Charging Issues - solar bulk charge =12.65v, alternator=14v

[thomm225]

Then after the battery is charged all the way, the voltage will go back down to your Float Setting.

If you haven't changed your Float Setting, it's probably still at default which is 13.8 volts

[john61ct]

Originally Posted by thomm225

Your battery is still charging up to float which is usually defaulted at 13.8 volts

Bulk means striving for **Absorb** voltage, usually well over 14V.

Then Absorb V is held until current drops to endAmps, bank is Full.

Then Float, after all charging stops.

The actual setpoint need to be adjusted to the profile specs given for that specific battery, can vary very widely.

[john61ct]

Originally Posted by thomm225

Then after the battery is charged all the way, the voltage will go back down to your Float Setting.

If you haven't changed your Float Setting, it's probably still at default which is 13.8 volts

The issues discussed here have nothing to do with Float.

Originally Posted by thomm225

Exactly, like I said. it's (still) charging up to float.

No. See above.

Please stop confusing people with misinformation and misuse of terminology.

[thomm225]

Originally Posted by john61ct

The issues discussed here have nothing to do with Float.

He said he was confused because his voltage was only at 12.65.

I was basically recommending that he allow the battery to charge. It's not rocket science so stop trying to make it seem like it is.

You can do word play back and forth any way you want, I put it as simply as I could. Just allow the battery to charge up to Float. In the mean time, you can monitor the charging process if you like.,

Default absorption max voltage on most Victron Controllers is 14.4. Float is 13.8.

You can monitor all this with your volt meter, your phone, or your laptop. After your battery charges completely it will drop back to your Float Setting

I have a Victron 75/15 Controller. Settings are still at default. I plan to monitor my system very closely when I sail later today. I may hook up one of my PWM Controllers and another panel to my battery bank as well. Should be interesting, but not confusing

[thomm225]

So when I got to the boat this afternoon, my system was finally back at Float. (after last weekend when it was down to 11.5) The readings were 2 Watts and 13.45 volts according to my computer.

After I turned everything on, it went to like 40 watts. Then I unplugged and sailed for 5 hours over to my new location

Looks like I'm at maybe 12.5 volts now according to my analog Altus Battery monitor which is reading 50%

[john61ct]

Originally Posted by sgtPluck

Thanks for the for the tips. Sounds like all is well, but I'm still a bit confused as the manual says:

> 1.9.1. Bulk
> During this stage the controller delivers as much charge current
> as possible to rapidly recharge the batteries.

And the bulk charging voltage according to the manual and the setting I have the controller is : 14.4v. I guess what's confusing is it doesn't say anywhere that this is the maximum voltage for this phase.

So is the explanation that the maximum current (meaning amps) would be delivered at the lowest voltage that is enough to overcome the voltage on the battery?

Before the sun came up the battery was reading 12v (low for an AGM, but there was a light trickle load on it all night so I'm not sure if that qualifies as resting voltage). So in this scenario the while-charging voltage came up from 12v to 12.65 and was putting in maximum current at that voltage.

In the first stage Bulk / CC, the charger is putting out max current trying to get the battery to that Absorb setpoint.

If amps are high that may be an hour or two.

If loads are on and/or charger amps are too low, it may never get there.

Once it does hit that max voltage, it is in Absorb / CV stage. If amps stay high, maybe only 4-5 hours left to go before getting to 100% Full.

If loads are on and/or charger amps are too low, it may never get there.

As it gets over 80-90% full (depends on current rate), still many hours from Full, amps accepted by the bank will start to drop.

endAmps is the batt maker's spec for 100% Full, can use .005C if as yet unknown, so half an amp per 100AH.

That is for a new healthy bank, old worn ones may never get there. In which case use "no further current drop for two hours".

Testing the health of the bank is best done on shore power.

[Stu Jackson]

Originally Posted by thomm225

>>>>>>>>>>>>


>>>>>>>>>>>>>>>>>>>>>>>>>


You can do word play back and forth any way you want, I put it as simply as I could. Just allow the battery to charge up to Float. >>>>>>>>>>>>>>>>>


>>>>>>>>>>>>>>
After your battery charges completely it will drop back to your Float Setting>>>>>>>>>>>>>>>>>>>>


>>>>>>>>>>

Huh?


"Charge up to float?" That makes NO sense. Countered by the "...drop back to float" item.


For those who may be new to Basic 101 battery charging, it is unfortunate that some respondents continue to mangle the, uhm, basics.


While some may choose to re-write what is already published in BOOKS about battery charging, as well as in most every single regulator installation manual and quality battery chargers, I refer the OP to those very books. I recommend reading them, first. Then compare it to some of the material shared here.


"We report, you decide."


Ach, if only I had a dime for every one of these incorrect posts.


Anyway...

[thomm225]

Originally Posted by Stu Jackson

Charge up ……...

Right, the OP's system needs to continue to charge

I'm not sure what you are having trouble understanding

The OP said his battery was at 12.65 volts and in Bulk mode. Reading was 122W so there was current flow.

His battery was still charging. (and he may have had some systems running)

If you were to monitor the battery banks charging, you would see it continue to charge in bulk mode, then absorption, and finally to Float

In Absorption mode the voltage can get as high as 14.4 volts if your settings haven't been changed. After reaching full charge, it will drop back to Float which is defaulted to 13.8 volts.

If you cannot understand this, just watch the little yellow light on the case. It might be easier for you to understand.

Blinking fast = bulk

Blinking slow= absorption

On= float

Mine is at about 12 volts now and will be going into bulk as soon as the Sun comes up. This laptop and the internet jetpack are running on battery power (internal)

[john61ct]

No one knowledgeable was misled by your misuse of the terminology.

The point is that it was likely to confuse other noobs if left to stand uncorrected.

When in Bulk, you need to keep charging

not "until Absorb is reached"

voltage is not going to "maybe get up as high as" any setpoint

It **must** hit that setpoint, often higher than 14.4V, and that is still very early stage.

It then must stay at the Absorb setpoint for often many hours.

As long as it takes to hit endAmps.

Trusting your charge sources' blinky lights is a sure path to murdering your bank

Leaving your charge sources set to their defaults the same.

[thomm225]

Wow, I sure am glad I got into this discussion. I decided to monitor my solar as it went thru the stages of charging my batteries back up to Float the am

This started at around 6:30 and the batteries were at 12.1 volts

I connected the laptop and just monitored it while I fished for breakfast.

After a while, it seemed the max wattage was 16 W. when the sun hit just right (I have two panels totaling 85W) I knew it had charged back up really slowly after last weekend so I figured something wasn't right......but I wanted to see what the exact problem was no just reset all the connections

Finally, I thru a tee shirt over the 20 watt panel and sure enough I had 2 watts even when the sun was good (on my 65 Watt panel)

I reseated the connections at the Victron and Bam!, 33 watts . Uncovering the 20 W panel and I was getting near 50 Watts by 7:45-8:00am

As far as terminology, I may talk in a bit of a slang thinking folks can follow along, but I guess I have too many years in the business of electrical, electronics, and computers.

We have 10 Large UPS units that have 48 or more twelve batteries. These "charge up to float" also.

Our newest computers have 32 gig of ram. Ridiculous. We still have drives that are around 3 gb

This solar stuff sure is fun though, but if you really want to simplify it, just leave your settings at default and watch your yellow blinking light for which stage your system is currently at if you have a Victron. I think too many people get caught up in the readings

I may order another 50 watt panel and a monitor for the Victron though

And Btw since this is a sailing forum, I got one hell of a workout this am sailing back into a NE wind and dodging ships as I tacked the channel. One Coast Guard Cutter, two container ships, and one Aircraft Carrier. I also had to sail across a shoal that on the chart I have that is 20 years old read 3' at low tide. It was near high tide and the low spot I crossed was 5' of water. I draw 4'. I couldn't sail the channel (couldn't point close enough) and didn't feel like putting the outboard in. I had sailed off anchor so I cut across thinking if I did run aground I could get off...….

[john61ct]

Just remove "up to Float" from your lexicon.

drop to Float is more like it, and should only occur after a long Absorb Hold time, and endAmps is reached.

Most default setups even with $800 controllers drop to Float way too early.

MaineSail dubbed it premature infloatulation.

Not sure any of this qualifies as slang.

[thomm225]

Originally Posted by john61ct

Just remove "up to Float" from your lexicon.

drop to Float is more like it, and should only occur after a long Absorb Hold time, and endAmps is reached.

Most default setups even with $800 controllers drop to Float way too early.

MaineSail dubbed it premature infloatulation.

Not sure any of this qualifies as slang.

I said drop to float earlier in my posts and folks still freaked out.

Charging up to float is easily understandable as slang especially as compared to a 12.1 or 12.65 volts during bulk charge

btw, sailing, running 2-3 miles, and doing a pre run workout in the same week is tough when over 60 especially after sailing the previous weekend with little sleep plus hiking/running the trails after kayaking to the beach on that trip

I ordered on of those 50 watt Renogy Panels so I'll see how it does. With my other 20 w panel that will give me 155 watts

[hellosailor]

The "proper" output of an MPPT solar charger needs to be confirmed with the maker. They ALL vary and some (like BlueSkies) are totally different from conventional three-stage chargers. A BlueSkies unit simply tries to lead the battery voltage, by about 0.4V (iirc) and maximize the amperage it can supply. You won't see the 13.8V that a dumb three stage charger (like Balmar) wants to put out, because BS knows that the battery electrolyte will bubble less, the internal resistance will be lower, and the battery will charge about 15% faster this way.
The concept of "bulk, absorption, float" was obsolete a decade ago, and still is. Like lopping off a leg to prevent the spread of gangrene, it still works, sure. But there's more elegant ways to treat the problem these days.
First, CALL THE MAKER and speak to a real techie, not just a receptionist. Find out if it is doing what it is supposed to be doing, before assuming that's wrong.
(Yeah, surprised me too. A decade ago.)

[thomm225]

Originally Posted by sgtPluck

Thanks for the for the tips. Sounds like all is well, but I'm still a bit confused as the manual says:

> 1.9.1. Bulk
> During this stage the controller delivers as much charge current
> as possible to rapidly recharge the batteries.

And the bulk charging voltage according to the manual and the setting I have the controller is : 14.4v. I guess what's confusing is it doesn't say anywhere that this is the maximum voltage for this phase.

So is the explanation that the maximum current (meaning amps) would be delivered at the lowest voltage that is enough to overcome the voltage on the battery?

Before the sun came up the battery was reading 12v (low for an AGM, but there was a light trickle load on it all night so I'm not sure if that qualifies as resting voltage). So in this scenario the while-charging voltage came up from 12v to 12.65 and was putting in maximum current at that voltage.

Your system is definitely OK.

The bulk charge voltage will pretty much (but not exactly) equal the batteries current State of Charge. (SOC). Actual will be a little less.

Example, mine was down to 12.1 volts when I got up Saturday am after running an AC Fan through my inverter all night plus my depth finder and lights at times.

Since my system at first was only working with my 20 watt
panel, the first wattage I saw was 2-4 and the battery went to 12.19 at first light and slowly charged from there.

After I got my 65 watt panel working, my battery was nearing 12.8 volts when the Sun was on the panels by around 8 am just before I pulled the anchor and sailed. The boat had ben swinging at anchor this whole time and the bow was facing the Sun so the dodger and I were blocking the panels quite a bit

I had raised both panels and aimed them toward the Sun. Before I left I laid the 65 Watt panel back down on the lazarette secured it and tied the 20 watt panel to the stern railing facing away from the Sun.

On the sail back with everything on and the autopilot working hard, I still had around 12.5-12.7 volts or 50-60 % on my analog Altus Battery Monitor which I'd guess is from the late 80's or early 90's

Your alternator is super strong as compared to your solar and could be putting out crazy high current like 35 amps on up which is why you are getting the higher readings with it on.

[sailinglegend]

Originally Posted by thomm225

.....In Absorption mode the voltage can get as high as 14.4 volts if your settings haven't been changed. After reaching full charge, it will drop back to Float which is defaulted to 13.8 volts.

If you cannot understand this, just watch the little yellow light on the case. It might be easier for you to understand.....

When a charger drops back to Float the battery is never fully charged, maybe only 90-95%.

Originally Posted by john61ct

.....It then must stay at the Absorb setpoint for often many hours.

As long as it takes to hit endAmps......

Only a a very few chargers have a shunt to see "endamps", and this is an optional extra. Most chargers rely on an "timer" to stay in absorption mode. They will never see the ideal "endamps" to show the battery is full - 0.5% of battery capacity at 14.4v - because the charger will have dropped to float long before that. It is desirable that the charger doesn't stay at this high absorption voltage this long, better to drop to float at around 2% of Ah capacity.