listed). I doesn't search RS-components though, and they aren't necessarily always priced that badly, though you have to factor in shipping. So basically check these two. Also check XT Comp on BoB, no Pi as far as I cam see, but sells some nice related stuff and I've had good experiences with this seller.
  5. is this a normal charge pattern?

    You're using a BMV right? Yes this is normal. But it might not be good. Quick explanation how the BMV works. A typical lead acid battery, while at absorption, will show 1) a voltage higher than 2.25V per cell, 2) current that's dropping off as the battery accepts less charge. So when the battery is 100% full it will typically accept only a few amps at most. So what the BMV does is look for a condition where the voltage is high and the current is low. This condition has to hold for a certain period of time. You can configure all three these items on the BMV: the charged voltage (setting 02), the tail current (setting 03), and the charged detection time (setting 04). What sometimes happens, under just the right conditions, your loads and the available PV balance such that the remaining charge current is below the tail current, the batteries are full enough to rise above the charged voltage, and this happens for long enough that the BMV detects it as full. The battery may however not be completely full. The trick to get around it is to set the tail current nice and low (about 1% of the Ah capacity, maybe 2% for some flooded cells), and the detection time should be set to something like 15 minutes. You will also have to manually charge the batteries fully now to resync the BMV.
  6. Pro Combi S Pure Sine Wave 12V 1KW for sale

    Oh I believe you, no worries! I was just wondering :-) It's a "tick the box" indication, I didn't realise. It looks like it's still in excellent condition.
  7. Pro Combi S Pure Sine Wave 12V 1KW for sale

    The inverter in the picture looks like a 24V inverter. I assume you changed to 48V and you're selling the 24V model?
  8. Current Water Affairs.

    The analogy breaks down a bit. Imagine you had a contract with Woolworths to deliver certain goods every other day, as needed. Imagine they bought a truck to service those customers, seeing as it was backed by guaranteed (as much as a contract can) income. If you decide one month not to order anything, they still have to fund the truck. Electricity and water is a bit like that: Even if you use nothing, the transformers, lines, reticulation system, all still needs to be maintained. With that said however, it by no means makes it fair to inflate connection fees and attempt to make up shortfalls at the expense of your customers, especially when you technically hold a monopoly. So there I'm agreed with you.
  9. Axpert SCC MPPT v4.12 Firmware

    I have no idea :-) Of course none of this is foolproof. The problem with copy protection is that in all cases you usually have to give the consumer everything he needs to actually get the content out... and if you can get it out, you can copy it. It's just a matter of required effort. (I wish music producers understood that).
  10. Axpert SCC MPPT v4.12 Firmware

    Generally speaking, not necessarily in the specific case of this equipment, MCUs have a feature (on the atmega it's called fuse bits for example) that you can activate that disables the reading back of the code. So during development you will likely leave this feature off, and then you will enable it when you ship the final product. Sometimes a manufacturer will leave it open, possibly because in the rush to get it to market it might be forgotten, possibly because it isn't deemed worth that much, or something, and you'll be able to read the code back with a suitable ICSP interface for that MCU. But it is pretty common for this to disappear in time. Don't know if anyone remembers the film Entrapment. Catherine Zeta Jones and Sean Connery. There is this scene where she is bragging about stealing something, how she stole it and dropped it in the mail room, literally mailing the loot to herself. Connery then produces the stolen item, to her amazed face, and explains to her that it is always easier to break into the mail room. Similarly, if you want to steal a company's data: Find out where they keep the backup tapes. Back in my day... I kept them on a shelf in my home. Cheap off-site storage you see. Remember when Hetzner's FTP backup servers were compromised? That's why it is a big deal. If you want to steal firmware, steal it from the publicly available firmware downloads rather than attempting to read back a chip. And right there... that is where the next thing kicks in: The firmware is quite often encrypted nowadays, and they key to decrypt it is inside the bootloader on the MCU... again suitably protected so you can't read it back. Now it seems Voltronic might still have some open holes here and there, but I would expect them to close it in due time.
  11. Laundry needs hot water

    Geeez, now I understand why "Scheduled charge/discharge" is such a much wanted feature. Fwiw... it's coming soon on planet blue. You will be able to charge (from the grid) at low-tariff times and discharge again at peak time. At over R2/kwh price difference, with a good set of lithium ions... you'll pay for them pretty quickly.
  12. Laundry needs hot water

    1.07 peak tariff. Our LifeLine tariff isn't even that low. Then again, if I had to guess, George likely has a connection fee and this might be ex-VAT, so the actual cost once you add that in is likely a tad higher.
  13. Current Water Affairs.

    Rain in April is already a good sign. Last night we were listening to the water running down the gutter... so beautiful. This morning, we realised the water is still running and the skies are clear. Turns out my geyser had burst. While I was looking for my shoes to investigate I heard this loud clatter upstairs. Ceiling had dropped out. Wonderful. Just wonderful. So I had a plumber here earlier to just cap everything off... so two days of cold water, and then a new geyser. Again. Installed July 2013. Didn't make the 5 year warranty. Third one in a row to not reach it. Also, two weeks of water down the gutter. I'm almost more upset about that.
  14. Wind Turbine Overview

    The deception continues.
  15. Wind Turbine Overview

    That's what's so worrying about it: The guy actually knows what he's talking about. You can actually get drawn in...
  16. I noticed you guys have a very favourable forecast today. Hoping you get some rain. It should pass this way around noon, Looks like it will also hit the mountains towards the east where we get most of our run off. Holding thumbs and looking up today, in more than one way.
  17. The slightest bit of extra draw on one battery, even just 50mA, will cause imbalance in the long term. That's why Chris said that if you have a balancer on there you might be okay: What the balancer will do is pass some current from the other batteries to compensate for it, so you get a kind of cheap buck converter (which technically is how the HA02 works, as I understand it it is a 1:1 DC/DC converter of sorts) that powers the fan from all 4 batteries. As long as the draw is lower than the current the HA02 can pass you can get away with it... BUT... I still wouldn't do it. Hacks are hacks... do it properly.
  18. Don't you need a PWM signal on yellow to make it work?
  19. What are you trying to do? Will a 12V fan work on a 12V battery. Yes, of course it will. I'm not sure what you're asking.
  20. Wind Turbine Overview

    I remember the gwstore debacle. I didn't know it was this bad.
  21. A situation that we may or not be aware of.

    The most internally consistent report I read is this one. I'm inclined to believe it.
  22. It will make very little difference to me whether they switch me over or not. I buy 600kwh every month. The total cost to me would be about the same. I wonder what they mean by "eligible". Might be an euphemistic way of saying "we want to move you cause you're a drag on our income".
  23. Inverter powering 1.1kW pump

    By the looks of it you have a nice 0.5V drop on that cable. Inverter is showing 24.1V while your meters on the other side says 24.6V ?
  24. Battery lugs and terminals

    wantitall is an import site for foreign stuff. You only buy from them if you really really really want it. They are not cheap.