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Also be aware that many fuses are there to protect the WIRING. There should be fuses as close to the battery as possible for this purpose. (this is what fuses/circuit breakers are for in your house distribution panel, to protect house wiring and prevent fires.)

And the phone book thickness Computer Shopper magazine every month.

I think one of the main issues is that LiFePO batteries are significantly larger and heavier per watt/hour than lithium ion batteries. Not an issue for a solar system, but in a hand held tool, every ounce adds up quickly.

Our town installed a 3MW battery to help smooth out the power load. We already have a good sized solar installation (to the point that there was a moratorium put on home solar installs, as they would further worsen the duck curve created by the high solar capability we have now. The battery will...

208 volts wye "Y" is 208 volts from phase to phase, and 120 volts from any phase to neutral.

Here is an RPM vs output graph for the 200 amp rated alternators used by Ford on their police vehicles. The alternator typically turns about 3 times faster than motor RPM from the pulley sizes, so a 600 RPM idle speed will give about 1800 RPM at the alternator. You can see how the output drops...

FYI, Generators use fuel just to run themselves, they are typically most efficient when running at full load. Running it at full load for 4 hours will be more fuel efficient than running it at half load for 8.

Yup, Woz was the engineer...the hands on guy....Jobs was the salesman. :)

If the supply is indeed a CV/CC supply @ 14.2 volts and 100 amps, shorting the output means the output device in the supply is dissipating at least the 14.2 volts@100 amps, or 1.42 kilowatts of heat. That's about the same as a room heater or toaster, heat wise...not surprising if it blows up...

The town I used to live in in Massachusetts had insanely high electric rates. The base electric rate was 14.3cents per Kw/h, but then they added a 10 to 13 cent per Kw/h service charge on top of that (was higher in winter), so the total charge was 24.3 to 27.3 cents per Kw/h. Check the R1 rate...

Also, if the aluminum is anodized, you'll have to remove it where the electrical connections are, as it's an insulator.

You should make it a point that automotive grade components (fuses, circuit breakers, diodes, etc) should only be used in low voltage DC applications. They do not have the blocking or arc supression to be used in higher voltage systems.

As an earlier post mentioned, it is not a good idea to mount them in a small enclosed box, they can dissipate a significant amount of heat when passing large currents, you need to allow that heat to dissipate, not box it up. A 500 amp, 75 millivolt shunt will dissipate 37.5 watts of heat running...

The greater the maximum power panel voltage is above the battery voltage, the greater the benefit of an MPPT over PWM will be. To use some round numbers for easy math, lets say the panel puts out 18 volts at Vmp, current is 10 amps, and it's charging a 12 volt battery. With an MPPT charger, the...

FYI, Peltiers are extremely inefficient, compressors make MUCH better use of the power they use.

Some general figures based on supplied numbers: 15 watts x 24 hours is 360 watt/hours per day of usage. A 12 volt, 100 amp hour battery has 1200 watt/hours total capacity. If you use lead-acid and a 50% discharge, that gives you a bit under 2 days of autonomy, a lithium battery with deeper...

For longer distance runs, you want to maximize the voltage to minimize the current (and the resistance losses in the wire)...within the voltage limits of the charge controller. This same thing applies to the power company, thats why you always see very high voltage lines for cross country power...

Also be aware that fridges can use quite a bit more electricity when they go through their 'frost-free' cycle. They normally turn on a heater to melt any frost that may have formed on the evaporator coils/fins. That heater can use quite a bit more juice than the fridge does otherwise...so even...

It also depends where on earth you are as well, the closer to the equator you are, the less losses will be from atmosphere, going nearly straight up closer to the equator will get significantly more power than a low angle at a high latitude, even if both are pointed straight at the sun at high noon.

FYI, Peltiers are MASSIVELY inefficient compared to compressor type, phase change refrigeration. They can only get 40-50 degrees below ambient cooling, and use several times as much power in the process.

Shunt is a calibrated VERY low value resistor that all current passes through. By measuring the (small) voltage drop across it, you can measure how much current is going through it. Combine that with a voltage measurement and you can calculate power being used or supplied. Example, a 100mV @ 100...

When you parallel panels or strings of panels, you need to be aware of the total current all of them add up to. If it's more than the panel wiring can handle, you need to use a combiner box and fuse or circuit breaker each panel/string of panels separately. The reason is that if a fault develops...

https://download.schneider-electric.com/files?p_enDocType=Data+Bulletin&p_File_Name=0600DB0105.pdf&p_Doc_Ref=0600DB0105

A company I worked for made something similar: http://technicalproductsinc.us/downloads/Kool_Suit.pdf

Can you get a gas fired dryer? Then all the electric does is spin the clothes, the gas does the heavy work of heating the air to dry the clothes. The dryer here is similar for usage. Blue trace is power usage. The first chunk at 7:30AM is electric heat (was chilly this AM), second one about 9AM...

Double check the panel specs, a 305 watt panel at 36 volts should be up in the range of 8-9 amps max current, not 4.5 (10 amps at 36 volts would be 360 watts, so for 305 it should be a bit less than 10).

That sounds much closer. You can also see why MPPT chargers get more energy from the panel than a PWM charger does. The MPPT will find the maximum power point, and load the panel just enough to keep it there (and it runs a new sweep every couple minutes to keep track of changing solar conditions...

The liquid propane in the tank has to vaporize and then pressurize the tank. As you use it, the vaporizing will cool the liquid propane down. The cooler propane won't vaporize or pressurize the tank as well. It's likely the larger units use propane quickly enough that small tanks cant vaporize...

A quick way to check is measure the resistance, and vary its temperature...the resistance should change. Most of them are a simple thermistor in a heavy duty block for ruggedness.