Seplos Mason DIY kit review (4/5)

[Sanwizard]

Adam mentioned the 2amp active balancer board (which is optional extra) is still in testing (this was on 15 Jul 2023)

I am fairly excited about the module, as it would really fill in a major flaw (In my opinion) in the existing design, and make me more comfortable in setting and forgetting the batteries. Nobody should have to monitor and babysit a freaking battery.

 

[houseofancients]

I am fairly excited about the module, as it would really fill in a major flaw (In my opinion) in the existing design, and make me more comfortable in setting and forgetting the batteries. Nobody should have to monitor and babysit a freaking battery.

Agreed, and it would be extra sweet if it could be used of the 10e version, as it is an add-on.
We'll see when they release it

 

[Grend]

Hi,
I am just about to order my Seplos kit and 280Ah A grade cells - I like the idea of two screws per terminal. Just a couple of questions.

I see the bus bars are aluminium but copper ones are available as an extra. They are flexible as they are made of multi-layer copper. Now I like the idea of them being flexible to reduce the strain on the terminals, and bulk copper has a lower resistivity than aluminium, but would the fact that they are multi-layer increase the chance of corrosion and for that matter increase the overall resistivity ?

Improved Busbars for Grade A 280Ah/304Ah LiFePO4 Cells

Flexible multi-layer copper busbars ideal for use with our Grade A 304ah LiFePO4 cells. Each shipped pack contains; four (4) flexible copper busbars and sixteen (16) M8 fixing screws. Next Day Delivery. UK Stockist.

www.fogstar.co.uk

Is there any guidance as to the order for connecting up the BMS? Black and white plugs before the main + and -? or - first?

I have not seen the Futronics connectors in the flesh but I am concerned about any plug / socket carrying 100A. I see there is a wide range of four hole fixing bulkhead mounted feed throughs that would provide a bolt on the inside AND the outside for the cable connection. Am I over thinking all this?

Does the BMS regulate the charge voltage or is it just a cut-off? I am thinking once the battery is assembled using a bench power supply to trickle charge the pack but does my power supply have to be at exactly 57.6v (or what ever)? I would be happier to do a slow charge and discharge first to make sure all is well.

 

[Sanwizard]

Hi,
I am just about to order my Seplos kit and 280Ah A grade cells - I like the idea of two screws per terminal. Just a couple of questions.

I see the bus bars are aluminium but copper ones are available as an extra. They are flexible as they are made of multi-layer copper. Now I like the idea of them being flexible to reduce the strain on the terminals, and bulk copper has a lower resistivity than aluminium, but would the fact that they are multi-layer increase the chance of corrosion and for that matter increase the overall resistivity ?

Improved Busbars for Grade A 280Ah/304Ah LiFePO4 Cells

Flexible multi-layer copper busbars ideal for use with our Grade A 304ah LiFePO4 cells. Each shipped pack contains; four (4) flexible copper busbars and sixteen (16) M8 fixing screws. Next Day Delivery. UK Stockist.

www.fogstar.co.uk

Is there any guidance as to the order for connecting up the BMS? Black and white plugs before the main + and -? or - first?

I have not seen the Futronics connectors in the flesh but I am concerned about any plug / socket carrying 100A. I see there is a wide range of four hole fixing bulkhead mounted feed throughs that would provide a bolt on the inside AND the outside for the cable connection. Am I over thinking all this?

Does the BMS regulate the charge voltage or is it just a cut-off? I am thinking once the battery is assembled using a bench power supply to trickle charge the pack but does my power supply have to be at exactly 57.6v (or what ever)? I would be happier to do a slow charge and discharge first to make sure all is well.

You need to top balance the cells. The copper bus bars are better in my opinion, but not sure how much it matters, because the terminals are aluminum.

I did the black and white cables connected to the battery side first, and checked that the voltage order was correct before connecting them to the BMS, but that said, the build is so easy and brain dead simple, its hard to screw it up.
Order the futronics connectors with the battery, since they are a bitch to find in the US. They handle the current fine.

When the comms are connected, the BMS regulates the charge current in coordination with the inverter, but I dont use comms. I have seven Masons in parallel, (a mix of 280ah and 135ah) and once the bulk voltage is hit, the BMS drops the current in that battery. The others continue to charge until they all balance out to the same voltage.

The SOC of each battery may be slightly different, but you can use a 48V charger to make up the difference if you wish.

 

[GuyG]

The case is also built like a bomb shelter.

Anyone with a Seplos Mason 280 case: What gauge steel do they use? 16? 14? Thicker?

 

[Sanwizard]

Anyone with a Seplos Mason 280 case: What gauge steel do they use? 16? 14? Thicker?

I am not a metal expert, but I would say around 12 gauge or better. They are heavy and well welded. Zero flex. When cells are added, you need a lift or at least two strong men to lift it.
I built a rack for them using Unistrut, cause stacking them negates the ability to get to the cells for maintenance.
I have mine outdoors, so I also needee to build a waterproof frame around them. So far so good, even after a major storm.

 

[GuyG]

Thanks. If anyone who has one of these boxes ever puts a caliper on one, I’d be real interested to know what they measure.

 

[mr-k]

Hi all, I bought a seplos mason 280 kit with the grade a 280 cells, I have top balanced the cells, they are currently sitting at 3.6v, have put them into the case and compressed them as specified, i assume i need to let them drop down to approx 3.3v before connecting them to the bms, is that correct

 

[houseofancients]

Hi all, I bought a seplos mason 280 kit with the grade a 280 cells, I have top balanced the cells, they are currently sitting at 3.6v, have put them into the case and compressed them as specified, i assume i need to let them drop down to approx 3.3v before connecting them to the bms, is that correct

you can connect them straight away...
please do remember you need to "train" the bms...
in order to do so : after you connected the bms...

charge the pack until bms cut off, then discharge to bms cut off...
at that point the bms will be trained, and you can charge/use them as you would normally

 

[mr-k]

you can connect them straight away...
please do remember you need to "train" the bms...
in order to do so : after you connected the bms...

charge the pack until bms cut off, then discharge to bms cut off...
at that point the bms will be trained, and you can charge/use them as you would normally

Hi, if the cells are at 3.6v that gives a total of 57.6 volts, wont that damage the bms, will i get an over voltage alarm, and thanks for the response

 

[houseofancients]

Hi, if the cells are at 3.6v that gives a total of 57.6 volts, wont that damage the bms, will i get an over voltage alarm, and thanks for the response

no it will not hurt your bms...
by default high cell disconnect ( which is the trigger to start the calibration process ) is by default set to 57.8 ( 3.65v per cell)

after calibration, make sure you set the high voltage disconnect (= charge voltage used if using CANBUS) to a lower and more acceptable value .. ( i use 56.8 but there are many more opions and values to be found on the forum )

 

[Sanwizard]

Hi, if the cells are at 3.6v that gives a total of 57.6 volts, wont that damage the bms, will i get an over voltage alarm, and thanks for the response

3.65 is the max for LiFePo4 cells. Once one of the cells reach that, rh3 BMS will protect the cells and disable charging, and set the over voltage alarm. That should trigger the BMS to 100% charge. No, it will not damage the BMS. Follow @houseofancients instructions.

 

[mr-k]

Hi both, thanks for the advice, connected the cells to the bms and its giving an over voltage warning, unfortunately i cant get my pc to communicate with the bms

i am using devbmsstudio from seplos and a cable supplied by fogstar,

 

[mr-k]

i get a message that reads - bms response error - length error

 

[Sanwizard]

i get a message that reads - bms response error - length error

Use the Battery Monitor software with an RS485 to USB cable to connect and change parameters on the BMS. There is a PC version and I believe now an Android version.

BMS software download - Seplos Technology

Seplos Technology, with resources for solar battery, home energy storage, bms software free to download.

www.seplos.com

 

[Sanwizard]

Use the Battery Monitor software with an RS485 to USB cable to connect and change parameters on the BMS. There is a PC version and I believe now an Android version.

BMS software download - Seplos Technology

Seplos Technology, with resources for solar battery, home energy storage, bms software free to download.

www.seplos.com

Which BMS version do you have? I believe the studio software is for BMS version 3. Battery monitor is for BMS version 1 and 2.

 

[houseofancients]

i get a message that reads - bms response error - length error

If usi g the V2 version, use battery monitor and an usb to rs485 adapter.
Most likely your BMS has a bluetooth available..


You can download the Android app from the seplos site

BMS software download - Seplos Technology

Seplos Technology, with resources for solar battery, home energy storage, bms software free to download.

www.seplos.com

 

[mr-k]

hi, not 100% sure on the bms version, i purchased the kit about 4 weeks ago, i bought the cable at the same time, i downloaded the software and thats the error that i get, going to get our android tablet charged and try it with blue tooth, also going to wat the off grid garage videos cos i am am sure that he had an issue connecting via a cable .

 

[houseofancients]

hi, not 100% sure on the bms version, i purchased the kit about 4 weeks ago, i bought the cable at the same time, i downloaded the software and thats the error that i get, going to get our android tablet charged and try it with blue tooth, also going to wat the off grid garage videos cos i am am sure that he had an issue connecting via a cable .

Can you post a picture of your box, and if possible of the BMS ?

 

[Misant]

anyone know which aerosol fire extinguisher can connect to nr 14?
I asked Seplos on Aliexpress but i got the reply thy dont know what an aerosol fire system is...