Joining the Renewable Heating Hub forums is completely free and only takes a minute. By registering you’ll be able to ask questions, join discussions, follow topics you’re interested in, bookmark useful threads and receive notifications when someone replies. Non-registered members also do not have access to our AI features. When choosing your username, please note that it cannot be changed later, so we recommend avoiding brand or product names. Before registering, please take a moment to read the Forum Rules & Terms of Use so we can keep the community helpful, respectful and informative for everyone. Thanks for joining!
@makia2023 I hooked up the cell monitoring lines before connecting the B+ cable (circled red) from the pack to the BMS. After about 2 mins I noticed the telltale smell of hot conformal coating coming from the area around the balance resistors (circled green).
Seplos V3 has the shunts in the -ve bus, unlike V2 which had a separate shunt onboard in the +ve bus, hence the need for a bat+ sense wire.
The BMS powers up fine but it reads 0mV for all the cell voltages. It reads the pack voltage correctly however.
I think I'll order a replacement from fogstar, I could swap my batrium over from my 9.6kWh pack, but it's very much not reliable, and it would be some work to make it all fit.
Off grid on the isle of purbeck
2.4kW solar, 15kWh Seplos Mason, Outback power systems 3kW inverter/charger, solid fuel heating with air/air for shoulder months, 10 acres of heathland/woods.
My wife’s house: 1946 3 bed end of terrace in Somerset, ASHP with rads + UFH, triple glazed, retrofit IWI in troublesome rooms, small rear extension.
Save energy... recycle electrons!
@transparent The seplos v3 is the standard passive balancing BMS, their 'active balancer' is a separate unit that connects via an additional harness, directly to the cells. It is non-programmable, and works at any cell voltage >3V, when there is a 50mV delta.
It's generally considered to be 'a bit junk', as it's not programmable and can't be enabled only at >3.45V/cell.
Off grid on the isle of purbeck
2.4kW solar, 15kWh Seplos Mason, Outback power systems 3kW inverter/charger, solid fuel heating with air/air for shoulder months, 10 acres of heathland/woods.
My wife’s house: 1946 3 bed end of terrace in Somerset, ASHP with rads + UFH, triple glazed, retrofit IWI in troublesome rooms, small rear extension.
@Transparent - as it will be set low AND should be fed using the electricity from the battery, then i thought it was a reasonable option, especially if i insulated the heating pad and rear of the Seplos with a couple of inches of celotex or similar.
@Makia2023 - i did consider something similar but decided against it as i wanted to stop the battery from dropping below charging levels, as opposed to heating the immediate are its in.
New bms delivered today from fogstar, all installed and up and running 👍
Now to find that 3kW charger I’ve got somewhere….
Off grid on the isle of purbeck
2.4kW solar, 15kWh Seplos Mason, Outback power systems 3kW inverter/charger, solid fuel heating with air/air for shoulder months, 10 acres of heathland/woods.
My wife’s house: 1946 3 bed end of terrace in Somerset, ASHP with rads + UFH, triple glazed, retrofit IWI in troublesome rooms, small rear extension.
Expand that comment please @makia2023
The full SunSynk diagram of all possible configurations has three CTs on it. 🙄
I'm going to assume that you're referring to the one which connects to positions 5 & 6 on the Inverter, and has the clamp/transformer around the live feed wire between the inverter and its mcb-trip in your consumer unit.
In the manual, you probably have this diagram, and will have read the comments below and to the right:
See also the table at the bottom of the following page.
Although it's beneath the diagram which covers installation in the USA, it's still relevant.
What reading do you get if you disconnect the CT-clamp wires from the inverter, and use a multimeter set to ohms?
Save energy... recycle electrons!
Having more than one multimeter would seem a prudent investment for someone who's just imported 64 lithium cells from China!
I have three multimeters, one 'mains tester' box and an assortment of dedicated current/voltage meters.
And yes, I have needed to use all of them simultaneously on one occasion!
I've just checked online, and Amazon have at least 50 multimeter models, auto-ranging, at less than £30 and available for delivery on Saturday!
Give yourself an 'essential' Christmas present.
Save energy... recycle electrons!
I have a spare. I'm getting no reading from either my old or new ct clamp with it. Any thoughts?
I'm tempted to run another cat 6 cable separately and see if that works. But will be a tomorrow thing. I'm stumped.
It should definitely see the grid load regardless of battery system/solar right?
- 26 Forums
- 2,590 Topics
- 60.3 K Posts
- 333 Online
- 6,922 Members
Join Us!
Worth Watching
Latest Posts
-
RE: Octopus Cosy Heat Pump Owners & Discussion Thread
@agentgeorge I'll give it a go with my Apple Watch late...
By HarrisonC , 50 minutes ago
-
RE: Air-to-air heat pumps - best models and installers
Are you creating a whole new category for A2A?
By ASHP-BOBBA , 4 hours ago
-
RE: A2A vs A2W: Which Heat Pump Would You Pick?
There isn’t as far as I know, @djh, but you’re welcome ...
By Majordennisbloodnok , 16 hours ago
-
RE: Can anyone explain the following behaviour with a Grant Aerona 3 R30 / Smart Controller?
Final Update. Yesterday, I was going through the moti...
By Unsure , 18 hours ago
-
RE: How much can an east/west solar solar system be oversized?
Best performance occurs with PV string near inverter no...
By bobflux , 18 hours ago
-
RE: Forum updates, announcements & issues
Thank you Mars for all your dedication to improvements;...
By Toodles , 21 hours ago
-
RE: Who do I complain to about a poor ECO4 installation, can anyone advise?
Take it one step at a time. If you can get the dhw and...
By JamesPa , 1 day ago
-
RE: Selling 2 x Kensa Shoebox 7kw GSHP (New)
Hi Jain, we’ve got an ashp so I’m afraid we won’t be yo...
By Judith , 1 day ago
-
No buffer or low loss header Grant controller in sens...
By JamesPa , 2 days ago
-
RE: Are We Sleepwalking Into Another Race to the Bottom?
That's an amazing job to get all that in there! A truly...
By Batpred , 2 days ago
-
RE: Anyone concerned about GivEnergy?
Thanks for your advice - I'll keep trying with the inst...
By JohnDwyer , 2 days ago
-
RE: Plug and play solar. Thoughts?
I am also yet to find a case where an installation that...
By Batpred , 2 days ago
-
RE: British Gas vs Octopus Energy vs Heat Geek vs EDF vs Aira vs OVO vs EON.Next vs Boxt
This is what I got from OVO. At least it was quick.. ...
By Batpred , 2 days ago
-
RE: IVT greenline HT Plus E - Circulation Pump Constantly On
Welcome to the forums. Irrespective of which brand yo...
By Mars , 3 days ago
-
RE: 7.5kW Heat Loss, But Quoted a 10kW Midea. No Re-Pipe, No Buffer Tank. Does This Add Up?
Oh, how I love these old scientists!I'm in with your 5 ...
By LeJamaisContent , 3 days ago
-
RE: Jokes and fun posts about heat pumps and renewables
@jamespa Someone who is not easily phased I suppose.
By Toodles , 3 days ago
-
@downfield Once OE had removed our gas meter and capped...
By Toodles , 3 days ago
-
Living with a Low Loss Header (Or Measure For Measure, it’s All About the Pump)
I know, low loss headers (LLHs) aren’t necessarily ‘low...
By Toodles , 3 days ago
-
RE: What is the main ‘dictator’ of Agile’s unit price?
After seeing umpteen negative price slots again today, ...
By ChandyKris , 3 days ago
-
RE: The Reality Behind a Failed Heat Pump Installation – and an IWA Insurance Rejection
@ian-w Getting back to the problem in hand, what do yo...
By JamesPa , 3 days ago
-
RE: Solar Power Output – Let’s Compare Generation Figures
@papahuhu Generally, I leave Homely to take care of mat...
By Toodles , 4 days ago
-
@judith, glad you found the story interesting. On eff...
By Mars , 4 days ago







