Hello. I’m new here. 1st post. Looking for general input for electricity… remote cabin

[Nan_wpg]

Under. Gotta be above freezing all the way down in the cells.

Breakers are a handy thing for that, built in disconnect.

The advantage to rackmount batteries is that it's becoming a common form factor. The downside to them is that it's really hard to find 24v rackmounts anymore. If you were to go with a EG4 3Kw unit, or the MPP-3048LV, both would get you 3Kw of inverter, the charge controller, generator hookup, etc and get you into the 48v range where rackmount batteries are common. If you go that route spend the bit extra on a Trophy battery and it takes care of the heating and low temp and all for not much more than a basic 48v rackmount battery. The Trophy batteries also come in larger capacities than 100Ah which is pretty handy for those long winter days.

Just put in the notes that when the alarm goes off go fire up the generator. When the generator winds down (not charging the batteries anymore and just idling) and gets quiet go shut it off.

Over 30 wasn’t a typo. I’m Canadian so I meant 30 Celsius (hot). Not 30 f which is our zero. Lfp charging temp is 0-30 Celsius.

the rack Mount have their own breakers so I could just use that. I have no issue going 48. Seems like that where everything is going.

 

[Nan_wpg]

Trophy makes sense. It diverts charging current to heat battery. Our cabin see temp from -40c to sometimes +30c.

 

[Rednecktek]

Over 30 wasn’t a typo. I’m Canadian so I meant 30 Celsius (hot). Not 30 f which is our zero. Lfp charging temp is 0-30 Celsius.

the rack Mount have their own breakers so I could just use that. I have no issue going 48. Seems like that where everything is going.

Ya silly Metric people with your sensible measurements and logical units.

Lots of people say to discharge the battery to about 60% or so before shutting it off but in your case I would get it up towards 85% or so before killing the breaker so there's plenty of oomph left in the battery to kick up the heaters and still have enough to get you through the night if you show up later in the day. That 20% of the battery would be worth it if you have to heat up really cold batteries and then it gets cold out on top of that.

 

[Nan_wpg]

With these AIO units, if you turn the inverter off does it still pass through panel charging or is it all on, or all off?

im thinking AIO with the trophy battery. Battery can heat itself with solar current until its warm enough to charge.

this may all work

the lfp batteries with breakers, I noticed in wills video he connects the battery directly to the AIO. You’d still need a fuse right? Fuse protects wire. Breaker on battery just protects battery?

 

[littleharbor2]

With these AIO units, if you turn the inverter off does it still pass through panel charging or is it all on, or all off?

im thinking AIO with the trophy battery. Battery can heat itself with solar current until its warm enough to charge.

this may all work

the lfp batteries with breakers, I noticed in wills video he connects the battery directly to the AIO. You’d still need a fuse right? Fuse protects wire. Breaker on battery just protects battery?

I found out that, at least with Midnite Solar units, that the high max Voc units will stop PV charging when the inverter is turned off. The 3024 model with it's 100 Voc max PV input will keep charging the batteries unless you shut down PV input with a circuit breaker inline before the PV in of the AIO.

 

[Rednecktek]

With these AIO units, if you turn the inverter off does it still pass through panel charging or is it all on, or all off?

im thinking AIO with the trophy battery. Battery can heat itself with solar current until its warm enough to charge.

this may all work

the lfp batteries with breakers, I noticed in wills video he connects the battery directly to the AIO. You’d still need a fuse right? Fuse protects wire. Breaker on battery just protects battery?

I know the Growatts continue charging when the inverter is off and I believe the MPP's do as well. It's one of those things that hasn't been a regular review/test feature so you really need to find someone who has one and can run the test on their unit. We had a member on here run that test with his Growatt a while back and the SCC continued to plug along when the inverter was off. As the MPP and the Growatt are built by the same people and basically clones of each other I would guess the MPP's do the same thing.

 

[shampeon]

MPP Solar units also will charge with the inverter switch off.

Pretty sure Will’s setup has a big T class fuse from his busbar to the inverter.

 

[littleharbor2]

MPP Solar units also will charge with the inverter switch off.

Pretty sure Will’s setup has a big T class fuse from his busbar to the inverter.

Can you verify which model(s) will continue to charge? I'm curious if any high Voc. models will

 

[Nan_wpg]

So if I understand correctly:

1.LFP are not floated, they can be left over the winter (@50-80% charge) and they will be fine? Freezing won’t damage?
if so we use the solar during cabin season. Come close up, we disconnect PV, turn off inverter and anyone using cabin uses the generator.

2. If we want to use LFP in the winter (assuming MPP or growatt AIO, and trophy battery) we just continue as usual. The battery will heat itself with PV current and allow/not allow PV current to charge. turning the inverter on or off makes no difference.

3. Is it a good idea to leave inverter on or off when not using? If left on it could deplete battery (or battery shuts down on its own)?

remember, I need to keep it simple for stupid (me).

id hate to shell out 3600 bucks to find a dead battery come spring. LA is easy. Keep them full, and floated. That’s what current cottagers do. We’d be the first LFP on the lake.

side note: many cottagers have unhooked the ground from their systems. They claim it prevents lightning damage. Bad idea? Our current cabin wiring and genny is not grounded at all.

 

[SamDeleted]

Our current cabin wiring and genny is not grounded at all.

Eek

 

[MisterSandals]

side note: many cottagers have unhooked the ground from their systems. They claim it prevents lightning damage. Bad idea? Our current cabin wiring and genny is not grounded at all.

What do you consider "the ground"?

Some folks say "ground" (incorrectly in my book) when they talk about the negative battery wire.

 

[Nan_wpg]

Ground = grounding rod 8’ into the ground. Everything is connected to ground. The neutral is “bonded” to the ground somewhere in the system, and it can only bonded in one location only.

 

[Nan_wpg]

As I understand spd lightning protection devices they are connected to ground, and divert lightning to ground. But the cottagers that had blown inverters (even with spd) claim if you disconnect ground then lightning can’t get into the system. (Because theres a high iron content in the soil).

didn’t make sense to me. I don’t think anything is safe from a direct lightning hit

 

[shampeon]

Can you verify which model(s) will continue to charge? I'm curious if any high Voc. models will

LV-3048MK and the other LV models, but afaik all their models continue to allow the SCC to operate, and will charge the battery when on grid power if you have the settings correctly configured for that priority. The switch is only for the inverter circuit.

 

[shampeon]

So if I understand correctly:

1.LFP are not floated, they can be left over the winter (@50-80% charge) and they will be fine? Freezing won’t damage?
if so we use the solar during cabin season. Come close up, we disconnect PV, turn off inverter and anyone using cabin uses the generator.

Correct.

Though the AIO units we're talking about here have battery settings for LFP, so it won't float. So you can leave the PV connected and let the SCC in the inverter manage the battery SOC.

2. If we want to use LFP in the winter (assuming MPP or growatt AIO, and trophy battery) we just continue as usual. The battery will heat itself with PV current and allow/not allow PV current to charge. turning the inverter on or off makes no difference.

Correct. Only matters if you go through an extended period of no PV current (snow covered panels, overcast, etc.). The heater will drain some of the battery. Insulating the area around the battery is a good idea. Assuming there's enough sunlight to get the panels to wake up the SCC it should be fine.

3. Is it a good idea to leave inverter on or off when not using? If left on it could deplete battery (or battery shuts down on its own)?

Yes, it's a good idea to turn off the inverter when you leave. The idle consumption of the inverter is 30-100 watts, depending on the model. If you panel up to make sure you account for the idle consumption on your lowest performing months you can leave it on 24/7 but if you're sizing your system for spring, summer, and fall, just turn it off when after winterizing in the fall.

 

[Nan_wpg]

Correct.

Though the AIO units we're talking about here have battery settings for LFP, so it won't float. So you can leave the PV connected and let the SCC in the inverter manage the battery SOC.



Correct. Only matters if you go through an extended period of no PV current (snow covered panels, overcast, etc.). The heater will drain some of the battery. Insulating the area around the battery is a good idea. Assuming there's enough sunlight to get the panels to wake up the SCC it should be fine.



Yes, it's a good idea to turn off the inverter when you leave. The idle consumption of the inverter is 30-100 watts, depending on the model. If you panel up to make sure you account for the idle consumption on your lowest performing months you can leave it on 24/7 but if you're sizing your system for spring, summer, and fall, just turn it off when after winterizing in the fall.

if,going with #1 I don’t want any battery drain. (Cc may,drain battery if no sun?). The idea would be to completely disconnect pv from battery, turn off inverter and let battery sit for 6 months in the freezing cold.

 

[littleharbor2]

LV-3048MK and the other LV models, but afaik all their models continue to allow the SCC to operate, and will charge the battery when on grid power if you have the settings correctly configured for that priority. The switch is only for the inverter circuit.

The max voc. of the 3048 looks to be 115 vdc. I see the higher output inverters have up to 600 voc. Those are the ones I'm curious as to whether the PV charging shuts down with the inverter switched off.

 

[Nan_wpg]

How much power do the AIO‘s use? (If they are off do they use much?)

 

[MT_Mike]

As suggested figure out your daily power requirements first. You may want to consider a simple 30 or 50 amp rated RV charge controller which will support both 120VAC and 12VDC power distribution and battery charging when plugged into the generator. 200w - 400w solar panels and a charge controller and a 200AH Lipo4 battery. A 1500w/3000w (peak) inverter fed to an RV rated VAC change over box feeding the RV power distribution/charge controller will detect when shore power (generator) is on and will auto switch back to battery/inverter VAC. The 1500/3000w inverter will support the use of lower power 1000w travel hair dryer while on battery/inverter power. Provide a low power(1000w) travel hair dryer for folks to use and mark AC outlets accordingly. For your C-Pap I would use a separate battery or something like a 20AH/300 watt-hour portable Jackery power station you can charge with either 12VDC or 120VAC.

 

[Nan_wpg]

I will have to wait until October 2023 for a power audit. Kills watt on the genny, and hopefully everyone can keep a written record.

power usage will vary from nothing, to moderate use, to people staying up till 3am watching movies/starlink. I’ll take the absolute worst day of usage and plan around that. there’s nothing consistent.

No idea what a vac changeover box is.

I actually do currently use a portable power box for my cpap. It has a la battery, it’s heavy and a pain in the ass to bring back and forth to the cabin. That’s one of the main reasons for solar.

this cabin is remote, off grid, and honestly a pain in the ass. I’m trying to make this place suck a bit less so I can enjoy going out. Also hate hauling gas cans to and from.

I’ve decided against AIO. They use way too much power. Power saved is money not spent. I’m also not getting an inverter charger. I think it’s better to charge the battery with a seperate charge (hopefully won’t have to do this.)


No one uses a hair dryer at the cabin. The microwave gets used but it runs off the genny when the cabin is powered