Cheap China Solar Controller Failure
For a couple days been noticing higher than the 14.6 voltage,.....going to 15, and even 15.5,....I knew something was not right. The next day it was showing 16, then quickly went to 17+.......I quickl...
Forum Discussion
watt hrs is power used
if you know the items plugged into the iverter used 300Whrs and the lights 23whrs
you can just add it up, you don't have to converte back and forth to amps and ampHrs amphrs*v =wattHrs and the voltage is a sliding scale on DC
a kil-a-watt meter plugged into you inverter
or better yet a Turnigy watt/power meter in the DC power line
and one in the charge line
will tell you exactly how many amp hrs and how many wat thrs
the top line of the display is "at that moment" constant monitor
second line "right" shows the current Watts (8.22a*14.78v
the second line "left" rotates thru the accumulated data, will show amp hrs, watt hrs, peak amps, peak watts
several of us have them,very handy and cost about $30 rated for 65amps
i have mine between my solar controller output and the battery bank
i get daily readings of the exact amount of solar power returned to my system
where you mount them in the circuits determines what you will read
mine measures solar power returned to the system, but not what the converter adds to the batteries, and not the exact charge into the batteries
i used to have one mounted on the inverter power input wiring
for about a year i measured daily use in amphrs and watt hrs
comparing solar watthrs and inverter watt hrs, always gave a more accurate idea of power use and charge
if you know the items plugged into the iverter used 300Whrs and the lights 23whrs
you can just add it up, you don't have to converte back and forth to amps and ampHrs amphrs*v =wattHrs and the voltage is a sliding scale on DC
a kil-a-watt meter plugged into you inverter
or better yet a Turnigy watt/power meter in the DC power line
and one in the charge line
will tell you exactly how many amp hrs and how many wat thrs
the top line of the display is "at that moment" constant monitor
second line "right" shows the current Watts (8.22a*14.78v
the second line "left" rotates thru the accumulated data, will show amp hrs, watt hrs, peak amps, peak watts
several of us have them,very handy and cost about $30 rated for 65amps
i have mine between my solar controller output and the battery bank
i get daily readings of the exact amount of solar power returned to my system
where you mount them in the circuits determines what you will read
mine measures solar power returned to the system, but not what the converter adds to the batteries, and not the exact charge into the batteries
i used to have one mounted on the inverter power input wiring
for about a year i measured daily use in amphrs and watt hrs
comparing solar watthrs and inverter watt hrs, always gave a more accurate idea of power use and charge
jrnymn7 wrote:
Mr. Wizard, I appreciate what you're saying, but I still fail to see any real advantage to thinking in terms of WattHrs?
"2.8 amps @120v is 28amps at 12v, but at 12v its recharge time
so really you are likely using 24a at 12.x volts"
... which could essentially help compensate for some of the heat losses during charging, and thus help average out overall (i.e; actual) Ah usage/replacement.
I generally run between 12.5 and 12.8 volts, so the variance in amps used in any particular situation would be rather insignificant, I would think. So, I used an average of 2.79a, as opposed to 2.81a, for 10 minutes. No big deal. It's all about averages. Likewise, if half the time the fridge is using say 42w, and the other half its using 38w, it all averages out to 40w x 24hrs for 960wh's per day.
So, how does one then figure out how to replace 960wh's ?
