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12VDC, 30A Smart Battery Charger for $40.

Float is fine as long as it at or below the full resting voltage of the battery.
Think of it as load assist.
Yes, that is an important distinction and one that may make some Lead Acid chargers not suitable for Lithium unless they can be adjusted to to Float below the CV voltage.
 
The way a charger lowers the amps it delivers is by reducing the charge voltage.
Its the differential between the battery voltage and charger voltage that determines the current flow.
Yes, we have had this conversation before and it is useful for readers to see two explanations of the same concept. I use the term "tapers the Amps" to describe the measured result but you are correct that the charger does this by lowering the voltage. We don't see the voltage that the charger is actually putting out because when it is connected to a load like a battery we only see the voltage of both at their common interface.
 
I would use the correct module for your batteries.
You are right: attempting to charge at the float voltage of 13.6V (without the IQ4 module) is just too slow for the bulk charge. I ended-up ordering the IQ4LiFePO module as well.
 
I received the IQ4LiFePO module and I am not happy about how it works. The cycle it performs is that it proceeds at CC at 30A (with a max. voltage of 14.7V) and then switches to a float at 13.6 V once 13.6 V is reached or 120 min have passed whichever comes first. Since I have a 200 Ah pack, this means it added 60 Ah to the pack and then went to float at 13.6, this made the rest of the charging process EXTREMELY SLOW. This 2 hour limit is completely stupid and I cannot recommend this charger to anyone.
 
I cannot recommend this charger to anyone.
Did the description not give those details? If someone wants that functionality, would you recommend it or are there other things wrong with it?
That is one thing I like about plain power supplies, they are dumb CC/CV devices. I like that my inverter can Float my pack at a a voltage I select for a period I can also select.
 
I’m a little confused by what I see in the lithium module doc but a quick test when I get everything will be all I need to characterize it and figure out if it’s only suitable for my LAs.
Would you recommend the LIFEPO4 IQ Module for this charger and 12VLIFEPO4? I'm in the market for a good RV charger/converter and this seems to fit the cost bill.
I'm skeptical based on the IQ-LIFEPO documentation, but stay tuned.
I received the IQ4LiFePO module and I am not happy about how it works. The cycle it performs is that it proceeds at CC at 30A (with a max. voltage of 14.7V) and then switches to a float at 13.6 V once 13.6 V is reached or 120 min have passed whichever comes first. Since I have a 200 Ah pack, this means it added 60 Ah to the pack and then went to float at 13.6, this made the rest of the charging process EXTREMELY SLOW. This 2 hour limit is completely stupid and I cannot recommend this charger to anyone.

Did the description not give those details? If someone wants that functionality, would you recommend it or are there other things wrong with it?
Yeah that's exactly what the doc says it does which is why I was skeptical. Carlos beat me to the test. It's not great, but it fits my use case where I want to have my LFP standby systems holding at less that 100% but be able to charge them up in 2 hours or less in advance of a potential power outage storm event (thunderstorms, microbursts, macrobursts etc.)

I agree that it's not a good general purpose charger for LFP, but some people with smaller battery banks might find it useful at the discounted price. Since I have both LFP and AGMs it's actually a pretty good deal for me. Most people should probably look elsewhere.
 
Update:

1) what the IQ4 kit does is it sets the max V to 14.7V for ~2 hours (max. I is always 30A) and then drops it to 13.6V. There is some extra intelligence to check periodically if the voltage drops, etc. (so you can fool it by disconnecting from the battery for a while and then it will kick in the 14.7V again)

2) An alternative is to simply put the "plug" that comes with the PSU (mine did not have one but it is easy to make: just use a headset cord and wire cables 1+3 together). This makes the max V to be 14.2V permanently (but max I still 30A, of course) which is 3.55V per cell and may be perfectly fine.

So not all is lost, having paid only ~$30 for the psu and ~$20 for the IQ module this is still not bad. But I really think they should not have put the time limit, it makes no sense for LiFePO4. Maybe some day I will open the module and see if I can mod it.

For the moment I still don't have a BMS so I need to be extra careful with the cells. Once I have the BMS I may be able to push the PSU limits more.
 
Update:

1) what the IQ4 kit does is it sets the max V to 14.7V for ~2 hours (max. I is always 30A) and then drops it to 13.6V. There is some extra intelligence to check periodically if the voltage drops, etc. (so you can fool it by disconnecting from the battery for a while and then it will kick in the 14.7V again)

2) An alternative is to simply put the "plug" that comes with the PSU (mine did not have one but it is easy to make: just use a headset cord and wire cables 1+3 together). This makes the max V to be 14.2V permanently (but max I still 30A, of course) which is 3.55V per cell and may be perfectly fine.

So not all is lost, having paid only ~$30 for the psu and ~$20 for the IQ module this is still not bad. But I really think they should not have put the time limit, it makes no sense for LiFePO4. Maybe some day I will open the module and see if I can mod it.

For the moment I still don't have a BMS so I need to be extra careful with the cells. Once I have the BMS I may be able to push the PSU limits more.

I've been back and forth with Iota expressing some frustration on this very issue.

They finally indicated we should be able adjust the pot in the unit to the voltage we need. I will attempt that without the LIFEPO module to see if I can set this as close to 14.5/14.6 as I can
 
I've been back and forth with Iota expressing some frustration on this very issue.

They finally indicated we should be able adjust the pot in the unit to the voltage we need. I will attempt that without the LIFEPO module to see if I can set this as close to 14.5/14.6 as I can

Do you mean the pot inside the main unit? Have they mentioned a way to remove the 120 min time limit of the IQ4? That is what I'd really like. This may have been setup in the firmware of a microcontroller inside the IQ device, so probably can't be changed. But if you are in touch with them that would be nice to ask.
 
Do you mean the pot inside the main unit? Have they mentioned a way to remove the 120 min time limit of the IQ4? That is what I'd really like. This may have been setup in the firmware of a microcontroller inside the IQ device, so probably can't be changed. But if you are in touch with them that would be nice to ask.
I asked more than once. They indicated there was no way to user change it. I'm sure there is but its software. I was pretty clear that it completely hamstrings the product -- especially with the size of batteries today -- It basically limits the DLS-30 to a 60AH battery bank.

The POT inside the unit, i'm told, can set the voltage to the user recommended value. This should essentially solve for my problem. The BMS will cut off at full charge regardless.

I'll let you know when I get to opening the unit.
 
I asked more than once. They indicated there was no way to user change it. I'm sure there is but its software. I was pretty clear that it completely hamstrings the product -- especially with the size of batteries today -- It basically limits the DLS-30 to a 60AH battery bank.

The POT inside the unit, i'm told, can set the voltage to the user recommended value. This should essentially solve for my problem. The BMS will cut off at full charge regardless.

I'll let you know when I get to opening the unit.

Its like these folks are hypnotised by the headlights of the oncoming lifepo4 freight train.
 
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I asked more than once. They indicated there was no way to user change it. I'm sure there is but its software. I was pretty clear that it completely hamstrings the product -- especially with the size of batteries today -- It basically limits the DLS-30 to a 60AH battery bank.

The POT inside the unit, i'm told, can set the voltage to the user recommended value. This should essentially solve for my problem. The BMS will cut off at full charge regardless.

I'll let you know when I get to opening the unit.

I did open the unit some time ago (to install an on/off switch) and noted a small pot. Also of note: if you are happy with 14.2V then shorting the 1-2 pins on the IQ connector raises the voltage from 13.6 to 14.2. Thay may actually be enough. I will experiment more once I receive my BMS.
 
@carlos1w So you not happy because of the 120min max time frame. It sounds like your battery bank is similar to mine. I have 8 LifePo batteries making 2 banks of 4 ( 12v ea). not knowing how long they will take to charge, can I assume from your work, it will take much longer to charge all 8 batteries up? My plan is to put this into the RV for charging the batteries. I wont have any type of solar at this point. these will be house batteries to run everything. then 1 or 2 days, turn on Generator to power them back up. I was hopping this would be good unit for RV.
 
@carlos1w So you not happy because of the 120min max time frame. It sounds like your battery bank is similar to mine. I have 8 LifePo batteries making 2 banks of 4 ( 12v ea). not knowing how long they will take to charge, can I assume from your work, it will take much longer to charge all 8 batteries up? My plan is to put this into the RV for charging the batteries. I wont have any type of solar at this point. these will be house batteries to run everything. then 1 or 2 days, turn on Generator to power them back up. I was hopping this would be good unit for RV.

You don't say how may Ah your cells are. The larger the Ah, the longer it's going to take to charge them. If you use an AC-DC converter with a small amp rating, it's going to take a loooong time. Size the converter up to what your electrical system can handle and what's reasonable.

I installed a 55 amp converter to charge my 560 Ah of LiFePO4 batteries. That's not a lot of charging, but I don't expect to use it that often. I'm rarely on shore power and my solar should take care of it 99% of the time. It's there mainly because I needed a converter that used a LiFePO4 charge profile, just in case someone plugged my trailer into shore power or turned on the on-board generator.
 
sorry @HRTKD .... 280Ah its the group buy from Michael.
so you point is to get a better stronger charger that will make the charge in the 2hr time limit of the LifePo controller. I wont have solar for a while... if at all.
 
sorry @HRTKD .... 280Ah its the group buy from Michael.
so you point is to get a better stronger charger that will make the charge in the 2hr time limit of the LifePo controller. I wont have solar for a while... if at all.

It depends. Do you have limited time that 120vac is available? If a generator is your main source of 120vac then the answer is yes and a 30 amp converter probably isn't going to pump enough juice into your batteries in the amount of time you want to be running your generator.

Either a higher amp rated converter in the IOTA line, or a converter from a different manufacturer.

I don't know what generator you have so I'll use mine as an example. It's an Onan 5500 watt. It's rated to produce a solid 45 amps of AC. Most converters fit well within that range. I chose the DLS-55 because it's at the top of the range that still uses a 15 amp AC circuit. To move up to a higher rated amp output converter I would need to change the circuit breaker in my main distribution panel and maybe upgrade the wiring. The generator can certainly produce enough power to support that, but what if the air conditioner is running at the same time? Or maybe you're running a space heater. You have to use a converter that fits with your system. The OEM converter that came in my trailer was a 45 amp model.
 
my time is limited with the 120v generator only by my desire to listen to it for the time it takes to charge. so NO, i can run as long or as little. I try to use it as little as possible. my generator is a Honda EU 2000i quite model. its 1600Va = 13.3a. the RV does have 30a service for shore power connection. I think primarily for the AC on top of the RV.
Ill need to check my RV and see what charger is already in there. I don't think its compatible because RV came with standard lead acids.

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Ill need to check my RV and see what charger is already in there. I don't think its compatible because RV came with standard lead acids.

Right, it probably doesn't have a compatible charge profile. But the AC input amp rating of the converter will provide you some guidance of what you need to stay within to not overload your generator.

A friend of mine has two of those generators that he runs in parallel. The converter he uses can charge his lead acid batteries at 75 amps DC.
 
I have a LiFePO4 system made in a 4s configuration of 202 Ah cells. At 30 A this would be (from 0% charge to 100%) just under 7 hours which is fine with me. But the stupid IQ4 module lowers the voltage to 13.6V after just 2 hours. This is a really dumb design flaw. It should keep CC as much as needed (by monitoring the cell voltages). I am going to simply disable the IQ4, install the plug that raises the "float" to 14.2, and adjust the internal pot to see if I can raise it. Then it will be up to the BMS to control the charging. Sigh...
 
@carlos1w how is it we can fix this... Today i found out my RV panel supplier has a replacement model for the panel RVs use... WF-8950L2-MBA. Is a plug and play version for LifePo model batteries. charge profile, i have not heard back from them. It shows as 50a output. mind you this is depend on input current and wire capability. However, my RV has a 30 connector cable, so that is my judge. Given that, my 30a input will give my 280ah batteries full charge at .... 9hr? 30ah / 280 batteries = 9hr. Is my math correct? yes there might be some loss. Have not used the RV with the new battery monitor yet so I don't know how long it will take to deplete the batteries. I might not use all the capacity in a given weened.. So could recharge when we get back home.
 
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