Panel recommendations
- Thread starter Salisburytree
- Start date
Yes I think so , epever are a medium quality brand . The good end of the cheapo imports ...
there are better, higher quality, more reliable MPPTs out there ,. but obviously for a LOT more money.
That one you just posted looks suitable for 2x panels in series voltage wise (37voc x 2 = 74voc) , but the panels can output more than their Voc when it's cold out
Use this calculator with all the panel specs:
Solar panel maximum voltage calculator - How to work out the max voltage
To get the maximum solar panel voltage you should expect from your solar panel, use our solar panel maximum voltage calculator.
gold-coast-solar-power-solutions.com.au
It comes to roughly 84v for 2 panels in series, and then you'd need 20% clear blue water above that as a safety buffer , 110v~ . Well under that epever's 138v max
And it says 800w max input , again no issues there
Salisburytree
New Member
Thank you!Yes I think so , epever are a medium quality brand . The good end of the cheapo imports ...
there are better, higher quality, more reliable MPPTs out there ,. but obviously for a LOT more money.
That one you just posted looks suitable for 2x panels in series voltage wise (37voc x 2 = 74voc) , but the panels can output more than their Voc when it's cold out
Use this calculator with all the panel specs:
Solar panel maximum voltage calculator - How to work out the max voltage
To get the maximum solar panel voltage you should expect from your solar panel, use our solar panel maximum voltage calculator.
It comes to roughly 84v for 2 panels in series, and then you'd need 20% clear blue water above that as a safety buffer , 110v~ . Well under that epever's 138v max
And it says 800w max input , again no issues there
I did a simple calculator and I got the same reading but there were alot of inputs into the calculator that I wasn't sure I was getting right but it seems maybe I was doing the right thing. Thank you again for your help!
Panels have been ordered, just trying to strike a deal on the mppt, little concerned that this model does not support lithium should I want to upgrade the battery bank in the future.
When I think about 60amps coming out of the controller it makes me think more on the safety aspect of things, it dosent take many amps to kill someone! I also think about accidentally touching the battery charging cable whilst its pumping out 60amp I going to blow me to France.
My pleasure
Haha yea try not to do that then ? So long as you mind your P & Qs and do things the right way you'll be ok .. it's fine to touch one cable , even one terminal while it's running... It's touching both that'll get you a shock lol
MisterSandals
Participation Medalist
A "user defined" battery setting is often better than a lithium setting. The ability to turn off equalization (or set eq time to zero) is crucial.
.
Also don't forget it's 12vdc , not particularly dangerous ... A man once told me the only way you could kill someone with a 12v battery is hit them over the head with it ! ?
Now your solar side is a different story, 2 panels in series 70v+ that'll give you a jolt
Now your solar side is a different story, 2 panels in series 70v+ that'll give you a jolt
Salisburytree
New Member
I was thinking more of the cables that come out of the mppt at 60 amps would give me a tickle ? iv had a few 12v shocks, no concerns there ?
Salisburytree
New Member
Ok so this controller would leave me okay with a battery upgrade, thats great to know. Thank you
Salisburytree
New Member
Having a good read of the somewhat vague manuals and data sheets for the solar panels, I need to look at grounding and a circuit breaker before the mppt and possibly after should the charge controller fail?
I know from the charge controller I will have 60 amps to break.
From the panels to controller because I'm wiring in series it will be the individual value of amps from one panel, if iv been listening right? ? I need to double check what that actually was!
I know from the charge controller I will have 60 amps to break.
From the panels to controller because I'm wiring in series it will be the individual value of amps from one panel, if iv been listening right? ? I need to double check what that actually was!
Fuse or a circuit breaker either will do.
Fuses work out cheaper because you need a special 'dc rated' circuit breaker and they cost a bit
look at this 100a mega fuse for between MTTP > batteries
and also this DC 20amp breaker for solar panel > mppt
It's good to have an breaker between the panels and the mppt . Your mppt is ok to have JUST battery power , but it does not like to have JUST solar no battery (it can blow the mppt).
The actual machine in the mppt runs off the batteries, not the solar, if that makes sense ?
What size cable are you going to use for mppt > battery?
Salisburytree
New Member
Id I remember right the epever manual recommends 16mm cable, I think you also send me a link along those lines too
Salisburytree
New Member
Brilliant, if a fuse will do the job I shal order one of them. Presumably just the one on the live.
Toolstation have some clearance breakers, so I will grab one of them. Will see if they have a 100 amp going cheap as I guess it could be handy to shut the panels off from the controller
yes sorry lol 16mm is good.
Fuses should be 20% above the max amps power , at least 75amp for your mppt .
But 100amp is fine so long as the cable is still protected ( 16mm cable max rating is 100 amp so all good)
Fuses should be 20% above the max amps power , at least 75amp for your mppt .
But 100amp is fine so long as the cable is still protected ( 16mm cable max rating is 100 amp so all good)
Salisburytree
New Member
Perfect , looks like we are in business!
Just need to work out the grounding cable size from the panels, any ideas on this front?
Groundings not something I've looked into much , I know people here have different ideas , some do some don't
I'm not sure about it
Salisburytree
New Member
Yes I see the mixed opinions when it comes to grounding, might just do it for the safety aspect.
Would you recommend me sending the load cable from the mppt through a breaker before it hits the load?
I'm just thinking along the lines of the controller breaking...
zanydroid
Solar Wizard
Um. All metal parts should be grounded. And ground fault protection installed and understood. It is not as simple as how RCD works. Or if omitted the risk understood and accepted. Skipping this is IMO inappropriate approach to due diligence.
There will of course be code differences between countries.
AFAIK the controversy is around where the ground rods should be and whether the ground should connect back to your house. That part I’m not sure about. If you don’t connect back to anything other than the shed and array, and they are next to each other, the controversy sort of goes away.
There will of course be code differences between countries.
AFAIK the controversy is around where the ground rods should be and whether the ground should connect back to your house. That part I’m not sure about. If you don’t connect back to anything other than the shed and array, and they are next to each other, the controversy sort of goes away.
I think I'm right in saying there's no codes covering off grid installation in the UK
zanydroid
Solar Wizard
That is weird. Anything connected to a structure is supposed to be covered in the US. Whether it is enforced is another question. I guess there's questionable what counts as a structure.
Either way you should understand the code pertaining to this safety issue in the most similar situations where code exists, and implement the appropriate level.
definitely comes under building regs (code ) if you mount to a house / commercial unit. Off grid solar is a bit of a wild west here, it's not very popular or well regulated
Yes yes absolutely ?,
Salisburytree
New Member
I think I'm definitely going to ground via means of an earth rod to be on the safe side
Salisburytree
New Member
Am I okay with a 63amp breaker between the mppt and batteries?
I keep reading bad reviews about these ebay cheap breakers which has put me off. Renogy have dc breakers but their biggest is 63amp and I know you mentioned a 100amp fuse between the two.
zanydroid
Solar Wizard
The problem with breakers is that DC interruption is inherently harder and you need to really understand the implications of different approaches, and TRUST it's not a counterfeit etc.
Fuses work with much simpler electrical engineering theory, and there's less variation (I think speed, steady state current, interrupt rating). I wouldn't be worried about them being a consumable. If you blow a pricy 100a fuse, that fuse saved you from some extreme pain, a bargain.
Fuses work with much simpler electrical engineering theory, and there's less variation (I think speed, steady state current, interrupt rating). I wouldn't be worried about them being a consumable. If you blow a pricy 100a fuse, that fuse saved you from some extreme pain, a bargain.
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