Nope. It looks like it bases the state of charge on voltage, not current in/out. Also, there is this in the description:
Victron MultiPlus 12/500 or Victron Phoenix 12/500 + Blue Power Charger
- Thread starter max514
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Nope. It looks like it bases the state of charge on voltage, not current in/out. Also, there is this in the description:
Lots of options. The % and graphic may not work that accurately.
Here is a 3 decimal meter for $11, your call.
https://www.amazon.com/DROK-Voltmeter-Mounting-0-33-000V-Voltage/dp/B00CJRE1PM
Says it needs an isolated power supply. Not sure I understand that or why it would not be self powered.
Q&A some say put the red and yellow together is fine.
Here is a 3 decimal meter for $11, your call.
https://www.amazon.com/DROK-Voltmeter-Mounting-0-33-000V-Voltage/dp/B00CJRE1PM
Says it needs an isolated power supply. Not sure I understand that or why it would not be self powered.
Q&A some say put the red and yellow together is fine.
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My bad, hadn't read the description.
What would be a decent alternative to the smartshunt?
I see. Easy!
I think this is closer to what you want. It's the ammeter part that you need at a minimum.
I've only used a shunt based one, so I don't know much about the type I linked to.
I've only used a shunt based one, so I don't know much about the type I linked to.
What wire gauge and fuse would you use for the 375VA or 500VA to battery? I calculated the following. Is this correct?
For the 12/375VA
300W Continuous / .89 Inverter Efficiency / 9.3V Low Cutoff = 36A with a very short run -> 8 Gauge?
36A / .8 Fuse Headroom = 45.30 -> 50A Fuse?
For the 12/500VA
500W Continuous / .89 Inverter Efficiency / 9.3V Low Cutoff = 48A with a very short run -> 6 Gauge?
48A / .8 Fuse Headroom = 60A Fuse?
Curveball for the 500VA is that the Victron datasheet says Maximum cable cross-section 10mm² / AWG8 so I feel like I'm missing something.
The Multiplus 12/500 has an efficiency of 90% at 12 volts. You wouldn't want your LiFePO4 cutoff at 9.3 volts. Most of its life will be spent above 12.0 volts. I used 430 watts continuous since that's what the 12/500 is actually rated for. Even with those revised numbers, 8 gauge wire is a bit skimpy.
430W / 12V / 90% = 40A. 6AWG and a 50A fuse would be right.
300W / 12V / 90% = 28A. 8AWG and a 35A or 40A fuse would be right.
Remember that for LiFePO₄ batteries, 10.0V is 0% SOC. 12.0V is just under 10%. Don't let the batteries get below 12.0V. Be sure you set the inverter's LVD to 12.0V or higher.
300W / 12V / 90% = 28A. 8AWG and a 35A or 40A fuse would be right.
Remember that for LiFePO₄ batteries, 10.0V is 0% SOC. 12.0V is just under 10%. Don't let the batteries get below 12.0V. Be sure you set the inverter's LVD to 12.0V or higher.
430 watts / .90 efficiency / 12.0 volts = 40 amps (with rounding up)
40 amps @ 12 volts for 24" round trip distance has a voltage drop of 4.3% for 8 gauge wire.
10mm² is closer to 7 gauge than 8 gauge, but it's still sketchy.
Here is the wire gauge calculator that I use:
baymarinesupply.com
40 amps @ 12 volts for 24" round trip distance has a voltage drop of 4.3% for 8 gauge wire.
10mm² is closer to 7 gauge than 8 gauge, but it's still sketchy.
Here is the wire gauge calculator that I use:
Interactive Wire Size Calculator
Battery Chargers, Inverters, Solar Components, and Wiring Supplies for Boats, RVs, and Off-Grid Applications.
baymarinesupply.com
Oh right, I didn't think about the fact that the specs aren't specifically for LiFePO. Are there other settings I need to worry about?
So if I go for the 375VA with 8 gauge wire, would an inline 40A fuse like this be appropriate?
Domilay 8 AWG Gauge Maxi Blade Fuse Holder Inline Wire 12-24V Volt Waterproof + 40A Fuse https://a.co/d/5Xycvu1
Also, are there any issues with wiring putting the battery in a box and wiring an Anderson connector through the top of the box to quick disconnect the inverter? I've been thinking I could periodically use the battery to power a small trolling motor as well so wiring an Anderson to the motor and to the inverter woukt make that easy.
Would I fuse between the battery and the Anderson connector or between the Anderson connector and the inverter, or both?
Sorry for all the questions. I have a lot of experience with electricity but not as much with low voltage systems outside automotive and sound systems. I just feel safer having someone who knows this stuff inside check my idea. Frying one wire in a lifetime is enough for me.
