I screwed up. I bought two 24v 50amp hour battle born batteries think in I would have a 24v system. I also bought a 4000watt inverter (24v). I was looking at the instructions and found a sheet of paper that says I need 400ah's to run the inverter. The way I see it I would have to buy 6 more 24v batteries. I am not going to do that and I don't think I can return the inverter. We want to be able to power our steel building for lights, a small TV and power tools. Any suggestions?
In need of help!
- Thread starter ugh
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What inverter is it ?
Can you show a photo of the instructions where it says 400ah pls
Can you show a photo of the instructions where it says 400ah pls
Your 2 - 24v - 50ah batteries in parallel gives you 100ah. Depending on the BMS they have will tell you what is the max discharge rate is. Just as an example if the max BMS rate is 50a ea that gives you a total of 100a at ~25vDC or 2,500w. So no you could not power any item needing 4000w. However anything less than 2500w you could power it with the inverter and batteries you have.
Loads determine supply needs. Lets say your TV is 100w, lights are 75w. If both are on you need to supply 175w from your inverter /batteries. No problem. Now lets say you have a circular saw that you wish to run. It is 1800w. It is within the 2500w ability of your inverter/batteries but due to starting current it might overload them before spinning up to speed. It might be a problem.
Loads determine supply needs. Lets say your TV is 100w, lights are 75w. If both are on you need to supply 175w from your inverter /batteries. No problem. Now lets say you have a circular saw that you wish to run. It is 1800w. It is within the 2500w ability of your inverter/batteries but due to starting current it might overload them before spinning up to speed. It might be a problem.
Rednecktek
Solar Wizard
So you have 100Ah of battery so far? You can run your system on that, it just won't run very long and you may be limited by the amount of power your batteries can provide at once. What's the BMS discharge rating on those batteries?
You've got 2400Wh-ish of energy stored, and that inverter is going to be drawing a good chunk of that just to exist. What's the No Load consumption or Standby Power Draw on that inverter? Take that, multiply by 24 hours, and subtract that from your 2400Wh of power to get an idea of how much usable power you'll have to work with.
You've got 2400Wh-ish of energy stored, and that inverter is going to be drawing a good chunk of that just to exist. What's the No Load consumption or Standby Power Draw on that inverter? Take that, multiply by 24 hours, and subtract that from your 2400Wh of power to get an idea of how much usable power you'll have to work with.
mikefitz
Solar Wizard
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Maximum output current of the batteries is 60 amps, 120 amps with two in parallel. That's enough for an inverter with a 2400 watt load.
The stored energy is around 2500 watt hours.
Thus you can run 2400 watt total loads for one hour or 240 watts of load for 10 hours. That's enough for a few led lights and TV and short term use of power tools.
How are you going to recharge the battery?
The need for 400 Ah of battery would be for battery pack to run the Inverter at full power.
The stored energy is around 2500 watt hours.
Thus you can run 2400 watt total loads for one hour or 240 watts of load for 10 hours. That's enough for a few led lights and TV and short term use of power tools.
How are you going to recharge the battery?
The need for 400 Ah of battery would be for battery pack to run the Inverter at full power.
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Giandel 24v 4000watt inverter. I'm thinking I should buy a couple of bigger batteries
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In general, users who purchase a 4000W inverter are looking to start high-power appliances such as electric saws, motors, etc. Therefore, the seller will suggest that you choose to equip them with a 400AH battery or bigger.
But if you only run lights or TV by the 4000w inverter, two 50AH batteries are enough. But the 4000W inverter is a bit overkill.
But if you only run lights or TV by the 4000w inverter, two 50AH batteries are enough. But the 4000W inverter is a bit overkill.
chrisski
Solar Boondocker
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I recommend a power audit. Need to know how much kWh and peak wattage you need.
When I read that I can’t put that to numbers and the kWh and peak wattage could be anywhere, I think your system can meet it, but you probably fall short in kWh for constant usage. Two power tools at once, probably not.
I purchased the larger inverter and a midnight classic 200 for the larger building we are going build. I don't know exactly what we are going to put in the building but I wanted to have a large enough system to support the things we do choose. I thought that the amps stay the same when in parallel? We also plan to add a wind turbine.
littleharbor2
Solar Addict
Not sure if this is a question of my post.
One of the aspects that many find hard to grasp on electrical supplies is they do not push power. Loads draw it. You can power a small 5 w 12v light bulb with a 12v lantern battery or a car battery. Obviously the car battery will power it for longer. Your home may have a 200a Main Service panel but you likely never reach that 200a in practice. It is entirely based on how much things (loads) you turn on.
Nothing wrong with your 4000w inverter. It can happily supply less than 4000w. It can easily work with your LiFePO4 batteries but the batteries are limited by their BMS to a rated amperage draw. That is where I surmised (I do not know their rating but it is common to be inline with the amp-hour capacity) they were 50a. So what limits the supply in your case is the battery BMS amp rating and their total capacity. If that was not there you could discharge the batteries at the inverters 4000w amount. Quickly.
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