Trojan absorbtion voltage

[GeorgeF]

Trojan "absorbtion" voltage

Just a thought of mine:
Is it possible that because of "the stickies" here @ Solarpaneltalk that Trojan change their charge instructions (description) bulk or boost to "absorbtion voltage" ?

Forget bulk and absorb stage, it is now 1 stage CV only , go for fast and "maximum smoke" from sunrise till dawn, no more Constant Current in the charge algorithms in the solar world cause it is Constant Power and not CC

or

am I talking BS now??

It can be so confusing for users if they read the manuals of charge controllers and then the charge instructions in the battery specs. Why not uniform?

[Mike90250]

Because each mfg want's their controller to be the biggest, fastest and sound more impressive, so they invent bigger names for mundane things..

[Sunking]

am I talking BS now??

Mostly BS. Trojan did not change, the user group changed. For decades Trojan and other battery manufactures made batteries for golf cart and other traditional users. Then the solar fad started and fools started using batteries to store power for night use. Warranty claims went through the roof because users do not know how to care for batteries. They fail to understand solar in not capable of fully charging a Pc battery as there is not enough sun hours in a day to recharge a battery. So their batteries are in a chronic state of under charged and fail quickly. Users fail to buy a generator and top off their batteries once or twice a week with a good long 12 to 24 hours on a generator.

Second part of this is solar users seem to think charge controllers use the same algorithm as a commercial AC charger which is false and not even remotely possible and users should clearly understand why. Example most of you think a solar charge controller is Constant Current and Constant Voltage. That is impossible. Only way to generate a CC/CV algorithm is with a stiff source like a generator or commercial AC with unlimited power and time. Now I know there are going to be the Ampsters come along and say BS. Ignore them because they do not know what they are talking about.

A Solar Charge Controller algorithm is limited power aka Constant Power and Constant Voltage. A soar panel power is dynamic changing every single second of a day. It can only generate full power for just a few minutes around solar noon. If you were to watch the current is all over the place, absolutely nothing CONSTANT about it. All you have to do is understand Ohm's Law to know I speak the truth.

So the battery manufactures know all this. So for solar users they have to change the algorithm to maximum smoke to force your panels to generate maximum power form sun rise to sunset knowing full well the battery will rarely ever be fully charged unless you have a generator to charge up your batteries at least once a week. It takes 12 to 24 hours to fully recharge a battery. At best in summer in a few locations might have 6 to 7 Sun Hours to work with. Not near enough.

So as a consequence off grid solar users end up paying 4 to 10 times more for electricity the rest of their life, and become very heavy polluters in the process because batteries have a negative EROI and half the energy is thrown away with the garbage.

[GeorgeF]

Is it possible to make from EVERY MPPT charge controller a one stage CV (float)charger ?

[Mike90250]

You make a float charger by simply using the right wattage PV panel for your battery size, wire it up with a blocking diode. Done.

100ah battery, needs a PV panel of about 2-3A at the float voltage. This only does FLOAT, it won't recharge a low battery

[GeorgeF]

What I mean is "floatcharge" with the a voltage setpoint just below the gassing voltage for lead acid from morning till dawn, CV charge only, no more stages bulk+absorb.

[Mike90250]

Don't use industry standard words or phrases to mean something other than the standards. Call it "Georges Non Gassing Voltage".

When most solar professionals say float voltage, we mean the temperature adjusted voltage the battery mfg states to use for your application ( cycle or standby duty ). Stray from that, and you risk your batteries longevity.

If somebody comes along and says, hey George figured it out, and I'll simply do what he did, they are likely going to be VERY unhappy with the results.

[Sunking]

Is it possible to make from EVERY MPPT charge controller a one stage CV (float)charger ?

Absolutely. Just set Bulk = Absorb = Float. That easy.

[GeorgeF]

There is guy who did this (set same voltage for bulk, absorb, float) and he claims that his MPPT automaticly adjust the voltage "setpoints" for these two stages.

What do you read in this screenprint? The terminal voltages during charge and not the charge (setpoints), am I right?

[Mike90250]

That screenshot is incomplete, but with the 2 different modes listed (CV & CC ) and the different voltages, it is not set Bulk=abs=float.
Seriously, " A Guy " ?? He's incorrect if he thinks he set things that way. He may have attempted, but has failed

[GeorgeF]

Despite of his "dangerous" DIY lithium pack we will continue to evaluate, he reported as follows:
Lithium 13S x 3.7v = 48.1v
Setpoint 52.8v, 4.06 per cell

His setting 13.2v which, according to him, automatically be multiplied by his MPPT to 52.8v (Screenprint hereunder)

In the screenprint posted above one can clearly see that the battery voltage already reached the setpoint of 52.8v. Panel PV input is also higher, so not much current to "push" in the battery, but still more than 500w of charge power.......

So, although he filled in the same voltage in the 3 fields his MPPT reports stages CC & CV. But I do not think that his MPPT adjust the setpoints. Do you?

[GeorgeF]

Here is his full settings

[Mike90250]

If this is for Li batteries, stay away when the flames and smoke starts. you can't pretend you know what you are doing, when dealing with Li, you will get a wake up dose of reality.
Only reason the voltage would change on a genuine charger, is when the temperature compensation kicks in to keep the battery charged properly. Li does not use temp comp.

I'm not going to debug this mess any further

[GeorgeF]

Made a thread before already about those DIY Li guys who think they are PE, Battery expert and Prof Dr Phd at the same time
https://www.solarpaneltalk.com/forum...-not-dangerous


Was just curieus how is it possible that his MPPT reports CC & CV while he filled the same voltages in the three fields boost, float and absorb(CV)

[Ampster]

.........

Was just curieus how is it possible that his MPPT reports CC & CV while he filled the same voltages in the three fields boost, float and absorb(CV)

Part of the answer is that the word beginning with a "b" is the same thing as Absorb and both are the same as CV. My preference is for the term Constant Voltage because it actually describes what the charger is doing.
My charge controller reports existing voltage. That is separate than the CV voltage setting that it reports, and different than Constant Current that it reports.
I appears from the pictures you posted that it is a 13S Lithium pack of NMC like chemistry.

My answer is more of a question to try to clarify the terms and distinguish between a setting and a measured voltage. The term "reports" is ambigous.