I have been trolling the website or forum as a guest for a number of months, and recently joined, you guys have an amazing forum going with a wealth of knowledge. I hope that eventually one day i can help to add or plow back some knowledge. For the current time being i am unfortunately still a noob. Hope i followed all the guidelines i tried, so be gentle, it is my first post here...
Sorry for the long read, just some background to try and give you guys better understanding of the details surrounding my setups. So i started playing around with the solar field about a year or so ago, unfortunately i only discovered the forum after struggling through some teething problems myself. Long and short, i am a mechanical engineer by trade, so by no means really qualified from an electrical perspective bar the limited knowledge imparted from some limited electrical subjects forced unto me while at varsity (back then all i learned was that all electronic equipment works with black smoke, once smoke is outside it no longer works and is challenging to get the smoke back inside.... just kidding :-))
Anyway, i wanted to install three sites, my own home, my dad's home and my dads office. For my own home and father's home we wanted so safe money spent on eskom power spent (bills was ranging from 2-4k), as well as try and go off grid. For my dad's office the main idea is to be able to just go through load shedding sessions since his utility bill is very low already since it is a smallish business mainly relying on computers and few aircons being the main culpruts, so once load shedding hits we only need to power a few lights and maybe 5 or six computers.
The hardware was all bought at inverter warehouse over at gary, and the batteries at the sun pays. setups was as follow:
Father's house:
- canadian solar 330watt panels x 14 (two strings, 7 panels in series for each string connected to the two seperate mppt's of the goodwe)
- goodwe 5kw EM inverter
- 2 x 4.8kw sun pays lithium batteries
My own home:
- 20 x canadian solar 330watt panels (two strings, 10 panels connected in series to the two separate mppt's of the goodwe)
- goodwe 5kw ES inverter
- 5 x 4.8kw sun pays lithium batteries
My dad's office setup:
- 4 x 330 watt canadian solar panels (one string, 2 panels in series, then connected in parallel with another string of two in series, connected to the mecer mppt)
- mecer 5kw inverter
- 1 x 4.8kw the sunpays lithium battery
So all three systems i installed myself, i learned as we went along, i am however very precise or pedantic when it comes to quality of installation etc etc, so i first tried the first install with a local installer or electrician and very quickly saw that it will not end well, since i did not like the quality and workmanship etc. I decided to do it myself as and when i have time, over weekend etc so took quite some time to finish all three installations. The system at my dad's house as well as my home, have been completed, both with change over switches and proper breaker and isolaters between the DB, DC side form panel and batteries at all three the site i installed it similar. I think all should be in order, both systems are working and seem to be performing well. I have two problems i hope you guys can help with...
My own system seems to not like it when the actual combined loads in the house goes over 4.5kw, then it throttles back to 4.2kw (Whether the available solar is 5kw at that stage or not....), it can easily be seen in sems, the graph will make a tabletop flat graph (this is not due to weather, the graph was increasing steadily and will flat off obviously being throttled since it can be seen that this being done by the inverter controller), which rises when the load goes less or the pv drops then it will start to follow the sinus curve or graph again as expected. It will go over 4.5kw though if the house loads is say 4kw, and it can charge the battery at 1-2kw depending on what the solar can provide... however, as soon as the house load alone increase over about 4.5kw it will throttle back to around 4.2kwin total and basically "drop" the available pv, it won't even then charge the rest to the batteries, until the house loads drops then it will charge at for example 2.5kw on the batteries and house load will be at 2.5kw giving me around 5kw total load, it can however never reach 5kw on only the house loads alone, even if the pv is suffient, it can generate around 5-5.5kw granted the house load is below the 4.5kw, and then the balance will go to the batteries if the house load increase over 4.2kw then the pv will decrease to 4.2kw throttled and the rest will be fed from the grid... why is this... i thought it can do 6kw if not on the backup side....?
Second issue, i only got round to finishing the mecer install at my dads office over the weekend, the manual is k@k, to say the least, there is no wiring diagram whatsoever so i had to try and figure it out myself, so not sure if the problem is maybe there. Currently though the system is not happy and not doing what i want it to do or thought it can and should do. Wiring was done as follow (keep in mind there will never be a stove on, they have gas installed, stove has been disconnected, and the geyser is only switched on on saturdays for maid to have warm water....) The inverter will never run of batteries with the geyser or any single load larger than 1kw turned on it will only be 5 or 6 office computers and their lcd screens, so i guess no more than 3kw at most ever combined load....
So i wired the solar and batteries where they should be, the mecer only has one AC output, unlike the goodwe that has two ac outputs, one for main, and one for backup, and one ac input. So i wired the incomer 220v straight into the changeover switch, then into the inverter at the ac input (they have a 12kw generator i wired on the alternate supply for the changeover so also running directly into the inverter if switch is changed over). Then i wired the ac output from the inverter to the DB into the mains and earth leakage, since i did not want to split the db since there is no stove connected, and the geyser is off, 6 out of 7 days, and always when grid is not present, so when the grid is present, and the geyser is on, should the inverter not just supplement the extra power needed for the geyser from the grid or generator...? Should i wire the geyser directly from the incomer rather....?
So the unit powers on, but when i switch on the circuits it starts for a few minutes and then shuts down or reboots.... they had loadshedding on saturday, so the grid was down, but even if the generator is running, it did not seem like it was poewering anything from the generator, so it was complaining about the battery voltage being too low, but SHOULDit not be able to power loads from the grid/generator when the battery or pv is not sufficient, i want to configure it anyway never to use batteries unless there is loadshedding to ensure the battery is always fully charged to ensure that they can work max time before the battery is flat. Is my wiring incorrect, why did it not pull from the grid/generator....? What should my battery setting be... the basic settings for the battery is as follow as per its manual.... the menu in the inverter seems dodge and i am not entirely sure what is should put where... if you guys can give some guidance it will really be appreciated! thanx in advance, and stay classy, this forum rocks!!
Battery recommended settings:
48v 100ah/h
charge limit coefficient 0.05c-0.5c10
float voltage 51v
boost charge voltage 53.5v
equalized charge voltage 53.5v
float charge voltage 51v
low voltage alarm 47v
load low voltage disconnection voltage 46v
battery low voltage disconnection threshold 44v
sorry for the long read guys,i appreciate all and any input!
Question
Saint
Hi everyone,
I have been trolling the website or forum as a guest for a number of months, and recently joined, you guys have an amazing forum going with a wealth of knowledge. I hope that eventually one day i can help to add or plow back some knowledge. For the current time being i am unfortunately still a noob. Hope i followed all the guidelines i tried, so be gentle, it is my first post here...
Sorry for the long read, just some background to try and give you guys better understanding of the details surrounding my setups. So i started playing around with the solar field about a year or so ago, unfortunately i only discovered the forum after struggling through some teething problems myself. Long and short, i am a mechanical engineer by trade, so by no means really qualified from an electrical perspective bar the limited knowledge imparted from some limited electrical subjects forced unto me while at varsity (back then all i learned was that all electronic equipment works with black smoke, once smoke is outside it no longer works and is challenging to get the smoke back inside.... just kidding :-))
Anyway, i wanted to install three sites, my own home, my dad's home and my dads office. For my own home and father's home we wanted so safe money spent on eskom power spent (bills was ranging from 2-4k), as well as try and go off grid. For my dad's office the main idea is to be able to just go through load shedding sessions since his utility bill is very low already since it is a smallish business mainly relying on computers and few aircons being the main culpruts, so once load shedding hits we only need to power a few lights and maybe 5 or six computers.
The hardware was all bought at inverter warehouse over at gary, and the batteries at the sun pays. setups was as follow:
Father's house:
- canadian solar 330watt panels x 14 (two strings, 7 panels in series for each string connected to the two seperate mppt's of the goodwe)
- goodwe 5kw EM inverter
- 2 x 4.8kw sun pays lithium batteries
My own home:
- 20 x canadian solar 330watt panels (two strings, 10 panels connected in series to the two separate mppt's of the goodwe)
- goodwe 5kw ES inverter
- 5 x 4.8kw sun pays lithium batteries
My dad's office setup:
- 4 x 330 watt canadian solar panels (one string, 2 panels in series, then connected in parallel with another string of two in series, connected to the mecer mppt)
- mecer 5kw inverter
- 1 x 4.8kw the sunpays lithium battery
So all three systems i installed myself, i learned as we went along, i am however very precise or pedantic when it comes to quality of installation etc etc, so i first tried the first install with a local installer or electrician and very quickly saw that it will not end well, since i did not like the quality and workmanship etc. I decided to do it myself as and when i have time, over weekend etc so took quite some time to finish all three installations. The system at my dad's house as well as my home, have been completed, both with change over switches and proper breaker and isolaters between the DB, DC side form panel and batteries at all three the site i installed it similar. I think all should be in order, both systems are working and seem to be performing well. I have two problems i hope you guys can help with...
My own system seems to not like it when the actual combined loads in the house goes over 4.5kw, then it throttles back to 4.2kw (Whether the available solar is 5kw at that stage or not....), it can easily be seen in sems, the graph will make a tabletop flat graph (this is not due to weather, the graph was increasing steadily and will flat off obviously being throttled since it can be seen that this being done by the inverter controller), which rises when the load goes less or the pv drops then it will start to follow the sinus curve or graph again as expected. It will go over 4.5kw though if the house loads is say 4kw, and it can charge the battery at 1-2kw depending on what the solar can provide... however, as soon as the house load alone increase over about 4.5kw it will throttle back to around 4.2kwin total and basically "drop" the available pv, it won't even then charge the rest to the batteries, until the house loads drops then it will charge at for example 2.5kw on the batteries and house load will be at 2.5kw giving me around 5kw total load, it can however never reach 5kw on only the house loads alone, even if the pv is suffient, it can generate around 5-5.5kw granted the house load is below the 4.5kw, and then the balance will go to the batteries if the house load increase over 4.2kw then the pv will decrease to 4.2kw throttled and the rest will be fed from the grid... why is this... i thought it can do 6kw if not on the backup side....?
Second issue, i only got round to finishing the mecer install at my dads office over the weekend, the manual is k@k, to say the least, there is no wiring diagram whatsoever so i had to try and figure it out myself, so not sure if the problem is maybe there. Currently though the system is not happy and not doing what i want it to do or thought it can and should do. Wiring was done as follow (keep in mind there will never be a stove on, they have gas installed, stove has been disconnected, and the geyser is only switched on on saturdays for maid to have warm water....) The inverter will never run of batteries with the geyser or any single load larger than 1kw turned on it will only be 5 or 6 office computers and their lcd screens, so i guess no more than 3kw at most ever combined load....
So i wired the solar and batteries where they should be, the mecer only has one AC output, unlike the goodwe that has two ac outputs, one for main, and one for backup, and one ac input. So i wired the incomer 220v straight into the changeover switch, then into the inverter at the ac input (they have a 12kw generator i wired on the alternate supply for the changeover so also running directly into the inverter if switch is changed over). Then i wired the ac output from the inverter to the DB into the mains and earth leakage, since i did not want to split the db since there is no stove connected, and the geyser is off, 6 out of 7 days, and always when grid is not present, so when the grid is present, and the geyser is on, should the inverter not just supplement the extra power needed for the geyser from the grid or generator...? Should i wire the geyser directly from the incomer rather....?
So the unit powers on, but when i switch on the circuits it starts for a few minutes and then shuts down or reboots.... they had loadshedding on saturday, so the grid was down, but even if the generator is running, it did not seem like it was poewering anything from the generator, so it was complaining about the battery voltage being too low, but SHOULDit not be able to power loads from the grid/generator when the battery or pv is not sufficient, i want to configure it anyway never to use batteries unless there is loadshedding to ensure the battery is always fully charged to ensure that they can work max time before the battery is flat. Is my wiring incorrect, why did it not pull from the grid/generator....? What should my battery setting be... the basic settings for the battery is as follow as per its manual.... the menu in the inverter seems dodge and i am not entirely sure what is should put where... if you guys can give some guidance it will really be appreciated! thanx in advance, and stay classy, this forum rocks!!
Battery recommended settings:
48v 100ah/h
charge limit coefficient 0.05c-0.5c10
float voltage 51v
boost charge voltage 53.5v
equalized charge voltage 53.5v
float charge voltage 51v
low voltage alarm 47v
load low voltage disconnection voltage 46v
battery low voltage disconnection threshold 44v
sorry for the long read guys,i appreciate all and any input!
thanx
peace out!
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