Seplos Mason DIY kit review (4/5)

[houseofancients]

For teaching cut offs, do you leave the bms defaults for both high and low? I can't remember what I did for my first two batteries, but I know I lowered the charge below default after setting up. will be setting up a third battery soon.

I do, as they are individual cell protections, however, my inverters are set to never go below 15% , so the cells do not go below ~ 3.0v .
That is fine by me, as it will prologongue cell life.

Upon reaching the charge voltage, the BMS will reset to 100% after 1 hour, so that is effectively the absorption time, inverter will limit charging to 10a ( send by BMS comms) at 98% so balancing has plenty of time, if you have done initial top balancing.
Because I have envision a- cells I did add a neey 4a active balancer, but so far they have not run since the initial balancing when box was taking " in production " .

Again, there are folks that use different settings on the forum, but this has worked best for me

 

[Sanwizard]

For teaching cut offs, do you leave the bms defaults for both high and low? I can't remember what I did for my first two batteries, but I know I lowered the charge below default after setting up. will be setting up a third battery soon.

In order to have the BMS determine the correct AH rating for your cells, you should leave the LiFePo4 cell defaults (usually 3.65v and 2.5v).

Most of the cells being sold are grade B, so a 280ah may only actually get around 270ah in practice. Its also good practice after you teach the BMS to set the voltage range to around 80-90%. I set mine to bulk charge a 16S pack to 56V, and float at 54.2V.

 

[mr-k]

You'll be fine with 50mm..
Just make sure you do not exceed 100a draw out of the battery..
Should you need more, add batteries...

Second option is replacing the connectors all together.

Look at amphenol , most readily available

You'll be fine with 50mm..
Just make sure you do not exceed 100a draw out of the battery..
Should you need more, add batteries...

Second option is replacing the connectors all together.

Look at amphenol , most readily available

Hi, i am going to do as you say and use a suitably sized fuse in the mersen

 

[mr-k]

Hi, I am discharging my seplos 280kit for the first time to train the BMS, how low should i let the SOC go,

 

[Sanwizard]

Hi, I am discharging my seplos 280kit for the first time to train the BMS, how low should i let the SOC go,

Till the BMS turns off discharge

 

[mr-k]

Sorry state of capacity, ive modified the settings in the bms for this to be 3%, is that too low?

 

[Sanwizard]

Sorry state of capacity, ive modified the settings in the bms for this to be 3%, is that too low?

BMS should he 3.65V MAX, and 2.5V MIN.
Once the BMS learns your true capacity, then set the charge/discharge to around 80-90%, depending on your needs. I have my bulk set to 56V, and my float to 54.2V. And 48V stop discharge.
Watch a few of Andy's earlier videos on charge curves and set yours how you like.
Andy is at offgridgarage youtube channel.

 

[mr-k]

BMS should he 3.65V MAX, and 2.5V MIN.
Once the BMS learns your true capacity, then set the charge/discharge to around 80-90%, depending on your needs. I have my bulk set to 56V, and my float to 54.2V. And 48V stop discharge.
Watch a few of Andy's earlier videos on charge curves and set yours how you like.
Andy is at offgridgarage youtube channel.

Andys videos were one of the reasons i went with the seplos mason kit, i wish i had bought or 2 sooner rather than going down the pylontech route, not sure what i am going to do with the pylontech batteries now, anyhow i watched that video where he trains the mason kit bms and have set all the settings to what he advises, i can change the pack remaining capacity to 2.5% as he advises, and save the changes, but when i go back in it has gone to 2% so i have set it at 3%

 

[MisterB1959]

Andys videos were one of the reasons i went with the seplos mason kit, i wish i had bought or 2 sooner rather than going down the pylontech route, not sure what i am going to do with the pylontech batteries now, anyhow i watched that video where he trains the mason kit bms and have set all the settings to what he advises, i can change the pack remaining capacity to 2.5% as he advises, and save the changes, but when i go back in it has gone to 2% so i have set it at 3%

I'm sure you could sell the pylontech batteries. I have a similar dilemma (in the UK) I am thinking of replacing my single 14.3kw A grade EVE cells upright Seplos 280L with a 2x different batteries .... I want to do it but the sums don't really add up !

 

[houseofancients]

I'm sure you could sell the pylontech batteries. I have a similar dilemma (in the UK) I am thinking of replacing my single 14.3kw A grade EVE cells upright Seplos 280L with a 2x different batteries .... I want to do it but the sums don't really add up !

Why not buy a seplos diy 280 kit and use you cells in that ?
Seems silly not to use those cells

 

[mr-k]

Why not buy a seplos diy 280 kit and use you cells in that ?
Seems silly not to use those cells

The pylotech use a 15s setup and they use pouch cells, i dont want to break them down into individual components


I could try to rotate the use between the pylontech and the seplos mason 280. So charge one whilst discharging the other, its just ive set the max charge for the pylontech at 51.8v so if I do keep both types of batteries then everytime I changed them over i would have to change the settings in the mppt(s) and the inverter or the higher charge rate of the seplos would blow the bms of the pylontech. I think that in the victron mppt you can create your own battery preset perhaps that would help

I do have another inverter, its a 48/3000 multiplus, another option i was considering was getting an energy tariff that offers a low rate and using the pylontech(s) and that to take power from the grid and use it when the price is more expensive,

I dont power the whole house from the batteries and we have a separate consumer unit for the battery circuits, but if i sell the 4 pylontech i bet i will lose around £300 on each one, so perhaps swapping when needed is the answer

 

[houseofancients]

The pylotech use a 15s setup and they use pouch cells, i dont want to break them down into individual components


I could try to rotate the use between the pylontech and the seplos mason 280. So charge one whilst discharging the other, its just ive set the max charge for the pylontech at 51.8v so if I do keep both types of batteries then everytime I changed them over i would have to change the settings in the mppt(s) and the inverter or the higher charge rate of the seplos would blow the bms of the pylontech. I think that in the victron mppt you can create your own battery preset perhaps that would help

I do have another inverter, its a 48/3000 multiplus, another option i was considering was getting an energy tariff that offers a low rate and using the pylontech(s) and that to take power from the grid and use it when the price is more expensive,

I dont power the whole house from the batteries and we have a separate consumer unit for the battery circuits, but if i sell the 4 pylontech i bet i will lose around £300 on each one, so perhaps swapping when needed is the answer

Wasn't regering to you rather @MisterB1959

 

[Sanwizard]

Andys videos were one of the reasons i went with the seplos mason kit, i wish i had bought or 2 sooner rather than going down the pylontech route, not sure what i am going to do with the pylontech batteries now, anyhow i watched that video where he trains the mason kit bms and have set all the settings to what he advises, i can change the pack remaining capacity to 2.5% as he advises, and save the changes, but when i go back in it has gone to 2% so i have set it at 3%

I dont remember his handle, but Seplos developed the Mason kits based on a person from this forum. He paid the upfront development costs for the Mason idea. Its in one of the threads.

I was pretty lucky that I bought 4 of the 135AH Masons packs which included the cells during Seplos initial offering to drum up business. They put them on sale for $1000 US each plus shipping, so the 4 came to about $4400 all in. They seem to be grade A cells too, since they stay fairly tight from a balancing perspective.

I feel like you that I should have bought more at that time.
As for your Pylontech batteries, I would hold on to them. Pylontech is a leader in their field, as it seems many BMS and Inverter manufacturers seem to fall back on the pylontech protocol as a standard, and they have a pretty good cycle count life.

 

[MisterB1959]

Why not buy a seplos diy 280 kit and use you cells in that ?
Seems silly not to use those cells

i have a Seplos 280L already and was thinking of passing it on and getting two other batteries - i think you may have confused what i meant !

 

[Sanwizard]

i have a Seplos 280L already and was thinking of passing it on and getting two other batteries - i think you may have confused what i meant !

Ah.. what do you not like about the 280L, any specific issues?

 

[mr-k]

I dont remember his handle, but Seplos developed the Mason kits based on a person from this forum. He paid the upfront development costs for the Mason idea. Its in one of the threads.

I was pretty lucky that I bought 4 of the 135AH Masons packs which included the cells during Seplos initial offering to drum up business. They put them on sale for $1000 US each plus shipping, so the 4 came to about $4400 all in. They seem to be grade A cells too, since they stay fairly tight from a balancing perspective.

I feel like you that I should have bought more at that time.
As for your Pylontech batteries, I would hold on to them. Pylontech is a leader in their field, as it seems many BMS and Inverter manufacturers seem to fall back on the pylontech protocol as a standard, and they have a pretty good cycle count life.

Looking into the options, solar pv isnt brilliant here in the uk, so does anyone know, would it be practical to have 2 separate battery banks, one charged from solar, part of the the ac ouput of that banks inverter used as the ac input to charge the other bank via inverter 2, i could then use one bank for my office and the other for our kitchen, just thinking aloud at the moment, we arent off grid so mains is still available

 

[houseofancients]

Looking into the options, solar pv isnt brilliant here in the uk, so does anyone know, would it be practical to have 2 separate battery banks, one charged from solar, part of the the ac ouput of that banks inverter used as the ac input to charge the other bank via inverter 2, i could then use one bank for my office and the other for our kitchen, just thinking aloud at the moment, we arent off grid so mains is still available

Not really, what you are looking for is a hybrid, since you are in the UK, I'd look at Sunsynk ( but I am biast )

Allows you to charge from ac, charge from DC ( solar/wind/hydro) and send back to grid when overproducing in summer, all from the same battery bank ( seplos in my case), I am in Holland btw
And.. fully certified in the uk

 

[MisterB1959]

Ah.. what do you not like about the 280L, any specific issues?

The only thing I don't like, and it's personal opinion, is the lack of automatic heater and pad etc. on the basis that it's in an unheated area. Other than that it has performed brilliantly, no issues whatsoever! I have now built (almost) an insulated cover and added an external heating pad, which would be brilliant BUT it now sticks out of the cupboard I have it in and I can't close the door.......
If you're siting it indoors, in a heated area then I'm not so sure you could get a nicer looking battery!
I would highly recommend the Seplos 280L but also suggest that anyone considering it also should also order the internal heat pad !!

 

[MisterB1959]

Looking into the options, solar pv isnt brilliant here in the uk, so does anyone know, would it be practical to have 2 separate battery banks, one charged from solar, part of the the ac ouput of that banks inverter used as the ac input to charge the other bank via inverter 2, i could then use one bank for my office and the other for our kitchen, just thinking aloud at the moment, we arent off grid so mains is still available

Not sure what you're trying to achieve? With a hybrid it can take PV and charge from the mains, so you only need one inverter.
I have an existing PV system installed under the Feed in Tariff scheme. So I have one inverter that is grid tied and one hybrid inverter. I actually could just use the hybrid inverter BUT I would then lose my FiT payments.

PS my hybrid is also a Sunsynk. I originally had a Sofar but it had a low charge rate of 3.6kw so I was lucky enough to pick up a very well (cheap) priced Sunsynk 5kw, though I would have been better with an 8Kw in hindsight but the smaller 5kw was too good to miss! I could add another 5kw and it would work out at roughly the cost of one 8kw if I really need it in the future.

 

[Sanwizard]

The only thing I don't like, and it's personal opinion, is the lack of automatic heater and pad etc. on the basis that it's in an unheated area. Other than that it has performed brilliantly, no issues whatsoever! I have now built (almost) an insulated cover and added an external heating pad, which would be brilliant BUT it now sticks out of the cupboard I have it in and I can't close the door.......
If you're siting it indoors, in a heated area then I'm not so sure you could get a nicer looking battery!
I would highly recommend the Seplos 280L but also suggest that anyone considering it also should also order the internal heat pad !!

You can always add a FACON pad with internal thermostat. Just use a buck converter to get the 48V down to 12V, and stick the pad on the inside cover. Badda bing, 70w of gentle heat keeping the cells nice and toasty.

https://www.amazon.com/Facon-Holding-Motorhome-Automatic-Thermostat/dp/B07GW8ZX7X/ref=asc_df_B07GW8ZX7X&mcid=93840dbcd7813aac86811d8f9128a735?tag=bngsmtphsnus-20&linkCode=df0&hvadid=79920869053493&hvnetw=s&hvqmt=e&hvbmt=be&hvdev=m&hvlocint=&hvlocphy=&hvtargid=pla-4583520402462817&psc=1