What batteries do you have, what amps can you charge them at at?
Here is a pic from the manual showing only pos fused hense my questions. Also electrically it should be ok.
The victron manual was written with european standards in mind.
Lithium SA ones two of them as per previous pictures hope to add more in future.
ignore voltage charge they put wrong ones in there
In that case you would need fuses bigger than 160a
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Yeah if I want to parallel as in option A then yes so means I will just keep them on seperate fused switches.
Why? The MP 5 charger is max 70amps, the panels are controlled by the Venus?
I am sitting in red line traffic on the western bypass trying to type. If you want, I can take a call, 0713413280
In his example, he is using 160 amp fuses, 2 x 250/100 Mppt and batteries that can accept the full current. So 100 + 100 > 160
True, but I’m under the impression, when grid tied, the Venus dictates the max charge current, not the MPPT’s.
IF the MPPT’s where not “controlled”, whole different ballgame, no?
Not true, only true for the power going through the inverter, the current to the batteries are controlled separate to the current used by the inverter.
If I switch off my Venus then 250/100 will go 100amps.
As long as the Venus is coupled with the MPPT, then the max charge amps are set at what the batteries can handle. In my case 60amps, also recommended by LBSA.
Now that brings me to the 2nd issue, regarding 100 + 100 = 200amps from the MPPT’s.
That doc Whatyamacallit posted above, says Max 100a Charge/Discharge.
Now I have bigger sells, 150ah instead of 105ah, and my doc says Max 152a Charge/Discharge.
But take note what the FULL doc says, specifically note of 2 and 3 … and that I was advised to stick to 60amps …
I’m honestly trying to get my mind around all of this …
This is what I was also wondering
Been doing other stuff today. But just wanted to say: Don’t rely on the GX device to protect your fuse from blowing. 99% of the time you will be fine, 1% of the time something could happen and the solar chargers might go into standalone mode and kill your fuse.
The fuse is there to protect the cable. Rather make it too big (relative to the expected loads/charge currents), but obviously not bigger than it has to be to protect the cable. You also don’t want nuisance blowing from the fuse.
The fuse is not there to protect the inverter or any of the equipment. If something bad happens to the equipment causing some kind of dead short, the equipment is already gone by the time the fuse blows. The fuse is there to make sure that you don’t also burn down the house.
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If you set your MPPT’s manually to a charge current that’s within battery bounds for when the CCGX is lost (for whatever reason) and then enable external control by the GX
THEN… the GX will control the current (Based on BMS <-> comms -
IF it disappears then the MPPT will use the limits you set.
Can someone QA my reasoning here…
In Revov’s reasoning for 125amp fuse on 5kva, although they have built in protections, is so that the 125amp goes first before their protections need to kick in.
Moment I do that the overall solar production drops. Lets see what Plonkster says happens on a 250/100 limited to 60amps, as a further protection measure, not that I need it, as the BMS and batts can take >100amps
Here is the correct details off website. So can handle 100A but 50A recommend!
I want to find in SANS where it says negative needs to be fused, if not will go with option D
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All this fora fuse that cost less than R90. Such a small price to pay for the extra peace of mind.
To be honest, I dont know a single electrician or engineer that will sign the installation off without a double fuse disconnector. May also be the reason that none of the online shops offer a single pole fuse holder as battery protection. All of my suppliers only offer 2 and 3 pole… Wonder why…
I don’t see how this is the same as the example I answered on above.
Just fuse the Pos … NOTHING wrong with that AND is the accepted norm. 