Abe53

We have several off-grid installations requiring geyser control, some with old hardware, and have unreliable wi-fi coverage which rules out Internet of Things. Scorp007 's proposal of using a XH M602 charger should work, I use buck converters with similar up-down buttons to charge DIY li-ion batteries to fine tolerances. Will tinker and revert. Thanks again for your attention in this matter... ;-)

The solution is very simple. Just use a charger controller and inverter the output via n/c contact to switch of the geyser when voltage drops to the set level. Then the on board relay will switch off at charged voltage which will then provide power to the geyser again.
Use an external relay if you don't trust the on board blue relay. Setting points for on/off as low as 0.1V apart and up to 60V. This model has an output of 230V and the input that is switched is 230V as well. Thus external relay will also be cheaper 230V than DC Relays.
XH M602 Cost R145 or lower.
PM me for details if in doubt. Long time no speak.

Solar is the perfect DIY project to wean yourself off the grid particularly and guavement in general. "Ons doen dit self!"
A great advantage is that the user will do the best job he/she can, (no wokes here), learns the system from inside out, and reaps the benefit of reliability. Also can troubleshoot problems and fix it. Few if any call-outs. YouTube is the great leveller, has saved me plenty. No, I do not believe everything there, but have common sense.
Stories about bad and indeed dangerous installations by supposedly "professional installers" abound. Instead of attempting to upgrade all installers and force their use, I think it would be better to educate users on how to do a good install themselves. It is not rocket science. Yes, get a safety inspector if you do not trust yourself.
It is the prize sponsors prerogative to make the rules for the competition and rub up to the trade, but it will not endear them to the end customer.

Hi Carl, Yes, would like that Leaf for the 20km school run. Will send detail by PM.
Have excess production on my solar PV to charge with.
Am in Gauteng but flying down to Cape for the holidays. However, will have to send the leaf by trailer...
 

Hi Carl, Yes, would like that Leaf for the 20km school run. Will send detail by PM.
Have excess production on my solar PV to charge with.
Am in Gauteng but flying down to Cape for the holidays. However, will have to send the leaf by trailer...
 

Watching from the sideline, amused...
Pylontech seems known to run their batteries hard. 15 cells vs 16 and such. One of my systems have 2 x US3000 on a Victron inverter and I occasionally see slight over voltage warnings, duly ignored. My standard installation 14s 100p 18650 Li-Ion cell batteries (don't laugh, they work very well) run a very conservative 44-55V profile regulated by the inverters, sans BMS. When I occasionally don my BMS hat, I sometimes replace a few cells, but then, they are virtually free... Ran a 53s 34p backup bank the other day and thought to check health: 34 changeover switches to the 100W test load makes that easy, and not a single cell needed changing. NMC chemistry still rocks! My 12yr old Samsung laptop still has 3 hour battery life. (Used Samsung battery management, 80% max.)

Watching from the sideline, amused...
Pylontech seems known to run their batteries hard. 15 cells vs 16 and such. One of my systems have 2 x US3000 on a Victron inverter and I occasionally see slight over voltage warnings, duly ignored. My standard installation 14s 100p 18650 Li-Ion cell batteries (don't laugh, they work very well) run a very conservative 44-55V profile regulated by the inverters, sans BMS. When I occasionally don my BMS hat, I sometimes replace a few cells, but then, they are virtually free... Ran a 53s 34p backup bank the other day and thought to check health: 34 changeover switches to the 100W test load makes that easy, and not a single cell needed changing. NMC chemistry still rocks! My 12yr old Samsung laptop still has 3 hour battery life. (Used Samsung battery management, 80% max.)

Done. Would also like to see statistics when available?

Done. Would also like to see statistics when available?

Good evening from our home powered by 18650's in Ph6 loadshedding.
P1000, do you perhaps drive a car with a tank full of incendiary fluid? At speed in close encounters with taxis driven by reckless maniacs? (They say heaven welcomes taxi drivers, they convert more heathens than the priests... 😉
Yes, 18650's have a small risk of overheating and burning (not exploding) if mismanaged. However, I minimize the risk by:
1. Testing all cells, checking temperatures by hand and with a laser meter while charging at 1A, weeding out the heaters. (The red Sanyo's are the usual suspects)
2. Using them very conservatively, low cutout at 3.1V, charge to max 3.9V (4.25V allowed) Draw max 1A (<0.5C) Charge max 0.5A
3. Fitting every string with a 4A fuse. (Yes, once popped 36 fuses when switching on big loads with only three trays of 14s 10p batteries on the wall.)
4. DC rated CB and fuse on + and  -
5. The 18650's are not soldered, just butted + to - (after mangling the + to protrude) contained only by a 25x16mm PVC trunking, if disturbed, the battery just falls apart cutting the circuit.
I have survived 69 years with some close encounters, not at all worried about the thousands of 18650's on the wall in the passage.

Hi Pierre D, Why worry? They call the DC powered home "Edison's revenge."
Eventually lights (LED's are native 3VDC) and most electronics just reduce 220VAC to 12VDC anyway.

Good evening from our home powered by 18650's in Ph6 loadshedding.
P1000, do you perhaps drive a car with a tank full of incendiary fluid? At speed in close encounters with taxis driven by reckless maniacs? (They say heaven welcomes taxi drivers, they convert more heathens than the priests... 😉
Yes, 18650's have a small risk of overheating and burning (not exploding) if mismanaged. However, I minimize the risk by:
1. Testing all cells, checking temperatures by hand and with a laser meter while charging at 1A, weeding out the heaters. (The red Sanyo's are the usual suspects)
2. Using them very conservatively, low cutout at 3.1V, charge to max 3.9V (4.25V allowed) Draw max 1A (<0.5C) Charge max 0.5A
3. Fitting every string with a 4A fuse. (Yes, once popped 36 fuses when switching on big loads with only three trays of 14s 10p batteries on the wall.)
4. DC rated CB and fuse on + and  -
5. The 18650's are not soldered, just butted + to - (after mangling the + to protrude) contained only by a 25x16mm PVC trunking, if disturbed, the battery just falls apart cutting the circuit.
I have survived 69 years with some close encounters, not at all worried about the thousands of 18650's on the wall in the passage.

Good evening from our home powered by 18650's in Ph6 loadshedding.
P1000, do you perhaps drive a car with a tank full of incendiary fluid? At speed in close encounters with taxis driven by reckless maniacs? (They say heaven welcomes taxi drivers, they convert more heathens than the priests... 😉
Yes, 18650's have a small risk of overheating and burning (not exploding) if mismanaged. However, I minimize the risk by:
1. Testing all cells, checking temperatures by hand and with a laser meter while charging at 1A, weeding out the heaters. (The red Sanyo's are the usual suspects)
2. Using them very conservatively, low cutout at 3.1V, charge to max 3.9V (4.25V allowed) Draw max 1A (<0.5C) Charge max 0.5A
3. Fitting every string with a 4A fuse. (Yes, once popped 36 fuses when switching on big loads with only three trays of 14s 10p batteries on the wall.)
4. DC rated CB and fuse on + and  -
5. The 18650's are not soldered, just butted + to - (after mangling the + to protrude) contained only by a 25x16mm PVC trunking, if disturbed, the battery just falls apart cutting the circuit.
I have survived 69 years with some close encounters, not at all worried about the thousands of 18650's on the wall in the passage.

Good evening from our home powered by 18650's in Ph6 loadshedding.
P1000, do you perhaps drive a car with a tank full of incendiary fluid? At speed in close encounters with taxis driven by reckless maniacs? (They say heaven welcomes taxi drivers, they convert more heathens than the priests... 😉
Yes, 18650's have a small risk of overheating and burning (not exploding) if mismanaged. However, I minimize the risk by:
1. Testing all cells, checking temperatures by hand and with a laser meter while charging at 1A, weeding out the heaters. (The red Sanyo's are the usual suspects)
2. Using them very conservatively, low cutout at 3.1V, charge to max 3.9V (4.25V allowed) Draw max 1A (<0.5C) Charge max 0.5A
3. Fitting every string with a 4A fuse. (Yes, once popped 36 fuses when switching on big loads with only three trays of 14s 10p batteries on the wall.)
4. DC rated CB and fuse on + and  -
5. The 18650's are not soldered, just butted + to - (after mangling the + to protrude) contained only by a 25x16mm PVC trunking, if disturbed, the battery just falls apart cutting the circuit.
I have survived 69 years with some close encounters, not at all worried about the thousands of 18650's on the wall in the passage.

Good evening from our home powered by 18650's in Ph6 loadshedding.
P1000, do you perhaps drive a car with a tank full of incendiary fluid? At speed in close encounters with taxis driven by reckless maniacs? (They say heaven welcomes taxi drivers, they convert more heathens than the priests... 😉
Yes, 18650's have a small risk of overheating and burning (not exploding) if mismanaged. However, I minimize the risk by:
1. Testing all cells, checking temperatures by hand and with a laser meter while charging at 1A, weeding out the heaters. (The red Sanyo's are the usual suspects)
2. Using them very conservatively, low cutout at 3.1V, charge to max 3.9V (4.25V allowed) Draw max 1A (<0.5C) Charge max 0.5A
3. Fitting every string with a 4A fuse. (Yes, once popped 36 fuses when switching on big loads with only three trays of 14s 10p batteries on the wall.)
4. DC rated CB and fuse on + and  -
5. The 18650's are not soldered, just butted + to - (after mangling the + to protrude) contained only by a 25x16mm PVC trunking, if disturbed, the battery just falls apart cutting the circuit.
I have survived 69 years with some close encounters, not at all worried about the thousands of 18650's on the wall in the passage.

Just an update on the health of my first 18650 powerwall:
Have not checked the 53s 34p for the last year but coming home at sunset in load shedding (blackout) I switched to the Eaton PX9 because son wanted a pizza and I wanted to spare the Solis's 14s 100p for in case EKSDOM did not come back . With oven, microwave, kettle and more, the wall only dropped from 206V to 199V after dinner. So I switched off all strings and checked them today. All 1802 x 18650 cells at healthy Volts and pulling their weight, nice to see! No BMS, no pumping up or drawing down, every cell finds its happy place.

A stolen battery? 😉 Hat, coat, door...

Hello Don, which Growatt inverter have you? I bought a used 5000 ES and installed with a homebuilt 18650 powerwall with no BMS and it works fine. Perhaps change settings to user-defined battery? Check those volt readings with a handheld multimeter while inverter is acting up?

A stolen battery? 😉 Hat, coat, door...

Hi Heine,
I second Scorp007's proposal to just put an array panels on the Western side to a total of similar Volts of the Eastern array and parallel to your single MPPT.
Just confirm midday Amps will not exceed max allowed. Cost of separate charger and/or switchgear is better invested in more panels.

Good evening Powerites,
Thanks Jason for the timely powerwall topic.
It was funny to see a load shedding thread on another forum descend to a bragging contest of "my solar system is bigger than yours... 😉
I cannot compete with Leszek or Delphinus's workmanship but while I can get 18650 Lithium-Ion cells for (almost) free I will keep on using them for our houses on the farm. KISS is my motto. Herewith photos of one of my 14S powerwalls, this one currently 100P . Don't laugh, it works fine, although I have to occasionally don my BMS hat and use that thing with the 2x24V bulbs to check strings under load to diagnose and replace faulty cells.
My reason for showing this is to inquire if a forumite perhaps has an idea for a better architecture for a 18650 cell powerwall?
Ja, ons kan self!
(Yes, we can DIY)

Good evening Powerites,
Thanks Jason for the timely powerwall topic.
It was funny to see a load shedding thread on another forum descend to a bragging contest of "my solar system is bigger than yours... 😉
I cannot compete with Leszek or Delphinus's workmanship but while I can get 18650 Lithium-Ion cells for (almost) free I will keep on using them for our houses on the farm. KISS is my motto. Herewith photos of one of my 14S powerwalls, this one currently 100P . Don't laugh, it works fine, although I have to occasionally don my BMS hat and use that thing with the 2x24V bulbs to check strings under load to diagnose and replace faulty cells.
My reason for showing this is to inquire if a forumite perhaps has an idea for a better architecture for a 18650 cell powerwall?
Ja, ons kan self!
(Yes, we can DIY)

Good evening Powerites,
Thanks Jason for the timely powerwall topic.
It was funny to see a load shedding thread on another forum descend to a bragging contest of "my solar system is bigger than yours... 😉
I cannot compete with Leszek or Delphinus's workmanship but while I can get 18650 Lithium-Ion cells for (almost) free I will keep on using them for our houses on the farm. KISS is my motto. Herewith photos of one of my 14S powerwalls, this one currently 100P . Don't laugh, it works fine, although I have to occasionally don my BMS hat and use that thing with the 2x24V bulbs to check strings under load to diagnose and replace faulty cells.
My reason for showing this is to inquire if a forumite perhaps has an idea for a better architecture for a 18650 cell powerwall?
Ja, ons kan self!
(Yes, we can DIY)

Good evening Powerites,
Thanks Jason for the timely powerwall topic.
It was funny to see a load shedding thread on another forum descend to a bragging contest of "my solar system is bigger than yours... 😉
I cannot compete with Leszek or Delphinus's workmanship but while I can get 18650 Lithium-Ion cells for (almost) free I will keep on using them for our houses on the farm. KISS is my motto. Herewith photos of one of my 14S powerwalls, this one currently 100P . Don't laugh, it works fine, although I have to occasionally don my BMS hat and use that thing with the 2x24V bulbs to check strings under load to diagnose and replace faulty cells.
My reason for showing this is to inquire if a forumite perhaps has an idea for a better architecture for a 18650 cell powerwall?
Ja, ons kan self!
(Yes, we can DIY)

Good evening Powerites,
Thanks Jason for the timely powerwall topic.
It was funny to see a load shedding thread on another forum descend to a bragging contest of "my solar system is bigger than yours... 😉
I cannot compete with Leszek or Delphinus's workmanship but while I can get 18650 Lithium-Ion cells for (almost) free I will keep on using them for our houses on the farm. KISS is my motto. Herewith photos of one of my 14S powerwalls, this one currently 100P . Don't laugh, it works fine, although I have to occasionally don my BMS hat and use that thing with the 2x24V bulbs to check strings under load to diagnose and replace faulty cells.
My reason for showing this is to inquire if a forumite perhaps has an idea for a better architecture for a 18650 cell powerwall?
Ja, ons kan self!
(Yes, we can DIY)