after weeks of testing we now have finished a stable RPi2-System with mSATA-SSD (120GB) on a USB to mSATA-converter and a really unexpensive UPS / USV with open source software. Now we are ready for programming, because hardware works absolutely stable (no SD-Card problems, no fear about power fails).
The UPS with 6Ah gives power for about 3,5 hours (very conservative) and will soft shutdown after this time. When power comes up it starts automaticly and a small script restarts the EVOK-daemon for reusing the UniPi. For more details look @ the UPS-software.
We choosed a divided powering:
a) RPi2 + USB/mSATA-conv. + 120GB -Intel-mSATA-SSD (in summary max. 3,5W => UPS protected)
b) UniPi + 4-AO 0-10V extension (power usage depends on your devices => not UPS protected)
The main problem was finding a suitable Powerbank. We ended with "Tecknet iEP360 with 6.000mAh". Also an "Easyacc U-Bright 9.000mAh" should work. The clou is the software, which you can find here (very difficult to find) - many thanks to this guy!!!:
The powerbank is driven by the powerful DR15-5 power source from Meanwell (You can buy it on UniPi - thanks for that.)
Here are some snapshots of our UPS-system which should drive a heat pump in future. It is mounted on top of a "4-AO 0-10V extension" because of less space in case. Therefore we used a small selfmade adapter of wood (safes the money for a good 3D-printer and fixed it with 1 cable tie.
Hope it will help and many thanks to the UniPi-team for creating this "superboard" and all the useful 1-wire extensions. Nevertheless we will post some optimizing features for the next version of UniPi to make it the first choice on the market.
with best regards