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Looking for Synonyms

The "Bulk" of the charge is forced in at a high current.
Then the remainder of the charge is "absorbed" at a lower current. (Similar to batteries in parallel equaling with each other)
That is how I understand it to be.
So if the battery voltage reached during the bulk stage is for example 13.8, what should the voltage applied during the absorption stage be, and for approx. how long? (135AH battery)
 
I would set bulk to 14.4v.
And absorption to 13.8v.
How long, would depend on how much solar you have and what your loads are doing to the SOC.
 
I would set bulk to 14.4v.
And absorption to 13.8v.
How long, would depend on how much solar you have and what your loads are doing to the SOC.
That is very close to what my DC-DC charger comes set at. (Bulk 14.4, Absorption 14.0)
The battery manufacturer specifies 14.6V charge, but for the sake of longevity, lower is my pick. They also do not specify any absorption figure for some reason.

I read somewhere that lowering the bulk to a more conservative figure would extend the charging time required to get to full charge, is that correct?
 
13.8 is 100% SOC. (This is the rested voltage)
Charging at 13.8v , let's the battery get there at its own pace. Higher voltage forces power into the battery faster.
 
I'll settle for that for now and hope it all goes well.
Thanks to all for your input, much appreciated. :)
 
Charging a battery is like returning a boat.
You can come in fast. But as you get close you have to slow down and ease your way in, the last bit.
 
What were the default settings? That will tell you which is which. They were probably set to Lead Acid. Bulk is always highest. It should be around 14.3 to 14.6, regardless of chemistry. Absorption is always lower and is going to be somewhere between 13.4 and 13.8. Float is what is left. Look at the numbers and then translate the terminology to whatever you like.
 
What were the default settings? That will tell you which is which. They were probably set to Lead Acid. Bulk is always highest. It should be around 14.3 to 14.6, regardless of chemistry. Absorption is always lower and is going to be somewhere between 13.4 and 13.8. Float is what is left. Look at the numbers and then translate the terminology to whatever you like.
I disagree. Bulk is everything the controller can give until it hits the absorption setting i.e. 14.8 volts, after which constant voltage is held, allowing the battery to top off. Once the timed or minimum current setting is met in Absorb stage the controller transitions to float, holding the voltage at 13.6 for example. Then the sun sets and batteries will settle down to 12.8 or so (fully charged resting voltage)
 
I have only two available (relevant) settings, they being Constant Voltage, and Boost Voltage (timed)
I think that the setting called "Constant Voltage" on my charger, is where I can define the voltage reached during the constant current stage of charging, at which point the charger goes to stage 2 which is the constant voltage stage (timed) but they are calling it "BOOST"
Yes that is likely the scenario. Most chargers and charge controllers do not have an adjustment for current.
 
Yes
A lower voltage will push less amperage
Do you mean less Amphours?. My fixed current chargers push the same current regardless of the voltage setting. The current remains the same throughout that stage. That is why it is known as Constant Current.
 
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Am I correct in thinking that the only stage that should be timed is constant voltage?
Yes Constant Voltage (often called Absorb) can be a timed stage or one the shuts off at a ending Amps setting. That contradicts my earlier statement but the key term for those that have that setting is “ending Amps“ or something similar. Minimum Current is another term that is used.
 
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Do you mean less Amphours?. My fixed current chargers push the same current regardless of the voltage setting. The current remains the same throughout that stage. That is why it is known as Constant Current.
This is referring to the CV stage. (Absorption)
Current is determined by the battery.
 
Yes, but for the benefit of uninformed readers, the battery is not self requlating. It will take a lot of Amps if you raise the voltage of the power supply or charger up to the limit of the charger..
Yup
Batteries will try to take whatever is available.
Right up until the meltdown. lol
 
I disagree. Bulk is everything the controller can give until it hits the absorption setting i.e. 14.8 volts, after which constant voltage is held, allowing the battery to top off. Once the timed or minimum current setting is met in Absorb stage the controller transitions to float, holding the voltage at 13.6 for example. Then the sun sets and batteries will settle down to 12.8 or so (fully charged resting voltage)
I've never seen a regulating device that doesn't have a bulk setting. The bulk setting limits the voltage that the current will be delivered at. If you look at any battery manufacturer's literature, they will specify what voltage to set your bulk value to and that is what it will charge at until the absorption stage is reached.
 
I've never seen a regulating device that doesn't have a bulk setting. The bulk setting limits the voltage that the current will be delivered at. If you look at any battery manufacturer's literature, they will specify what voltage to set your bulk value to and that is what it will charge at until the absorption stage is reached.
Well then you either haven't seen very many controllers or need to look at the the instructions again.
Reread my post again.
When the sun comes up in the morning the battery is at a particular voltage. As the charger (bulk charging) begins charging the voltage will rise, as shown on the controller. Once the battery gets to the ABSORB voltage setpoint the controller will transition into Absorb mode and hold the voltage there while the current tapers off.
Granted some controllers may give you the option to put in a BULK setting. it really is meaningless because it isn't holding the voltage at that setting. The voltage it is charging at is slightly higher than actual battery voltage while the MPPT is converting the higher input voltage to that number and consequently maximum amperage it can create
Here's the charging options for my Midnite Classic controller. You might notice there isn't a BULK setting.
 

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Okay, I said "regulating device", I was not specifically talking about solar controllers. I haven't, until now, seen that controller. Thanks, that's interesting, but doesn't change my advice to the OP. He can still look and will likely see what I was pointing out.
Aboard my boat, I have Victron solar controllers and a older PWM controller, a Xantrex TC2 shore power charger that replaced an older one of a different brand, and a Balmar regulator for my alternator. All have bulk, absorb, and float settings which are set to Trojan's specifications for each stage.
So what was your advice to the OP, or were you just browsing the thread looking for an opportunity to take it off the rails? lol
 
Keep on topic or receive warning points and suffer posting restrictions
Okay, I said "regulating device", I was not specifically talking about solar controllers. I haven't, until now, seen that controller. Thanks, that's interesting, but doesn't change my advice to the OP. He can still look and will likely see what I was pointing out.
Aboard my boat, I have Victron solar controllers and a older PWM controller, a Xantrex TC2 shore power charger that replaced an older one of a different brand, and a Balmar regulator for my alternator. All have bulk, absorb, and float settings which are set to Trojan's specifications for each stage.
So what was your advice to the OP, or were you just browsing the thread looking for an opportunity to take it off the rails? lol
This thread, from the beginning , is talking about settings. As far as I can tell my comments are pertaining to the topic at hand. Yours OTOH contain little swipes at my comments. You really need to be better informed when giving out advice like when you said, for example "Absorption is always lower and is going to be somewhere between 13.4 and 13.8." This sounds like you know very little about battery charging and charge settings. You really have no business giving out advice till you have a better understanding of the topic at hand.
As far as your little pot shots are concerned you seem to be the one taking the thread off the rails.
 
Keep on topic or receive warning points and suffer posting restrictions
This thread, from the beginning , is talking about settings. As far as I can tell my comments are pertaining to the topic at hand. Yours OTOH contain little swipes at my comments. You really need to be better informed when giving out advice like when you said, for example "Absorption is always lower and is going to be somewhere between 13.4 and 13.8." This sounds like you know very little about battery charging and charge settings. You really have no business giving out advice till you have a better understanding of the topic at hand.
As far as your little pot shots are concerned you seem to be the one taking the thread off the rails.
Your comments in this thread are limited to one response to me. Nothing whatsoever to the OP. Maybe you should try helping him instead of picking fights with other commenters. LOL
Little pot shots and swipes? In one response to you? Me thinks you must be a tad sensitive if you think I said anything that resembled either.
You are the one who replied to me, you are the one who got this going.
If you disagreed with what I said, that's fine, but it didn't necessitate a reply. That was your choice based on a single controller of a single type. You seem to have a vast amount of knowledge of that controller, good for you. I made clear in my comment to the OP "regulating devices", not specifically solar controllers. I listed several types in response to you, that are on my boat, that prove my point.
One last thing is that I was talking to the OP, not you. Maybe you should learn to use your scroll button? You seem to be more addicted to arguing in online forums than you are to solar. (That was a pot shot)
 
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