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gcrank1
Member
# Posted: 6 Apr 2021 10:03
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It charges that high for bulk, like after a night of draw-down from whatever you have running and no charging. Same as your car, start it up and the voltmeter goes to 14.6ish to replenish the heavy starter draw, then settles.
Once your solar switches to absorb it lowers and when into float even lower, like what you see at 13ish. Give it a heavy load/draw-down and you should see the meter peak toward or to your preset 14.6.
Is this LFP? If so, from what Im seeing Id tune that peak back to 14.4, abs to 13.2?, no equalize and no float.

paulz
Member
# Posted: 6 Apr 2021 10:44
Reply 


Yes, LFP. I had to program the new CC (Epever Tracer BN) as there is no setting for LFP like the old Renogy I had that died. I used the parameters that Battle Born lists for LFP and the Epever.

https://battlebornbatteries.com/setting-up-the-epever-solar-controller/

Over Voltage Disconnect 14.7 V

Charging Limit Voltage 14.6 V

Over Voltage Reconnect 14.6 V

Equalize Charging Voltage shut off or 14.4 V

Boost Charging Voltage 14.6 V

Float Charging Voltage 13.6 V

Boost Reconnect 13.3 V

Low Voltage Reconnect 10

Under Voltage Warning Reconnect Voltage 11.5

Under Voltage Warning 11.5

Low Voltage Disconnect 11.0

Discharging Limit Voltage 10.5

Equalize Duration 0 or set as low as possible

Boost Duration 180 minutes

gcrank1
Member
# Posted: 6 Apr 2021 12:40
Reply 


Iirc you are in the right zone, though I think over on Diysolarforum some have said not to go for 100% @ the 14.6 but kick that back to 14.4 (95%?) which will be better for bat health/life?
Anyway, Im inclined to go conservative on most things.
Just remember, a 'fully charged battery' wont show it is taking much, or any, amps in on the readout. That throws some off thinking their system isnt working when in fact it is because everything is charged up.

paulz
Member
# Posted: 6 Apr 2021 16:04 - Edited by: paulz
Reply 


Yeah I think you're probably right on kicking down the max charge. Like I said though, I have not seen it go that high recently. I think when it did was before I put those 6 more panels on the roof and the batteries were getting drained more than they do now. Even after all day cabin use now it doesn't go over about 13.6 so the 14.6 max is not coming into play from what I have seen.

I have 18 260 watt panels going now, but usually no more that a half dozen getting sun. Works great so far but if they were to magically all get sun at the same time it'd probably blow the cabin into orbit!

paulz
Member
# Posted: 17 Jun 2021 22:08 - Edited by: paulz
Reply 


Uh oh. Went down to the shop this evening to a red flashing light on the SCC meter (MT50). It was an extremely hot day today. This system is using 4 FLA marine batteries, and I do have the temp sensor in place (obviously). I didn't use any juice in the shop all day. I left it as is, I guess the plan is to go down in the morning and hope it's back to normal, check the water and maybe get more air around the batteries. Sound good?

Just when things were running seamlessly.
20210617_1835251.j.jpg
20210617_1835251.j.jpg


paulz
Member
# Posted: 18 Jun 2021 14:18
Reply 


Thanks for your concern.

Got down there this morning, red light off, 14.2 battery voltage, plenty of water in the cells. Nothing about it I could find in the manual, guess it's just a warning, probably cuts off charging. I created a little more air space around the batteries. Another scorcher today, we'll see. Funny that these batteries can sit under the hood of a vehicle with a hot engine and that's presumably OK.

paulz
Member
# Posted: 18 Jun 2021 16:15
Reply 


Red light back on. 90F outside, hit the batteries with the infrared temp gun, 84-86F (shaded).

Manual says this:
 Battery Overheating
The controller detect the battery temperature through the external temperature
sensor. If the battery temperature exceeds 65ºC, the controller will automatically
start the overheating protection to stop working and recover below 50 ºC.

50C is 122F. Temp sensor must be off.

paulz
Member
# Posted: 18 Jun 2021 16:34
Reply 


I have another temp sensor but it looks like this. The one I have on there is square and had double stick tape. Not sure how you are supposed to attach this one.
Screenshot_2021061.png
Screenshot_2021061.png


ICC
Member
# Posted: 18 Jun 2021 16:43
Reply 


The batteries themselves can get hotter than the ambient air temperature. Heat is produced when a battery is charged. All types of batteries.

ICC
Member
# Posted: 18 Jun 2021 16:47
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Quoting: paulz
Not sure how you are supposed to attach this one.


Dip in a cell. Just tape it to the side of a battery. It may not work as thermocouples are made with different characteristics.

Do you have an IR thermometer?

paulz
Member
# Posted: 18 Jun 2021 16:51
Reply 


Ha, I was wondering about drilling a hole..

Yes I do, see a couple post above. They are at 84-86F.

Steve_S
Member
# Posted: 18 Jun 2021 17:39 - Edited by: Steve_S
Reply 


That PROBE sensor should be attached at mid height, mid width attached to a battery with good tape on the centre inside of your bank. Do not think of sticking it inside a battery.

To clarify, if you have 4 batteries, 2x2.
[Batt-1][Batt-2]
[Batt-3][Batt-4]
You would put the sensor at the point where all 4 meet.
OR between Batts 2&4 taped to the side middle of one of the batts.

The batts get hot while charging, so use a good tape like that red sealer tape for Tyvek house wrap, it doesn't mind the heat.

BTW, 311 posts in just a few days under a year on this thread.... hahaha... hmmm.

paulz
Member
# Posted: 18 Jun 2021 18:18
Reply 


This thread represents me going from a no nothing to the solar wizard I am now..

Thanks to the help of all you guys.

As I recall, the sensor is not compatible with LFP batts. Why?

Steve_S
Member
# Posted: 18 Jun 2021 19:50
Reply 


LFP does not use Temp Compensation like lead.
The temp monitoring by a BMS is for operational temperature ranges. For example, no charging if cells are below freezing or if too hot, but discharge is ok to -20 celsius etc...

gcrank1
Member
# Posted: 18 Jun 2021 20:42
Reply 


I just cant seem to think in C.....

paulz
Member
# Posted: 19 Jun 2021 10:58 - Edited by: paulz
Reply 


I know what you mean. I just recently realized 40F is 4.5C, I had been running my cabin fridge at 7C. It has a F option, but I would have to read the 200 page instructions to figure it out.

Anyway, swapped out the temp sensor last night, all good so far. Heat wave has subsided so won't know again until hopefully August or Sept.

ICC
Member
# Posted: 19 Jun 2021 11:07 - Edited by: ICC
Reply 


Using a scale where water freezes at 0 seems to me to make more sense. Weights and lengths, etc. etc.

Note: I corrected the typo errors I made when using my phone w/o proofreading after FishHog quoted me. Someday I may learn to slow down. Maybe

FishHog
Member
# Posted: 19 Jun 2021 12:55
Reply 


Quoting: ICC
Using a scale ehere eater freezes


Exactly

Having been raised at a time where they switched us in public school from Imperial to metric, I'm fairly bilingual. But for some reason I like F above freezing and C below. Just to really mess up my wife.

ICC
Member
# Posted: 19 Jun 2021 16:52 - Edited by: ICC
Reply 


I have friends in several other countries. Of course they use the metric system. I have spent time visiting in some of those countries. I learned to relate to the metric system and relate well to both. I found it relativly easy. But then I can converse in English, Spanish, Diné and some French without needing to think in one and mentally translate.

Steve_S
Member
# Posted: 20 Jun 2021 06:06 - Edited by: Steve_S
Reply 


General FYI for the Metrically Challenged.

IF you have Windows 10, the calculator has Many Modes, including Length & Weight conversions that make it easy to figure out. I dunno about Apple products but my Raspi has a tool for it too. Phones vary and may or may not.

Nobadays
Member
# Posted: 20 Jun 2021 08:20
Reply 


Funny how a thread about "general solar questions" could slide so low to become an American bashing thread....

Come on... let's keep it friendly!

ICC
Member
# Posted: 20 Jun 2021 21:02
Reply 


Funny how a thread about "general solar questions" could slide so low to become an American bashing thread....

Come on... let's keep it friendly!


Yes, it is funny sometimes to see how a thread can wander way off the OP.

Was the "American bashng" reference to my comments? I am sorry if my comments were taken as "American bashing". I didn't think anything I stated was unfriendly.



GM, Ford and Chrysler/Dodge began metrification in the 70's. Those companies did their conversion over decades. They concentrated on making the change whenever a new component was designed. They did the conversion at less cost than initially estimated and in some cases actually saved money over that transition period. Some of the money spent in the US to train emplyees about the metric system was made back by not having to train people in metric countries about the Imperial system. Many cars and trucks were a mishmash of Imperial and metric fasteners during the conversion.

John Deere, Caterpillar, IBM, Xerox also did conversions to metric in their US facilities around that same time. The list of American companies that use metric in their design and manufacture is extensive. Apple has used metric screws for over a decade. American Tesla has been metric since its origination in 2003. Those companies, and others, have been metric for years, they simply have not told Americans. Ever wonder why Coca-Cola changed their 16 oz. size container to be 16.9 oz? 16.9 oz. converts to 499.79 milliliters, as close to an even 500 ml, or half a liter, as you can get w/o using 2 decimal places for the US ounces (16.91 oz.). The label even states it is 500 mL. All the soft drink companies have sold 1 and 2 liter sizes for decades. Metric. The pharmaceutical industry has been metric for decades; 375 mg tablets of Tylenol anyone?

paulz
Member
# Posted: 20 Jun 2021 22:12
Reply 


Wasn't you and it got edited, all good. Didn't bother me since I don't understand big words.

My '83 Chevy Blazer is half metric. Pain in the rear to work on. Double the tools, and careful not to put one in another's threaded hole.

Tires, of course, are half and half. 275/75/16 for example. The 275 in mm and the 16 inches.

Nobadays
Member
# Posted: 20 Jun 2021 22:14
Reply 


Quoting: paulz

Wasn't you and it got edited, all good.


ICC
Member
# Posted: 20 Jun 2021 22:36
Reply 


Well thank you. I am relieved. And happy.

GM's first all metric car was the Chevette. Maybe being the first all metric was the best thing about it

scott100
Member
# Posted: 20 Jun 2021 22:45
Reply 


Didn't notice any bashing in this thread. FWIW, as a US citizen I've been using the metric system for years. It's second nature for those of us who worked on cars and later worked in research support in a university setting. Measurement of length, distance and fluids is easy to go back and forth. Temperature not so easy unless you have a feel for it. I do know that when it goes much lower than 0 C, it's time for us to pack up and head back south to SC in the fall.

paulz
Member
# Posted: 11 Jul 2021 15:57 - Edited by: paulz
Reply 


Wow, so my system voltage generally stays between 13.0 and 13.7 at the cabin with LFPs. This morning I noticed it at 12.9 briefly. I have been running the fridge colder and voltage will kick down a couple tenths when it runs. Charging amperage stays under 10.

Today, mid sunny day, I decided to charge my Li chainsaw battery, using the AC charger through the inverter. Before flicking it on I checked the meter and saw battery voltage at 14.4 iirc. No big deal, it goes that high sometimes, recovering from overnight I figured.

When I turned the inverter on and plugged in the chainsaw charger the amperage rose to almost 30! I had never really noticed a correlation between charging input and load but I guess this proves it's there, provided you have the panel input to do so. Apparently I do, and will have to be careful I don't exceed the 40a max of my SCC.

I turned the inverter off and panel went back to the usual readouts. I still find the correlation between all these amps, volts, supply and load confusing, hopefully the fuses and safeguards built into the equipment keeps me safe until I do.
20210711_123909.jpg
20210711_123909.jpg
20210711_123719.jpg
20210711_123719.jpg


Steve_S
Member
# Posted: 11 Jul 2021 19:15
Reply 


I run my system with Float on the batteries for them to balance out gently, once they are full maybe only 1 or 2 amps is going into the battery bank. The SCC may have an output of 8 amps because the inverter is supplying power to the house. If I turn on my Coffee maker which will draw 47A, and there is enough solar capacity, the SCC will deliver that without pulling anything from the batteries, as soon as the coffee maker is done, the Amps produced drops back to 8A.

If your SCC is rated for 40A that's all it will deliver, now if you put something on that demanded 50A the SCC would deliver the 40A it is capable of and the batteries would back fill the rest. Once that load is done, then the SCC will deliver what it can to recharge & top off the batteries.

13.0V = 3.250Vpc
13.7V = 3.425Vpc (Full working voltage)
14.4V = 3.600Vpc (overfull above the working knee)
14.1V = 3.525Vpc Optimal Bulk Cutoff voltage
13.95V = 3.487Vpc Ideal float voltage

paulz
Member
# Posted: 12 Jul 2021 06:18
Reply 


Thanks Steve. OK the amp delivery makes sense now.

You have a 47 amp coffee maker? Supplying the whole neighborhood, lol?

Steve_S
Member
# Posted: 12 Jul 2021 06:32
Reply 


Oster PSTX Series coffee maker with thermal carafe, no warmer plate.
https://www.oster.ca/en_CA/coffee-and-kettles/coffee/oster-10-cup-optimal-brew-therma l-programmable-coffeemaker-stainless-steel/BVSTPSTX95-033.html

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