What is wrong here

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upup

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Was today at a petrol station. They got a deye 50kw 3 phase with 20 5kw 96aH batteries.
During the night only a few led spot lights and a cctv system works, but it does not last the whole night. They get also power from eskom, but eskom demanded a cutover switch, So when the battery die, guy must go and switch over to eskom with his hands. He got 50 solar panels. Somehow it looks to me this setup should last during the whole night.
 
tell me the solar guy had no idea how to congig the system without saying it outright

i assume it is 20 x 5kwh batteries
this 50kw inverter uses high voltage so the batteries is probably in some parrale/series config
so smells of battery imballance

he should rip out the volt meter and check the batteries voltage when it dies
or just as it finnishes charging battery full to see if all the batteries hit the same peak voltage
or check indivual batteries with coms cable to see the SOC of each battery

most likely no balancing setup in place

if one battery dies flat in the series setup it is dead in the water
 
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upup said:
Was today at a petrol station. They got a deye 50kw 3 phase with 20 5kw 96aH batteries.
During the night only a few led spot lights and a cctv system works, but it does not last the whole night. They get also power from eskom, but eskom demanded a cutover switch, So when the battery die, guy must go and switch over to eskom with his hands. He got 50 solar panels. Somehow it looks to me this setup should last during the whole night.
Click to expand...
Even with a cut over switch (Which every install should have). A correctly configured system will automatically cut over to Eskom when battery is low, and switch back to battery when it's reached a certain level.
There is no manual intervention needed. Also with regards to lasting the night, you'd have to check what yes being drawn.
 
Having a changeover is regulation, leaving it off eskom isn't ie the switch just has tk be in place to be able to move the load if needed

The inverter will switch to eskom the moment the batteries hits the software defined SOC level or it is suppose to, if battery doesn't die before that level is hit because SOC doesn't match reality

If the batteries is suppose to carry the load overnight then a bit more investigation is needed

Especially if their load is nowhere near the 100kwh battery capacity

Cause the weakest link battery/s in the out of balance bank will deteriorate quicker since it will always be cycled 100% dod

Edit : extreme care though,high voltage dc is dangerous
 
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Lupus said:
Even with a cut over switch (Which every install should have). A correctly configured system will automatically cut over to Eskom when battery is low, and switch back to battery when it's reached a certain level.
There is no manual intervention needed. Also with regards to lasting the night, you'd have to check what yes being drawn.
Click to expand...
So how does a home system, eg in Cape town , that feeds into the grid works, with a change over switch.
 
upup said:
So how does a home system, eg in Cape town , that feeds into the grid works, with a change over switch.
Click to expand...
The change over switch would be like this.
1. Inverter mode (runs the whole system through the inverter/battery/solar)
2. Off (literally off)
3. Eskom (muncipality)

Generally you keep the switch at option 1, so the entire setup runs through the inverter and it's batteries and whatever. The inverter will have cut offs for the various batteries, when it reaches those cut offs it will switch to grid mode, when the batteries are sufficiently charged it will switch back to solar/battery/grid or whatever mode is it's default.
A generator cutover switch is the same as above, but the default there is generally Eskom :-)
 
upup said:
So how does a home system, eg in Cape town , that feeds into the grid works, with a change over switch.
Click to expand...
It grid feeds via its input line

The grid feed doesn't happen via that switch , the changeover switch is post inverter

The switch has two inputs eskom and inverter output (ups/essentials) the switch just determines which line feeds the load

Even if the changeover is off the inverter can still grid feed only the load is cut off

The breaker that supplies inverter is what cuts it from grid, it is possible that some fit changeover in such a way that it is the input for inverter too

Just Depends how the electrician did it or what regulations actually is

Most installations i've seen has breaker for inverter input ie the changeover performs one function not two

Makes it easier to troubleshoot

ie you remove the load from inverter and can switch inverter on and off with its own switch

Without rebooting the whole house every time you power cycle the inverter

And only switch load back when done

While if the changeover performs both functions load diversion and inverter input

Everybody is captive while any repair/troubleshooting is being done on inverter
 
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S_L_Y_G_U_Y said:
cool story still have no freaking idea what you saying :ROFL:
Click to expand...
I also had no idea a few years ago ;) ,
Helping somebody that had problems with his system
(Higher eskom bill post solar install "new experts" what can you do)

copying settings from a buddies system and solving his battery coms problem making a custom lan cable for him got me started
Down the rabbit hole
 
upup said:
So how does a home system, eg in Cape town , that feeds into the grid works, with a change over switch.
Click to expand...
To add to what others have said, changeover switch essentially isolates the solar setup. One side of the switch the house runs as if no solar is present, other side incorporates the solar.

Feeding back in to the grid has nothing to do with the changeover.
 
Speedster said:
To add to what others have said, changeover switch essentially isolates the solar setup. One side of the switch the house runs as if no solar is present, other side incorporates the solar.

Feeding back in to the grid has nothing to do with the changeover.
Click to expand...
If the changeover doubles as input for inverter then it does come into play, but have not seen a single person with changeover setup that way
 
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