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Maximum watt Input on controller

Solar nube

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Hi guys new to this. My tracer 4215BN solar epic 40amp controller says 520w 150 voc 40 amp. Now my question is with a 520w panel it puts out 50v. So can I have three of these up to 150v. Or enough panels upto 150 Voc or 40amps as long as I don't go over. I'm confused as it also says 520w. But if you only had 520w you cound never get the max in the controller. I hope this makes sense.
 
So can I have three of these up to 150v.
No, only 2 in series. 3 would be over 150V when it got colder than 25C (77F).
40A is the charging amps not input limit.

You can have more than 520W array. It’s common to over panel in terms of watts.
520W / 14V charging = 37A
 
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Hi guys new to this. My tracer 4215BN solar epic 40amp controller says 520w 150 voc 40 amp.
Nice little controller.
Now my question is with a 520w panel it puts out 50v. So can I have three of these up to 150v. Or enough panels up to 150 Voc or 40amps as long as I don't go over.
Yes and no, you have to factor in both ends of the controller. Can it take up to 150v? Yes. Could you put 40a into the SCC? Yes. Could you do it both at the same time? No. That's where the wattage limits come in since MPPT is trying to get the maximum WATTAGE out of the panels. If you put in 40a @ 150v that would be 6000w of power. The controller is trying to maximize the OUTPUT at 13v @ 40a which would be where that 520w limit comes from. If you pumped 6000w into a controller on a 12v battery, that would be 6000w/13v = 462A!! :oops:
I'm confused as it also says 520w.
Yup, factoring in a 12v nominal system it's using 13v for safety and the traces and electronics inside can handle up to 40a before they get so hot they melt and catch fire. 40a * 13v = 520w.

But if you only had 520w you couldn't never get the max in the controller. I hope this makes sense.
Yup, totally makes sense if you're not familiar with how the controller is trying to work. On paper it should handle 6000w on the input, it's the output that's gonna light off if you do that thought. :)

Make more sense now?
 
Cheers guys but still a bit confused I guess I'm looking at an exact answer. How many watts in my panel solar array in parallel should I put in to this controller to make it work the best with my 12v set up. IE how many panels at how many watts.
 
Cheers guys but still a bit confused I guess I'm looking at an exact answer.
Without things like daily weather tracking, directional considerations, all the minutia it's really hard to do an exact answer. The best thing we can do is give you a safe estimate and get you going in the right direction.
How many watts in my panel solar array in parallel should I put in to this controller to make it work the best with my 12v set up. IE how many panels at how many watts.
With your 520w panel specced above the safe answer would be 1 panel as that's all the output amperage your SCC can take.
If you had really krappy weather every day then you could maybe use 2 if you pointed them in different directions (SE for morning sun and SW for afternoon sun) because you'd never have more than 1 panel putting out full power at a time. You'd have 1 working well until late morning, then 2 working OK, then 1 working well all afternoon. Hopefully (and there IS a risk on this) the total wattage should be low enough that the SCC can dissipate the excess power as heat and not cook itself off. Rule of thumb is no more than 50% over paneling depending on environmental factors.

We've had a few threads on here of people asking how to disconnect panels for the summer months to avoid over-watting their controllers and turning the panels back on in the fall. It's a thing. o_O

That's about the max paneling your SCC can handle. If you're using different panels then you'll have to have the VoC and Imp of the other panels to math out what you could use.
 
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Thankyou I will be getting more batteries a total of 600ah lithium . I live in Tenerife so hot most of the year . So I guess to charge the battery bank I will have to go with one controller per 520w panel.im guess I'm buying more controllers and panels.one controller one panel .just one controller and one panel will take too long to charge 600ah right?
 
The best way to go would be larger controllers. If you're stuck with a 12v system then your 40a gets you 520w but a 100a gets you 1200w. The other option would be going with a higher voltage system since SCC's are rated for Amps @ nominal voltage, so your 40a controller can take 1040w of panel on a 24v system.

Fortunately you can parallel SCC's until you run out of space for the parts. :) With 600Ah of 12v battery (7200Wh) and an average of 5 hours a day of sunlight you're going to need about 1500w of panels to charge that up in 1 day, or 140a of SCC capacity @ 12v nominal, 75a at 24v nominal.
 
The best way to go would be larger controllers. If you're stuck with a 12v system then your 40a gets you 520w but a 100a gets you 1200w. The other option would be going with a higher voltage system since SCC's are rated for Amps @ nominal voltage, so your 40a controller can take 1040w of panel on a 24v system.

Fortunately you can parallel SCC's until you run out of space for the parts. :) With 600Ah of 12v battery (7200Wh) and an average of 5 hours a day of sunlight you're going to need about 1500w of panels to charge that up in 1 day, or 140a of SCC capacity @ 12v nominal, 75a at 24v nominal.
Perfect so I could use three of this set up. Would you run the three set of output cables separate to the batteries or through bus bars then to the batteries IE three positive to one and three Neg to another .then only one cable from each to the batteries.less clutter.can you combine the power out .
 
Personally I would take everything to bus bars just because you're going to run out of bolts real quick otherwise. All the batteries should go to the bus bars, the inverter feed from the bus block, and all the SCC's to the same blocks. If you're running out of space on the bus bars you can go with multiple blocks and just connect them with a crazy fat wire.

Something similar just came up in another thread recently, it's got a good diagram over there too.
 
Personally I would take everything to bus bars just because you're going to run out of bolts real quick otherwise. All the batteries should go to the bus bars, the inverter feed from the bus block, and all the SCC's to the same blocks. If you're running out of space on the bus bars you can go with multiple blocks and just connect them with a crazy fat wire.

Something similar just came up in another thread recently, it's got a good diagram over there too.
Can you recommend a good 1500w or more controller for 12v might be cheaper that way my controllers are 202 pound each for 520w
 
1500w on a 12v system is tough because you need over 125a of SCC and they tend to top out at 100a, so right out the gate you're needing at least 2 SCC's to get that much amperage. If you're dead set on a 12v system it's going to be tough. There is only really 1 way you could go to achieve this with the 520w panels you have listed above:

New 100a MPPT controller with 2s panels = 100VoC @ 10.4a =1040w @ 12v nominal = 87a
Current controller and 1 panel on existing MPPT controller = 50VoC @ 10.4a = 520w @ 12v nominal = 43a

Total 1560w theoretical power production.

I'm a fan of EPEver as it's not as sketchy as PowMr/Tenmank but not as stupid priced as Victron/Outback/etc. It does the job of turning solar DC into battery DC and that's all I want it to do.
 
The midnite classic 150 controller is 96amp @ 12v so am I right in saying I can put 1152w into this I've read these are one of the best
 
Cheers guys but still a bit confused I guess I'm looking at an exact answer. How many watts in my panel solar array in parallel should I put in to this controller to make it work the best with my 12v set up. IE how many panels at how many watts.
I have the same Epever controllers, 3 of them. Manual says that you can over panel them with a 12 volt system to 1560 watts. At 12 volts you can only do that as long as you stay below 150 volts and 40 amps. Your system will not be able to use or convert anything over 520 watts but it will produce more energy in the less than ideal conditions in the morning, evening and cloudy days. Just fyi, that unit is a dual voltage controller. It will do 12 or 24 volts. Ideal thing would be to change to 24 volt system by changing your inverter. Then your setup would be producing or could handle 40 amps at 1040 watts on the 24 volt system. You could also over panel to 3120 watts as long as you stay under the 40 amps and 150 volts max.
 
The midnite classic 150 controller is 96amp @ 12v so am I right in saying I can put 1152w into this I've read these are one of the best
Very high quality, you just pay for it. Same with Victron or Outback. Personally I've never wanted all the wizzys and gizzys and online tracking and bluetooth and car washing and dog grooming that the name brand stuff charges for. All I want it to do is turn PV power into Battery power without catching on fire and EPEver, Renology, HQST and the like do that for 1/3 the cost.
 
On paper it should handle 6000w on the input,
Why do you say this? There is nothing on paper (or anywhere else) that makes any attempt to indicate that it should handle 6000W on the input. Most SCCs have three values. Wattage (input), max PV input voltage (input), charge current (output). Those three values are clearly stated as 520W, 150V, and 40A respectively. Since it clearly states 520W input then obviously it's not stating it should handle 6000W.

the traces and electronics inside can handle up to 40a before they get so hot they melt and catch fire.
No need for the fear mongering. The SCC will output no more than 40A and whatever the current battery charge voltage is. You can safely over panel the SCC. If the panel array has the potential to provide more power than the SCC can make use of then the potential extra power simply isn't used. For example, let's say you put 700W of panels on this controller (that's actually fine). Under many solar conditions the panels can only make 500W or less. But let's say it's a good day and potentially the panels could produce the full 700W. If the battery is charging at 14.4V it will only take 576W from the panels because that will provide the maximum 40A. Remember, the panels don't force 700W into the controller. The controller only takes what it can use.
 
Yup, totally makes sense if you're not familiar with how the controller is trying to work. On paper it should handle 6000w on the input, it's the output that's gonna light off if you do that thought
I stand by my statement. "I was given this thing that says 150 volts and 40 amps. That's 150*40, right? Cool! 6000 watts!"

"I can run this Harbor Freight 5000w inverter from my car battery? Cool!"

"300 watts of solar panel should produce way more than 120 watt hours in a day. Cool!"
 
I have 1500 watts of panels connected to a 150/60 CC with no issues
I think?
 
I have 1500 watts of panels connected to a 150/60 CC with no issues
Without knowing your battery bank voltage that doesn't mean too much. At 12V you are 100% over paneled. At 24V you are spot on. At 48V you could double your panels.
 
Without knowing your battery bank voltage that doesn't mean too much. At 12V you are 100% over paneled. At 24V you are spot on. At 48V you could double your panels.
!2 volt
1200Ah Lead Axid
 
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