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Post by Admin on Nov 7, 2018 20:41:04 GMT
Bench test: "Reported/LCD V" = "Supply V" 12.0 = 12.12 12.5 = 12.65 13.0 = 13.18 13.5 = 13.70 14.0 = 14.20 I adjusted the supply V slowly to where the LCD just changed the tenths to the next digit assuming this would be the minimum rounding. The SupplyV was measured on the CC battery terminals. The voltage discrepancy is a fixed percentage on the Rover's LCD reporting, reportedly .2V max. -Renogy Team |
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Post by tattoo on Nov 7, 2018 21:21:14 GMT
The voltage discrepancy is a fixed percentage on the Rover's LCD reporting, reportedly .2V max. -Renogy Team That's what I have found to be the case when I looked today..... I ain't worried about it........... |
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Post by swampmonster on Nov 8, 2018 3:48:59 GMT
Friends, there was a little lesson I learned the hard way back on my first submarine...A lesson that almost cost all of us our lives.
.........And that lesson was to "Trust your indications", because indicators were all we had when submerged for months at a time....It can be really easy to talk yourself into ignoring fault indications, and then end up in a non recoverable spiral to the ocean bottom, or serious, expensive damage to your equipment.
You, OP, noticed the discrepancy and came here to ask......And the answers you got were absolutely no help....That is the typical behavior of a crew of shipwrecks, and sadly reinforced by the ship's designer.
So OK, you have noted a high level of difference from the CC reading and the actual bank values, and all here ran you around in circles where even the admin guy finally shows up and sez, "ignore it, it is in the specs of that CC to indicate THAT inaccurately."
Well, Friend...before you accept that remind yourself that if the charge controller cannot ACCURATELY monitor battery voltage, it cannot accurately charge and maintain it.....Myself, I have 4 separate indications all lined up in a row on the wall that indicate batt voltage...1 is my Bogart Trimetic, 2 are Blue Sky controllers, and my Aims inverter remote panel.....They all read EXACTLY the same voltage, and that voltage checks with my Fluke VOM....And funny thing is they all sense battery voltage at different points in my system...so the fact they read exactly the same tells me my system doesn't suffer from any high resistance connections or undersized wiring....and also my equipment has very tight tolerances and decent calibrations.
If your system indicated LOWER voltage at the battery, then you should investigate first your connections and wire sizes, huh? But that is not the case, nope. You battery indicates higher voltage than your charge controller, so there is either a problem with the controller or it has VERY sloppy specs.
Odds are you can seek out fellow campers in your hood and compare your system reading to theirs.
You are MOST correct to investigate the issue fully.
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Post by tattoo on Nov 8, 2018 4:34:42 GMT
Myself, I have 4 separate indications all lined up in a row on the wall that indicate batt voltage...1 is my Bogart Trimetic, 2 are Blue Sky controllers, and my Aims inverter remote panel.....They all read EXACTLY the same voltage, and that voltage checks with my Fluke VOM.... And funny thing is they all sense battery voltage at different points in my system...so the fact they read exactly the same tells me my system doesn't suffer from any high resistance connections or undersized wiring....and also my equipment has very tight tolerances and decent calibrations. LOL How can you have your CC connected in different places? I really doubt that all of your systems have the exact same readings.... Since you have 3 separate systems... But I have seen your math so it could be.....
There is nothing wrong with my system and I'm not chasing ghosts....
But it's your story, sorry for the interruption...
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Post by tattoo on Nov 8, 2018 4:47:04 GMT
and also my equipment has very tight tolerances and decent calibrations. In you pic of your setup I see two CC that only read 12.7 no 100ths and two other digital displays that are 12.7 no 100ths, Yep I agree that's just decent at best.... |
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Post by swampmonster on Nov 8, 2018 9:14:04 GMT
and also my equipment has very tight tolerances and decent calibrations. In you pic of your setup I see two CC that only read 12.7 no 100ths and two other digital displays that are 12.7 no 100ths, Yep I agree that's just decent at best.... Tell me, Tatt Does your CC read .2 volts different than your batt bank? |
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Post by swampmonster on Nov 8, 2018 9:36:45 GMT
Myself, I have 4 separate indications all lined up in a row on the wall that indicate batt voltage...1 is my Bogart Trimetic, 2 are Blue Sky controllers, and my Aims inverter remote panel.....They all read EXACTLY the same voltage, and that voltage checks with my Fluke VOM.... And funny thing is they all sense battery voltage at different points in my system...so the fact they read exactly the same tells me my system doesn't suffer from any high resistance connections or undersized wiring....and also my equipment has very tight tolerances and decent calibrations. LOL How can you have your CC connected in different places? I really doubt that all of your systems have the exact same readings.... Since you have 3 separate systems... But I have seen your math so it could be.....
There is nothing wrong with my system and I'm not chasing ghosts....
But it's your story, sorry for the interruption...
I'll type slow cause I suspect you don't read fast...OK? That picture shows just my main solar system. That system employs 2 charge controllers paralled into one 4 cell bank...That bank is connected series/parallel...So one CC is connected to one series pair and the other CC to the 2nd pair, but in that old pic only one CC is fully connected because was completing the install, so it reads 0....The batt disconnect was open in that pic, so inverter screen is blank.....It's a quazy dual system where only the bank and Trimetic and inveter are the common components, so call it two system if you want. My other, or call it my 3rd system, is a totally separate system for my house batts with it's own CC, Trimetic, inverter, converter, so it ain't in the pic and it is 20 feet away.....But funny thing is all it's components read exactly the same between them....Hmmmm, must be I did something right, huh?...like quality equipment selection and installation, maybe? |
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Post by playersz28 on Nov 8, 2018 11:51:27 GMT
Friends, there was a little lesson I learned the hard way back on my first submarine...A lesson that almost cost all of us our lives. .........And that lesson was to "Trust your indications", because indicators were all we had when submerged for months at a time....It can be really easy to talk yourself into ignoring fault indications, and then end up in a non recoverable spiral to the ocean bottom, or serious, expensive damage to your equipment. You, OP, noticed the discrepancy and came here to ask......And the answers you got were absolutely no help....That is the typical behavior of a crew of shipwrecks, and sadly reinforced by the ship's designer. So OK, you have noted a high level of difference from the CC reading and the actual bank values, and all here ran you around in circles where even the admin guy finally shows up and sez, "ignore it, it is in the specs of that CC to indicate THAT inaccurately." Well, Friend...before you accept that remind yourself that if the charge controller cannot ACCURATELY monitor battery voltage, it cannot accurately charge and maintain it.....Myself, I have 4 separate indications all lined up in a row on the wall that indicate batt voltage...1 is my Bogart Trimetic, 2 are Blue Sky controllers, and my Aims inverter remote panel.....They all read EXACTLY the same voltage, and that voltage checks with my Fluke VOM....And funny thing is they all sense battery voltage at different points in my system...so the fact they read exactly the same tells me my system doesn't suffer from any high resistance connections or undersized wiring....and also my equipment has very tight tolerances and decent calibrations. If your system indicated LOWER voltage at the battery, then you should investigate first your connections and wire sizes, huh? But that is not the case, nope. You battery indicates higher voltage than your charge controller, so there is either a problem with the controller or it has VERY sloppy specs. Odds are you can seek out fellow campers in your hood and compare your system reading to theirs. You are MOST correct to investigate the issue fully. The 0.2V isn't that big a deal as long as it is doing it's thing correctly internally. Unfortunately there's no way to know that. Reading the battery voltage is pretty much the simplest thing the CC has in it's list of tasks and it can't do it correctly. I'll keep an eye out for other SRNE/EPSolar units in my travels and see if they are the same. Not sure which is the main maker of Renogy units. It is what it is but a simple question got turned into a multi post fiasco. This horse is long dead. |
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Post by tattoo on Nov 8, 2018 12:47:37 GMT
.Hmmmm, must be I did something right, huh?...like quality equipment selection and installation, maybe? Yea Hummmmm, So far I haven't been impressed at all with Blue sky products....
Installation isn't bad...
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Post by tattoo on Nov 8, 2018 12:50:34 GMT
Does your CC read .2 volts different than your batt bank? Close.... Since you also read slow I'll post it again..... Now read it slow....
Nov 7, 2018 15:23:46 GMT -5 tattoo said:
Alright..... Here you go, I just checked while it's charging and the batteries are at 14.35 and the CC says the batteries are at 14.54...
Like I said before there is nothing wrong with your CC....
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Post by tattoo on Nov 8, 2018 13:00:23 GMT
The 0.2V isn't that big a deal as long as it is doing it's thing correctly internally. Unfortunately there's no way to know that. Reading the battery voltage is pretty much the simplest thing the CC has in it's list of tasks and it can't do it correctly. I look at the difference in voltage like I look at the SOC that's on the CC....
Is it ever accurate? No
Is it helpful? No Does it bother me? NO
As long as my CC keeps my batteries fully charged that's all I care about...... And it does and has been doing just that for over a year...
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Post by swampmonster on Nov 8, 2018 18:01:06 GMT
The 0.2V isn't that big a deal as long as it is doing it's thing correctly internally. Unfortunately there's no way to know that. Reading the battery voltage is pretty much the simplest thing the CC has in it's list of tasks and it can't do it correctly. I look at the difference in voltage like I look at the SOC that's on the CC....
Is it ever accurate? No
Is it helpful? No Does it bother me? NO As long as my CC keeps my batteries fully charged that's all I care about...... And it does and has been doing just that for over a year...
SOC with any charge controller is garbage unless the device incorporates a shunt and it is wired properly, yours does not. You may have a shunt and separate meter to assist you and I hope you do, where alas you properly know to ignore the SOC on the CC, but you are most wrong to accept the disparity in voltage readings... No quality CC, when wired correctly, will indicate that wide an error....And when confronted with that error, no quality device maker will explain it away so simply as folks here allowed. Like the OP sez, voltage readings are the very simplest task any CC has to perform...Trouble is, that same CC then uses that measurement to do it's hard work where it's logarithms require precise input to deliver precise output...In my mind, if a particular CC can't accurately measure voltage, then it also can't accurately control it....Kinda a garbage in garbage out thang, yaknow? But that is just me, and that is the way I think. A separate problem is when folks man the battle line to defend their selection of inferior equipment even when they too acknowledge that it is lacking. It's a shame that often these forums turn into a brand loyalty driven, and "I don't wanna admit I made a bad choice" typa thing. I ain't here to piss on anyone's sneakers, just to share what I have learned and also perhaps learn more....Don't you think it's ironic that a free Harbor Freight DVM reads more accurately than an expensive CC? |
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Post by tattoo on Nov 8, 2018 18:32:00 GMT
No quality CC, when wired correctly, will indicate that wide an error....And when confronted with that error, no quality device maker will explain it away so simply as folks here allowed. So you really think that the battery voltage can keep up with the voltage going up and down like the CC can? You really are stretching it....
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Post by bupkis on Nov 8, 2018 18:36:51 GMT
This lengthy blog goes into depth on the ways of battery monitors. Folks do not understand them or batteries. My conclusion is I don't need it. marinehowto.com/programming-a-battery-monitor/"FACT: If you do not keep up with programming your Ah counter, on a continual basis, Ah counters do not theoretically get out of sync with your battery, they physically get out of sync with your battery. This is a real problem that does happen, not a made up problem that might happen. FACT: Ah or Coulomb Counters are very accurate at counting Ah’s but they do not track changes in your batteries health. They are simply calculators that rely on proper programming to yield a more accurate output." somewhere else he has a nice video of balance battery wiring, the smart gauge guy does a similar analysis on interconnecting batteries. Doing it right usually cost nothing. Can't wait till the OP realizes what panel voltage is when @ high freq it goes from last scan Vmp to Voc. A sillyscope can be used to see the it! |
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Post by tattoo on Nov 8, 2018 18:43:14 GMT
You may have a shunt and separate meter to assist you and I hope you do, where alas you properly know to ignore the SOC on the CC, but you are most wrong to accept the disparity in voltage readings... Nope don't have a shunt and I don't need one like the cheap CC you have.... Also I don't need an external device to tell me what my CC is doing like you need one for your Blue CC.... Mine tells me right on the CC.... Your late to the party, I've said that the SOC is BS for almost two years now, But I am glad you can see it....
My system has been running great for 2+ years now, how long have you had your system running? Be honest.... You like to talk about olden days.... So here goes, Something I learned years ago..... If it ain't broke don't fix it.....
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