Seller claims no date stamp on used Outback 3648 inverter. I suspect bs.

softdown

I asked about date that is normally stamped on the inverter. See pic.

Seller response:

"That’s sticker isn’t on mine for some reason. I had it install around this time in 21 brand new and pulled it out within the year and upgraded my system to 2 8 k wat inverters and more panels it’s bin on the shelf for about 2 years”

I am going lithium - already have them. Told that newer inverters work better with lithium than previous models. Unsure why - seems like charge controller territory? 

Perhaps they bought used as well? 

My inverter is heavily used so it could die within 2-3 years. Going without inverter is a giant hassle. New inverters are now quite expensive. Used inverters are usually pretty darned old. 

Price is right - $750. New - $2500 plus shipping

Kind of a tough call. What say more knowledgeable members?

I think the date sticker was removed. It is likely much older than claimed. 

New price went up a lot. Tough to swallow really. Nice equipment though.

JRHill

"I am going lithium - already have them. Told that newer inverters work better with lithium than previous models. Unsure why - seems like charge controller territory?"

The older VFX3648 inverters were fine with lead batteries. The new model VFXR3648A has adjustments that can accomodate and protect LFP04 batteries. The VFXR series allows for a higher low voltage cutout (LVCO) up to 54vdc where as the VFX was something like 49 which is way to low for LFP04. There are a few other benefits that are useful for off grid (support mode is a cool one) and other options for grid tie support.

I upgraded to the VFXR when I went with the SimpliPhi blocks. Be darned sure your vendor is selling you a VFXR3648A and not the older model.

As for the charge controller, the original FM80 purchased in 2010 is perfectly fine with adjustments to work LFP04 blocks.

softdown

That seems to indicate that lithium batteries operate at significantly higher voltage levels than lead. I have not used lithium.

Seems that a lithium bank would not operate properly with a lead bank. 

JRHill

softdown said:

That seems to indicate that lithium batteries operate at significantly higher voltage levels than lead. I have not used lithium.

Seems that a lithium bank would not operate properly with a lead bank. 

LFP04 batteries must have the manufacturer's recommended values programmed into the inverter and the charge controller so ya don't ruin the battery bank or shorten the lifespan. In general I think it is safe to say that both the upper limit for the bulk phase is a lower voltage and the low voltage cutoff is higher voltage than what you use for lead batteries. This one of the reasons that using the battery's voltage for State of Charge is so confusing for people used to lead batteries. It's just plain difficult to interpret the amount of charge remaining by voltage so that is why a battery monitor (like a Victron BMV) is almost essential. Fortunately the Victron is not very expense. And you have to set the monitor up and use it correctly or the info you get from it will be misleading or just plain wrong. But that's also true using a monitor with lead batteries too.

No, no, no: you never use lead and LFP04 together in the same system.

But I can say that in the almost 4 years of using the LFP04 batteries it's the closest I've ever been to having a maintenance free setup. And that has been a goal since the beginning because if something ever happened to me the wife could continue on just fine. Fueling and oil changes to the generator are about the only thing I have to do these days. I still fiddle with some things but that's because it is fun, for me anyway. But in actuality, little to nothing has to be done.

softdown

https://www.portablesolarexpert.com/the-best-solar-charge-controller-settings-for-lifepo4-batteries/

Some useful parameters and some, likely, nonsense. Lithium batteries do not balance until brought to a 100% SOC. 

I went deep into lithium 4 1/2 years ago. Even bought what is needed to make my own lithium battery banks. Yes, I over reacted to covid as it turned out. 

While forgetting most of what was learned I still remember enough to know that popular advice has changed in the past 4 1/2 years. Back then I figured that maintaining a charge rate between 20% and 80% would provide optimal battery life. Still would - IF one had the discipline to balance the battery cells on a regular basis. A rather big IF. Balanced battery cells are critical. 

Personally I’m not yet sold on lithium. While it does provide more cycling longevity it also cost a good deal more. Doesn’t handle freezing weather and currently seems more sensitive to temperatures over ~ 86F as well. Then we have the very occasional and possibly lethal fires to consider. 

Lithium is reliant on an on board BMS system and those go out periodically. There may be issues replacing the BMS board because the connective wiring system varies so widely. It is also currently more difficult to replace lithium batteries than lead batteries - unless one lives close to an urban supplier. I doubt that the local Tractor Supply or Big R carries much in the way of solar compatible lithium batteries. 

I’ll keep my other thoughts to myself in order to avoid being shouted down. 

littleharbor2

My experience with lithium batteries is a little different than yours apparently. I built probably 15 of them now As to active balancing, you can set the voltage point at which the balance starts so they don't need to remain at 100% to balance.
 They have a working temperature limit of 150°, then they began to experience damage. Also, LiFePO4, aka Lithium Iron Phosphate, are very safe and not prone to catching fire like some of the other lithium chemistries. 
 Changing out of BMS is something that Is not that big of a deal after you built a few batteries. It's very straightforward.
 Also 4 1/2 years down the road, referring to today, lithium has gotten quite a bit cheaper and you can build lithium batteries with double the capacity of lead acid for about the same price

Marc Kurth

What do you do with your old Lithium batteries when it's time to change them out?

littleharbor2

Not sure. I'll let you know in about 10 years, or so. 

softdown

littleharbor2 said:

My experience with lithium batteries is a little different than yours apparently. I built probably 15 of them now As to active balancing, you can set the voltage point at which the balance starts so they don't need to remain at 100% to balance.
 They have a working temperature limit of 150°, then they began to experience damage. Also, LiFePO4, aka Lithium Iron Phosphate, are very safe and not prone to catching fire like some of the other lithium chemistries. 
 Changing out of BMS is something that Is not that big of a deal after you built a few batteries. It's very straightforward.
 Also 4 1/2 years down the road, referring to today, lithium has gotten quite a bit cheaper and you can build lithium batteries with double the capacity of lead acid for about the same price

I have no real experience with solar lithium batteries. Just what I glean from reading and watching podcasts. Good to know that balancing can be set at less than a 100% charge. How is that done? More sophisticated balancing boards perhaps? 

The freezing parameters continue to concern me. This is Colorado’s coldest region. It is 31 degrees in the unheated area of this home. Just wait until January and February. 

"Changing out of BMS is something that Is not that big of a deal after you built a few batteries. It's very straightforward.”    I wonder what percentage will ever build lithium batteries. Thought I was going to at one time. 

littleharbor2

I find building them good therapy. Keeps the mind sharp. 
 Cell balancing can be set to continually balance, or at whatever setpoint you choose in the Bluetooth app settings. Very simple settings.

JRHill

I learned last week that my SimpliPhi blocks can balance @ 55.6 and up which works out perfectly, at least for me with OEM blocks that are 'is what it is' out of the box. All yall have probably figured out that I will never go back to lead (knock on wood).

softdown

JRHill said:

I learned last week that my SimpliPhi blocks can balance @ 55.6 and up which works out perfectly, at least for me with OEM blocks that are 'is what it is' out of the box. All yall have probably figured out that I will never go back to lead (knock on wood).

Balancing at 55.6? Nice!

softdown

littleharbor2 said:

I find building them good therapy. Keeps the mind sharp. 
 Cell balancing can be set to continually balance, or at whatever setpoint you choose in the Bluetooth app settings. Very simple settings.

Victron BMV cost ~$100 more than some alternatives. Noted difference is the bluetooth feature found in the Victron. Can you set your balance voltage via your BMV? Is it a Victron by chance? 

If not your BMV then what???

softdown

Seller sold the Outback. I just didn’t feel like driving for 5 hours plus in the mountains to get it. Icy hill corners can ruin your whole day. Plus they “upgraded" to two 8 kW inverters. Indicating a distinct possibility that the Outback didn’t live up to their needs. In the meantime it was likely “over revving” - hard on the unit for sure. 

Nevertheless I hoped to pick it up on my next trip to Denver. Whenever that might be. The price was right for a back up unit. Though “no warranty” is pause for concern. It might be broken. 

JRHill

softdown said:

littleharbor2 said:

I find building them good therapy. Keeps the mind sharp. 
 Cell balancing can be set to continually balance, or at whatever setpoint you choose in the Bluetooth app settings. Very simple settings.

Victron BMV cost ~$100 more than some alternatives. Noted difference is the bluetooth feature found in the Victron. Can you set your balance voltage via your BMV? Is it a Victron by chance? 

If not your BMV then what???

$158 list from NAZ and I saw them as low as $110. Yup, I have the BMV-712 Smart and love it. I can't adjust anything in the batteries and frankly there is no need. I charge 4 Phi blocks to 55.6 with 12 minutes of Absorb. I start the 100% SOC countdown from there and usually don't go below 65%.

JRHill

softdown said:

Seller sold the Outback. I just didn’t feel like driving for 5 hours plus in the mountains to get it. Icy hill corners can ruin your whole day. Plus they “upgraded" to two 8 kW inverters. Indicating a distinct possibility that the Outback didn’t live up to their needs. In the meantime it was likely “over revving” - hard on the unit for sure. 

Nevertheless I hoped to pick it up on my next trip to Denver. Whenever that might be. The price was right for a back up unit. Though “no warranty” is pause for concern. It might be broken. 

I bought a replacement new in box VFXR3648A from NAZ recently for a spare while they are still available. It was a $ hit but it is the first thing I've done in the way of a spare anything. I justified it as a Christmas present to the homestead project. As things are going with Outback it may be like money in the bank. Hopefully I'll never need it and I'll take bets it won't lose value.

littleharbor2

softdown said:

littleharbor2 said:

I find building them good therapy. Keeps the mind sharp. 
 Cell balancing can be set to continually balance, or at whatever setpoint you choose in the Bluetooth app settings. Very simple settings.

Victron BMV cost ~$100 more than some alternatives. Noted difference is the bluetooth feature found in the Victron. Can you set your balance voltage via your BMV? Is it a Victron by chance? 

If not your BMV then what???

I have a Bogart trimetric battery monitor I just use that to monitor the status of my battery. The BMS is part of the lithium battery build and that's where all the settings are done

JRHill

We all take different paths for the outcome desired. If someone has to follow behind you can they figure it out? Is there detailed documentation?

softdown

littleharbor2 said:

softdown said:

littleharbor2 said:

I find building them good therapy. Keeps the mind sharp. 
 Cell balancing can be set to continually balance, or at whatever setpoint you choose in the Bluetooth app settings. Very simple settings.

Victron BMV cost ~$100 more than some alternatives. Noted difference is the bluetooth feature found in the Victron. Can you set your balance voltage via your BMV? Is it a Victron by chance? 

If not your BMV then what???

I have a Bogart trimetric battery monitor I just use that to monitor the status of my battery. The BMS is part of the lithium battery build and that's where all the settings are done

Building it all yourself is admirable of course. But I doubt that many of us will get around to that level of battery skills. 

At 66 I am starting to think in terms of 10-15 years. My cell balancers are about as simple as they come I think. I don’t see how they could be programmed to start working at a certain level - such as 55.6.

softdown

JRHill said:

softdown said:

Seller sold the Outback. I just didn’t feel like driving for 5 hours plus in the mountains to get it. Icy hill corners can ruin your whole day. Plus they “upgraded" to two 8 kW inverters. Indicating a distinct possibility that the Outback didn’t live up to their needs. In the meantime it was likely “over revving” - hard on the unit for sure. 

Nevertheless I hoped to pick it up on my next trip to Denver. Whenever that might be. The price was right for a back up unit. Though “no warranty” is pause for concern. It might be broken. 

I bought a replacement new in box VFXR3648A from NAZ recently for a spare while they are still available. It was a $ hit but it is the first thing I've done in the way of a spare anything. I justified it as a Christmas present to the homestead project. As things are going with Outback it may be like money in the bank. Hopefully I'll never need it and I'll take bets it won't lose value.

Seem to be saying that we will not be able to replace our VFXR3648s. Since I have the Flex Power system that would be a huge setback.

JRHill

I'm not saying that but I am (not) betting on it. Think SolarKings. Put your best configuration together and wager. Who will win this season and who will exist to the next season? Who are the best players?

I can't officially say this but I love *****Kings. They made me a bunch of money in sales commissions for technology. This is now used on you if you are stupid enough to play the game. Sorry. Go buy a lottery ticket. 6 of one and half dozen of another. Go give your money away and to State taxes. One day you'll hit the big one.

Or quit the game.

littleharbor2

softdown said:

littleharbor2 said:

softdown said:

littleharbor2 said:

I find building them good therapy. Keeps the mind sharp. 
 Cell balancing can be set to continually balance, or at whatever setpoint you choose in the Bluetooth app settings. Very simple settings.

Victron BMV cost ~$100 more than some alternatives. Noted difference is the bluetooth feature found in the Victron. Can you set your balance voltage via your BMV? Is it a Victron by chance? 

If not your BMV then what???

I have a Bogart trimetric battery monitor I just use that to monitor the status of my battery. The BMS is part of the lithium battery build and that's where all the settings are done

Building it all yourself is admirable of course. But I doubt that many of us will get around to that level of battery skills. 

At 66 I am starting to think in terms of 10-15 years. My cell balancers are about as simple as they come I think. I don’t see how they could be programmed to start working at a certain level - such as 55.6.

That is a stand alone cell balancer. A BMS with active balance function is what I use and they are fully programmable. If you can wire up a balancer, you could just as easily wire up a BMS.