Earnest Tilley wrote: »
UPDATE! That inverter i got the one that fried when i first got it and got another just like it is a ROAD PRO. I had a few beers tonight and forgot to turn the ac off im a little tipsy now but the window ac powered off! I went and checked the voltage on the batteries to make sure i did not mess them up to bad and it was at 12.01 so apparently that inverter shuts down at 12v which is good to know since there is NO knob to change the cut off on it. My next system will have one but im really happy it shut off at 12v. If i where you i would call the people your ordering your panels from and see how much more the 85 watt 24v panels are i think there right around 30 bucks more. It will probable save you alot of headache in the long run if you go ahead and get the 24v ones and set your system to that. Everyone wanted me to go with a better 24v system when i started but i did not listen. If you dont have alot of money to buy multiple 12v 24v systems to run separate things you might want to start with a 24v system. If your doing it as a hobby or just as fun to see what you can do with it get whatever but make sure you put your fuses in do not burn up your system right after you get it that would not be cool .
Earnest Tilley wrote: »
ok after adding the fuse blocks to my solar panels it dropped my voltage going into the charge controller to 13.8 where i was getting 18 - 19v i added gold plated connections in and out of the fuse block, have know idea if that has anything to do with it or not?
ggunn wrote: »
Adding fuse blocks, gold plated or not, should not reduce your voltage by anything like that amount. There is something else going on.
john p wrote: »
IM not wanting to get into another discussion on bus bars again but just reposting the post from a long time ago and the results for FARMERJOHNAZ to see if this answers his question..
It shows the very tiny losses you get from using cheap copper tube available from any hardware store.. you just hammer or put in vice the ends of the short lengths of tubing to flatten them then just drill a suitable sized hole each end..
Here is the results of resistance testing and mechanical destruction testing of lugs on copper wires as used in battery interconnects and similar usage.
A total of 10 lengths of copper water pipe was purchased from hardware and plumbing supply stores. The 2 sizes purchased had inside diameters or 1/2 "(12.5mm) and 3/4" (19mm) thickness ranged from 1.25mm to 2mm. All pipe lengths were 10ft (3050mm)
Each size and thickness of pipe was purchased from a different supplier
All measurements were carried out on a calibrated desk multimeter.With a accuracy of+ or - .02%
1.1/2 pipe 1.25mm =.0012 ohms
2.1/2 pipe 1.25mm =.0013 ohms
3.1/2 pipe 2mm soft = .0008
4.1/2 pipe 2mm hard = .0009
5.3/4 pipe 1.5mm = .00065
6.3/4 pipe 1.5mm = .00061
7.3/4 pipe 2mm soft= .00042
8.3/4 pipe 2mm soft = .00041
9.3/4 pipe 2.2 hard = .00040
10.3/4 pipe 2.1 hard = .00039
As noted the resistance was given for 10ft lengths of pipe . If we are going to use any of those pipes as barttery interconnects etc obviously the length used would be about 8" to 10 ", so to get the resistance you would have to divide the above resistance figures by about 12.
To give worst case example the 1/2 pipe 1.25mm at .0013 ohms per 10ft divide by 12 =.0001ohms per foot
THe loss across that pipe used as a battery interconnect would be using 24v connected to a 100 amp load = 40ma
Now lets see how that compares to using a #2 cable and 2 lugs cable resistance = .00052 plus 2 crimped lugs at .00046 total resistance = 99ma loss
Any talk about wondering about losses for 1000 ft of ANY 1/2" copper pipe can clearly be shown to be a pointless exercise. and it way surpasses using #2 cable and the fact is most people would only be using #4 cable as interconnects.With far far greater losses.And as I said in a much earlier post use 3/4 " copper pipe.No matterif it has many impurities its still far far ahead of #0 cable for battery interconnects
Tests involved to measure lug on wire resistance and mechanical strength.
the tests involve #4 cable and closed ring closed tube copper lugs 2mm thick
1.Lug compressed with 500lb pressure on 3 serrated teeth jaws. resistance .00023 ohm.Lug then tested for breakaway
.seperated from cable at 223lbs pull
2,Lug compressed with 500lb pressure on 3 serrated teeth jaws then lug heated and filled with resin cored solder.
resistance .00015 seperated from cable ..failed as cable broke before cable seperated . test pull 325lbs
3. lug and cable resin cored soldered only. resistance .0008 seperated from cable at 127 lbs
As you can see solder only is not good. As a further test the joint melted when a 140a load was connected to the cable and a 12v battery to the lug. Obviously not good.
As you can see I didnt get much work done for employer the day I did all these tests, believe it or not it took 3 of us to do the tests .my work partner to verify the results ..As to do any destructive testing a workplace safety officer has to be present.
Hope some of this helps people understand a little more about cables lugs copper pipes..
Earnest Tilley wrote: »
ok i have a kill a watt meter for my ac side that tells me how much power i have going out and a volt meter to tell me how much volts i have coming in. Do they make a watt meter or something like that, that tells you how much power my panels are producing?