ya ya i sold all the Bitmain crapola PSUs and now run 2450 watt server PSUs and yes my service averages 228 volts
Firmware ive been collecting since i got my miners.
the biggest savings i made was when i upgraded my PSUs from bitmains apw3 to the server supplies. I tried to make sure they were 96% plat rated and run them on 230volt.
When i started testing PSUs, bitmain was pulling around 1200 watts at 537m. i could get that wattage # down to around 1000 watts at the wall, but my hash rate was crap in my mind when running in the low 400m.
So I actually bought a couple different PSUs with the thought at the time, I wanted something that could also handle the L3s or S9 and not kill me in cost or run at almost 100% capacity while not killing my hash rate. After a crap ton of making up different PSUs and testing i found that the D3s can be some power hungry little buggers.
At 12VDC these buggers can pull up to 122 amps at 537m. Bitmains APWs barely handle that load which makes them run at full capacity all the time hence the big power draw at the socket. When i got around to an HP 2450watts PSU which is rated at 200amps/ 12VDC an 200/240VAC and 13.7 amp AC max, the wattage dropped as soon as i hooked them up. Now even with the 12VDC amp load, which was reduced with this PSU, the PSU never runs at full capacity and i have run 2 miners at reduced frequency on the same PSU, results were not as great but worked. And no i dont have have sockets or wires overheating as with the APWs.
Keep in mind i run each miner a little different but the settings are pretty close and it seems to be the happy medium for each one.
heres a break down + or - about 10% depending on temps
537m = 850w
525m = 720-750
519m = 715-740s
512m = 705-725
506m and under= stays around 710s
this is with board temps in 60s and chip temps high 70s to lower 80s. higher or lower my wattage increases.
those numbers do vary a little with each PSU. Test were run with 1 PSU same model, but with test ports built in.
If i had 480VAC nearby i am sure i could do a bit better, but i am limited to single phase 230 here.
Hope that breaks it down for you a bit and helps. I continue to test so i am sure i will be trying new stuff after the New Year to get my running costs down.
For the nah sayers!!! soon as i get back to playing with the electricity again i will get a pic of the meter hooked into the Socket.
Thanks G