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  1. Jeg fikk det til nå. Oppdaterte til siste beta av z-wave plugin, og ekskluderte/inkluderte devicen pånytt (secure) ?
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  2. I'm not sure if ArnieO has moved forward with this, but for those wondering I'll give an update from my efforts. After a little bit of troubleshooting, I now have a self-powered solution up and running this week. I'm running on an Aidon meter from Lyse. It seems to be running with no problems, and the power supply for the ESP is stable. :) My circuit is very similar to that ArnieO posted in the bigger thread. Rather than the LTC3639, I went with the LTC3642. I found it to be a bit simpler to implement, and the simulations showed it to be slightly more efficient. I'm using the latest sketch in the GSKJOLD repository, and measured the ~average current consumed to be ~25-30ma (there is some uncertainty here that I need to measure). I chose 620k for the Rset of the 3642, which should support a maximum load current of 30-35ma. In testing the DC-DC, it was stable up to ~38ma. Above 38ma, it started to drop in output voltage. I went with a 220uH SSR6603 inductor...it is tiny. Attached is a picture of my prototype board...it has some extra wires, no RJ45 jack and extra caps stuck on. The DC-DC is the bottom left corner. I've got a second board cleaner without all the mods and a RJ45 mounted that is running currently. Also attached is my schematic for the DC-DC supply. Challenges: Input voltage to the converter during transmission Originally I had a 15ma current limiter (NSI45015) instead of the 20ma. During the low bits at 12V, the converter needs ~15-16ma on the 12V line. the NSI45015 was clamping the voltage and causing the 3642 to go unstable. It would not recover without a clean power cycle. Because of the design of the DC-DC, it cuts voltage to the inductor at the programmed level. This seems to limit the maximum current draw from the HAN port by itself. The only reason for the NSI45020 is to limit the inrush current charging the input capacitors when plugged in. This seems no problem for the Aidon meter, but depending on the sensitivity of the Kamstrup this may be a problem as the currents needed at the 12V level are too high. Maybe we could increase the 33uF input capacitor so currents are only drawn during the 24V periods of the HAN signal? ESP startup power draw The ESP pulls ~70ma with peaks of ~2ms of ~150ma during transmission/acquistion. We knew this would require energy storage to support. Once fully started and configured, the ESP can stay alive with ~10mF of capacitance on the 3.3V supply. I'm not sure what voltage it dips to on transmission, but >2.6V I believe. During startup the ESP draws long periods (several seconds) of ~70ma current. This requires a 1F capacitor to maintain voltage during the startup without modifying the firmware. I went with the DGH105Q5R5, a 5.5V 1F supercapacitor. ESP brownout on powering up The 1F cap causes a very slow ramp of the 3.3V, taking well over 15 sec (probably 1min?...i didn't measure). This slow ramp of the 3.3V does not let the ESP start cleanly. At best it simply does not start even as the voltage gets to 3.3V. Worse it can go into a brownout condition and draw current such that the DC--DC can never make it to 3.3V. I've modified my firmware to include a Vcc check on boot, and the device goes into deep sleep if the input voltage isn't close to 3.3V. I've also put similar calls into the wifi and mqtt connect sections so that the esp will not brownout if there is a problem connecting to either...it will instead go into sleep cycles waiting for the voltage to recover. We need to implement a voltage supervisor circuit into the design to ensure a clean boot during a power cycle. Due to the input voltage drop from the supercap, we need a supervisor with a large hystersis. Something like an MIC2778 (http://ww1.microchip.com/downloads/en/DeviceDoc/mic2778.pdf) should work, but I will instead go with one that has a manual reset function included. Maxim makes a bunch, TI has a paper on how to program additional hystersis, etc. More work here is needed. As for now, I have to manually reset the esp when the voltage gets above ~2.4V. From there it takes care of itself waiting for the voltage to reach the 3.3V level before fully starting up. I've measured the average current consumption on the HAN line at ~4.9-5ma averaged over several minutes. In principal it seems possible to build one close to meeting the 6ma limit of the Kamstrup. For the Aidon and Kafia meters, this should work mostly as is. If someone wishes to prototype from here themselves, I have extra bare PCB's.
    1 poeng
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