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The following are common units and their abbreviations. Note that unit abbreviations are case-sensitive. While some units can be understood when written incorrectly, some have a completely different meaning if the wrong case is used. Avoid any possible confusion or ambiguity and use the correct...

You don't want a Victron inverter/charger. Why would you want something that will actually perform at its rated specs all day long without issue? Why buy something that you can get support for from any Victron dealer? And you certainly wouldn't want to combine your Victron inverter/charger with...

Agreed. I love a good IPA. But a friend of mine, who doesn’t like IPAs, says that IPA stands for “I’m a pretentious a-hole” :)

I'd worry about the two wires putting some bending or twisting stress on the fuse. The holder keeps things stress free. Putting a Class T (or any) fuse between two pieces of big heavy stiff wire (for example, 2/0AWG or 4/0AWG) without any support is going to result in some unwanted stress on the...

5000W on a 12V battery! Really? That's up to 500A being pulled from the battery. That's a ridiculous amount of current. That needs wire much larger than 4/0AWG. For 5000W you really should be at 24V or 48V, not 12V. What does the manual for the inverter suggest for wiring?

Out of all the inventions in the last 100 years, the dry erase board is probably the most remarkable.

There are two main values to worry about when choosing a solar charge controller (SCC). 1 - the max input voltage and 2 - the max charge current. When you look at Victron charge controllers you will see models such as the 100/20 or the 150/45. The first number is the max input voltage and the...

Remember that no matter how much solar you have, it will only provide what you need. If your battery is full and there are no loads then you will get nothing from the panels. Turn on a bunch of loads and the SCC should provide more current. Drop the battery down to 70% (or some non-full...

18Vmp x 3.12A (Imp) = 56W. How is that a 300W panel? Those specs don't make sense.

tl;dr - No you can't replace a BMS with a shunt. A BMS (battery management system) is there to monitor, maintain, and protect the cells of your LiFePO₄ battery. A shunt is a device that measures the amount of current flow. These two devices have two completely different jobs that are not...

Don't forget that you are getting lots of summer sun. See how it's doing in 4 or 5 more months. You won't think you are over paneled then.

Actually you can't. You have a max PV input voltage of 100V. This is based on the temperature adjusted Voc of the solar panel array, not the Vmp. With a Voc of 37.0V, 3S would be 111V which is obviously over 100V. At best you could do 2S (two in series) for a total of 74.0V. I assume you are...

1000W for 3 hours is 3000Wh. But through an inverter it would be about 3500Wh. A 48V (51.2V) 100Ah LiFePO₄ battery is 5120Wh. So the one battery can power the A/C for 3 hours (it can actually run it for about 4 hours). To replenish the 3500Wh used by the A/C, assume 5 hours of solar. 3500Wh /...

The Victron SmartShunt isn't for protection of any kind. It's to provide information about the status of your battery.

If you have that much amperage then you have enough panels in parallel that each string should be fused. If you have enough amperage to be too much for the MC4 limit then you need to be using a combiner box which won't have any MC4 connectors. If you have too much amperage for the wire then you...

I'd love to see a clear, concrete example comparing series vs parallel arranged solar panels. I know there are lots of videos on the subject but they all have serious deficiencies. Here's what would interest me at least: You need 6 identical panels, somewhere in the 200-400W range each. Make...

That's a rude thing to say. :) Aren't typos fun?

I wouldn't call that a big advantage of 24V. If you have half the battery then you have half the total power as well, regardless of voltage. You can easily make a 48V battery that is the same cost as a 24V battery. Both will have the same power. It's just that the 48V will have half the Ah of...

The lights you linked have the following note: These 12VAC LEDS require a special AC powered fixture. So you would need an inverter to power these from DC. It would be far more efficient to find 12VDC lights so you can avoid the DC -> AC losses of an inverter.

Hook everything up with just one battery and fully charge it. Then swap out the battery with the other one and fully charge that one. Do both with no loads. Once both are charged you can hookup both batteries in parallel and you are good to go.

Start with the basics. V x A = W. Volts times amps equals watts. That is as simple as it gets. The k prefix for any unit simply means 1000. Example: 1kW = 1000W. The symbol h is for hours. When you see Ah for a battery that is the battery's capacity. A variation of the basic formula of V x A = W...

I'm the opposite. I love a blank sheet. There's so much potential. So much to learn. So much to figure out. That's my favorite part of any project. By the time the sheet of paper is full I'm getting bored and I'm ready to move on to the next project and learn something new. I have such a long...

Use some scrap wood on top of and below the copper bar when drilling. Drilling through the clamped wood/copper sandwich will help with bit wandering and burrs.

Power is pulled by things that need it, not pushed by things that provide it. Your solar panels are not pushing 1000W into the SCC when unneeded. The SCC stops taking power from the panels no matter how much sun there is. It's like all of the outlets in your house. Electricity isn't being...

Depends on your use case. Provide more details about how your battery will be used and under what conditions. LiFePO₄ is great for many uses but not all. And don't run off and order some LiFePO₄ cells until you fully understand that LiFePO₄ fits your needs and then what it takes to build your...

It makes no sense for negative wires to be the same length as positive wires. If you have a battery bank made of 6 batteries in 2S3P, for example, then the following must be true: - The three series connections should be the same length as each other - The two or three positive parallel...

I used wood to drill my 1/4" copper bar stock when I made my bus bars. Seemed to work well enough. Maybe the ideal way is to use one piece of metal with the correct sized hole on top of the copper. You don't need to keep drilling new holes that one piece of metal. Just reuse the same hole over...

The idea is to wire for the hardware. It’s a 1kW inverter. Wire it to be used as intended so it’s not a surprise (or possible hazard) when someone tries to use the full potential of the inverter.

1500W load / 12V battery = 125A. That's why your 100A breaker trips. To fully support a 3500W inverter at 12V (which is really too much) you need wire capable of handling 340A and a 425A breaker. To handle 340A you should have a pair of 2/0 wires between each connector. I have no idea what wire...

You can put more than 6kW of panels on a charge controller that only supports 6kW of solar. You'll never get more than 6kW at any one time but having more panels gives you more production during a longer portion of the day or under less favorable conditions. Just be sure you don't exceed the...

Assuming the 50A is the rated max output current to the battery then if there is enough wattage coming in that would exceed that output current then the output current is simply limited to the max, 50A in this case. Let's say you have a 12V battery and it is at 13.6V. The 50A output would be...

I suggest you use the 1/0AWG for all battery connections. Think about what happens if one battery shuts down for some reason. Now the load is across 3 batteries, not 4. What if two shut down? Now the load is across 2 batteries. 6AWG wire will become a safety issue. Also, using 1/0AWG for all...

What is a 25kW 280Ah battery? Assuming you meant 25kWh then 25kWh / 280Ah = 89.3V. That's a strange battery voltage. Something about these numbers isn't right. A 12V 280Ah battery would be 3584Wh and it can handle a 2kW load for 1.79 hours. A 24V 280Ah battery would be 7168Wh and it can handle...

Before putting batteries in series you need to balance them. This means you need a 12V battery charger. Charge each battery separately to 100% SOC. Then put all four in parallel and fully charge them together using the diagonal attachment method for the charger. Once charged, disconnect the...

You shouldn't need a battery balancer. The trick is to properly balance the two 12V batteries before you put them in series. If done correctly you shouldn't have any problems after that. Worse case you might need to rebalance the two batteries once a year. Start with a good LiFePO₄-friendly 12V...

I'm assuming you are talking about the (currently removed) fuse hooked up to the charge controller. It's hard too see in the picture but it looks like the charge controller has 20A output. So a 20A fuse is too small. The approach is to choose a wire that can safely handle the amps. Then you...

As stated, just 1 50A MPPT can handle both 300W panels wired in either series or parallel. Do not attempt to wire up 200W panels with your two 300W panels to the same charge controller. First, 600W is just about the max you can use on a 50A charge controller on a 12V system. Second, mismatched...

FYI - Wh (watt-hours), not Ah (amp-hours) The EG4 is 48V (51.2V) 100Ah which is 5120Wh (not Ah). At $1,500 that is $0.29/Wh The 16 3.2V 304Ah EVE cells would be 15,564.8Wh (not Ah). At $2,467 that is $0.16/Wh DIY gives 3x the battery at less than twice the price. Don't forget the EG4 is ready...

Would it be possible to update the forum software so it strips Amazon URLs to the bare minimum needed? Many people paste Amazon URLs into posts and most of these URLs contain far more junk than is necessary. Many look like this...

battery -> lug -> flat washer -> split washer -> nut You want the lug flat and tight against the battery terminal for best contact and least resistance. This is basically true for all electrical connections. Never have washers or other fasteners between the key electrical parts. The fasteners...

I think what you mean to state is that you used a total of 5kWh over the course of 16 hours and 10kWh over the course of 8. So you used a total of 15kWh in a day (24 hours). You can't just say 15k. You need a unit. Here's a quick overview of how this works. Let's say you have a light that uses...

Why? It is actually a valid discussion. I'm sitting 5" above 5.2kWh of LiFePO₄ batteries and a solar charge controller, and my back is 6" from my 2kW inverter (though it's not on at the moment) as I type this.

Rated panel wattage is Vmp x Imp. You are measuring Voc and Isc. Voc x Isc is about 33% higher than rated panel wattage. So take your Voc x Isc and multiply by 0.75 to get expected max wattage. Of course that's all based on perfect STC which you certainly didn't have when you made your...

Sorry but over paneling has nothing to do with AC or an inverter. It's only with regard to a solar charge controller and its rated max wattage which in turn is based on the charge controller's max battery charge current (times the battery charge voltage). Granted, some "inverters" (all-in-ones)...

Agreed. I have a 7x14 cargo trailer converted to a camper. The cargo trailer came with a small 12V battery in a box mounted to the side of the tongue. That battery is for the trailer's brakes. The 7-pin has a 12V line that controls the trailer's lights. I left all of that untouched. As part of...

Here's a final update. I ended up completely changing my rack design. The feet I was originally planning were going to be 1) a giant PITA and 2) far from ideal. My finished rack was much easier and it is much stronger and safer. But it is heavier. It consists of two main Superstrut (Unistrut)...

I would recommend that you do not use an inverter at all. The cameras require DC power. It will be a lot more efficient if you do not converter DC (battery) to AC (via inverter) and back to DC (via camera power brick). As for batteries, the 100Ah AGM is too small to power the cameras for a day...

An "all-in-one" is a single device that has an inverter, charger, automatic transfer switch, and solar charge controller. That's it. No solar panels, no batteries, no wires. Nothing strange about this. Everyone has different needs.

Options: 1) Spend a couple thousand dollars buying solar panels, a solar charge controller, inverter, batteries, wires, fuses, and a few other little things plus all of the time to mount the panels on the roof and hookup all of the other components. 2) Spend ??? dollars having power run out to...

You have an 85A charge controller so you need 4AWG wire and a 100A fuse between the SCC and battery. You can wire the charge controller directly to the battery just like the inverter. Though that may not be ideal. Using bus bars makes everything a bit neater and more organized. Plus it avoids...