Iota DLS-30/IQ4 charging graph

[Old Crow]

A recent thread about shorepower charging reminded me that several years ago I found and saved an interesting graphic representation of how an Iota DLS30/IQ4 works. (For newer WTW members, the DLS30/IQ4 is the AC-to-DC battery charger FWC has put in campers for quite a few years).

Click to enlarge:



This morning I tracked down the source. It's buried in this thread in the Northern Arizona Wind And Sun Solar forum. Specifically, it's the 'graphic' jpeg at the bottom of post #5.

That same post #5 recommends another thread and that one includes this helpful info (I edited it very lightly for readability):

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Bulk mode:
Begins with the full rated current (ampere) output of the charger. As the battery charges, the actual current delivered or accepted by the battery will decline and the voltage will increase. This is not an engineered function, it is a normal function of any battery being charged by any charger. When either the voltage hits 14.6 “High Trigger Point” or 225 minutes (3.75 hours) have passed, the charger will continue charging for an additional 15 minutes and then go into the absorption mode.

Absorption
This mode is a fully timed function for 8 hours or 480 minutes. The controller will regulate voltage to no more than 14.2 volts and the current delivered will decline as the battery charges. In a simple unregulated charger, voltage can exceed safe limits not only for the battery but for other electronic devices associated with the system. (Control circuits within refrigerators and furnaces). There are no trigger voltages functioning in this mode. It's 14.2 volts for 8 hours, period.

Float
This is a constant voltage charging mode. It's 13.6 volts for 7 days or if the battery voltage drops below a “Low Trigger Point” of 12.8 volts. During the float stage, the charger is delivering 13.6 volts with up to the rated current output of the charger. Should the voltage drop below 12.8 volts either from normal discharge or a short term heavy discharge, the IQ4 will start the charging cycle all over with the bulk charging stage

Note: There is one additional mode mentioned in the IQ4 manual called Equalization. This mode can not be initiated manually but is rather a function of time. If the battery remains in the float stage for seven days the IQ4 will start what they call an equalization charge. This is nothing more than restarting the Bulk mode charging cycle. When seven days have passed or the “Trigger voltage” drops below 12.8 volts an equalization - bulk charge is started followed by the absorption and float stage. The maximum voltage for either the bulk or equalization mode is 14.8 volts. The equalization charge is merely starting a complete charge cycle with the only difference being that it is initiated by a timed function rather than a trigger voltage. There is no real Equalization mode. Most batteries require 15 to 16 volts to equalization.

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[Old Crow]

More on DLS30 and DLS30/IQ4 units....

If you're into reading the threads I mention in post 1, keep in mind that the DLS30 has a 'dual-voltage jack'. This was originally provided to allow the owner to manually choose to charge at 13.6 volts (float) or 14.2 volts (quick-charge), depending on whether the dual-voltage plug is in the jack or not.

Iota developed the IQ4 Smart Charger to turn the DLS30 into an automatic three-stage charger. It was originally a separately-purchased 'pendant' which plugged into the dual-voltage jack on the DLS30 to give it 3-stage charging (i.e., bulk, absorption, and float).

Later, Iota began manufacturing the "DLS30/IQ4" model which put the IQ4's logic on a board inside the unit. The DLS30/IQ4 is just an additional model, it does not replace the DLS30. Iota has market segments where the DLS30 is used as a power supply and the IQ4 isn't needed for that.

Iota not only kept the IQ4 pendant, they went on to develop 9 variants of smart-controller pendants for the various chargers they sell. Unfortunately, the ones for the DLS30 don't work with the DLS30/IQ4 as those don't have the dual-voltage jack.

 

[HappyCampers]

Helpful and appreciated Old Crow! I haven't followed up on the on old threads yet, but plan to.

I had not been using shore power at home to recharge or tend the battery previously and we never use it on the road. Thanks to threads like this and contributions by other members, I have put much more informed thought into battery maintenance. I am hoping this helps sustain our new AGM battery for many years.

My current understanding is that the AGM-specific pendant (dongle) optimizes charging or reduce the chances of damage (non-IQ4 DLS30)? It's a nominal cost and would allow us to plug in here at home and just forget about it for weeks or months at a time. I'm just a bit surprised this is necessary since the camper was originally outfitted with an AGM battery and no dongle???

 

[Old Crow]

Unfortunately, we don't know the answer to one of the critical questions: Do Iota's AGM-specific and LIFEPO-specific pendants do a significantly better job than the internal IQ4 in an application like ours? Or are the differences so minor that they're really just addressing a marketing issue rather than a technical one?
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[pvstoy]

Old Crow thanks for posting a summary as a good reminder how it works and what to expect aiding in service diagnosis!

 

[craig333]

I think the differences are pretty minor. For most of us who only use the Iota for charging occasionally I really don't think it makes much difference.

 

[Stray Dog]

Old Crow, thank you for posting. I've taken this info, printed it and included it with my instructions and manuels packet in the camper. These questions seem to come up frequently and you've provided some good answers...

 

[rubberlegs]

We use shore power quite a bit, to top off the battery every month and to charge the battery and cool the fridge the morning of a trip.

I wrote to Iota and got information on the internal DLS30/IQ4. They sent a PDF of their manual "IQ4 Charge Controller for DLS". It backs up the information in the first post above (Thanks, Old Crow -- wish I'd seen this a week ago!).

It seems to be ideally suited for a flooded lead acid battery like our truck has, not the AGM that Four Wheel Camper put in our camper. Maybe in 2018 Iota didn't have the AGM dongle? There is a difference if you keep the shore power plugged in all the time. It appears to be designed exactly for that purpose since it monitors time up to a week or more.

I was satisfied that the Iota charger wouldn't cook my brand-spanking new lithium battery that I had just discharged to 0%, per the manufacturer's instructions. Since the voltage was low, I charged it with solar and lithium-specific charger (Renogy DCC30S) to about 10%-ish (the Batt Mgmt Syst needs two cycles to get accurate percentages), which went slow due to our lack of sun. Then I wired the new batter in the camper and started the charger. The battery voltage was above the "low trigger" of 12.8, so the charger seemed to go into float stage, although it may have been in absorption phase. Wish I could remember the voltages.

At first the Iota was putting out 5-7 amps or so, and this was gonna take a while. I left it plugged in for 18 hours, and the amps dropped to the 3 range by the end. The battery got to about 70%. This is pretty darn slow! But it got sunny and I was able to charge up the battery to 100% using solar panels and the MPPT charger.

I think the Iota will be ok for our lithium battery, plugging in overnight before a trip, then the first hour of driving should finish it off.

Maybe I'm hijacking this thread!

 

[Jon R]

If I turn on my 2021 Iota with my lithium battery at a fairly high charge level, the charger starts in bulk mode and ramps the charger output voltage up until it gets to 14.8 volts trying to hit 30 amps. It does not stop at 14.6. I’ve measured it. Not a huge deal if you are monitoring it, but higher voltage than I want to apply.

 

[pawleyk]

I think the differences are pretty minor. For most of us who only use the Iota for charging occasionally I really don't think it makes much difference.

100% correct. It really makes very little difference for most of us, who are charging primarily via solar and from the truck.

 

[rubberlegs]

SoC Voltage Amps time Elaspsed time
0% 12.25 27.21 09:16 AM
0% 12.41 24.84 09:17 AM 00:01:00
11% 13.19 8.74 10:16 AM 01:00:00
31% 13.38 4.86 01:23 PM 04:07:00
41% 13.39 4.58 03:39 PM 06:23:00
61% 13.44 3.46 08:14 PM 10:58:00

61% 13.35 4.84 09:26 AM 10:58:00
66% 13.48 2.03 11:25 AM 12:57:00
67% 13.48 2 11:59 AM 13:31:00
68% 13.49 1.9 12:31 PM 14:03:00
70% 13.49 1.84 01:31 PM 15:03:00
72% 13.49 1.81 02:22 PM 15:54:00
76% 13.5 1.78 04:32:00 PM 18:04:00
78% 13.5 1.71 06:10:00 PM 19:42:00
80% 13.5 1.63 07:10:00 PM 20:42:00
82% 13.5 1.63 08:16:00 PM 21:48:00
85% 13.51 1.52 10:12:00 PM 23:44:00

85% 13.48 2.31 09:47:00 AM 23:44:00
87% 13.51 1.44 10:32:00 AM 24:29:00
87% 13.51 1.36 10:59:00 AM 24:56:00
88% 13.52 1.27 11:59:00 AM 25:56:00
90% 13.52 1.22 12:59:00 PM 26:56:00
91% 13.52 1.3 01:50:00 PM 27:47:00
92% 13.53 1.22 02:59:00 PM 28:56:00
94% 13.53 1.22 03:59:00 PM 29:56:00
95% 13.54 1.19 04:59:00 PM 30:56:00
96% 13.54 1.17 05:59:00 PM 31:56:00
97% 13.54 1.15 06:59:00 PM 32:56:00
98% 13.54 1.07 07:59:00 PM 33:56:00
99% 13.54 1.06 09:00:00 PM 34:57:00
100% 13.55 0.98 10:00:00 PM 35:57:00
100% 13.56 0.85 11:48:00 PM 37:45:00


Here's how our DLS-30/IQ4* charged our new SOK 100Ah lithium battery. This was the second 0-100% charge that our SOK battery instructions called for, to calibrate the battery management system. Perhaps it would have charged even higher, but I gave up at almost 38 hours and "100%". I should have gone further with our solar LiFePO4 charger, but it wasn't hooked up for a few more weeks.

I suppose why I've been told it will only charge a LiFePO4 battery to around 80% is because it takes too long to continue. But plugging in overnight before a trip will get us pretty high, and driving an hour will get us topped off.

* designed for lead acid batteries

 

[Jon R]

Looks to me like the charger was in power supply mode.

 

[Vic Harder]

How are you verifying SOC %?

 

[rubberlegs]

SOC% was from the battery's BMS.

 

[Old Crow]

It would be interesting to see what the DLS30/IQ4's LED (on the fan end of the unit) does during a charge of a LiFePO4 battery. I assume that's not easy to see (given where the DLS is mounted). But I just don't know if that's the case. Is it possible to see the LED or its reflection?

The manual (here) says this:

"THE IQ4 LED INDICATOR (ONLY ON DLS MODELS WITH INTERNAL IQ4) DLS models with an internal IQ4 smart-charger give the user the benefit of automatic Bulk, Absorption, and Float stage charging. This increases the charging capacity of the DLS charger, decreases charge times and insures proper and safe battery charging without over-charging. The green LED on the fan-end of the DLS will indicate which charging phase the DLS unit is currently in. When the unit is first activated, the LED will flash as it reads the number of the cells in the battery. The unit will then proceed directly to the Bulk charging or Float charging phase depending on the charge status of the battery. Use the LED CODE TABLE for reference when checking the LED."

The LED code table shows the LED should flash six times when plugged in, then go into a rapid-flashing green (Bulk). When it goes into Absorption, the LED will slow-flash green. And when it goes into Float the LED will be solid-green.

(Note: The table also shows voltages as Bulk=14.8, Absorption=14.2, Float=13.6 when you multiply them out)

After reading through the text description of how the charger works (in post 1), my first thought was the LED would, in a long charging session, proceed through all three modes. Bulk mode would normally be waiting for battery voltage to rise to 14.8 but if it doesn't do that within 225 minutes, it would go ahead and switch to Absorption mode. And Absorption mode simply runs for 480 minutes before switching to Float.

The other thought that occurs to me is I wonder if results vary by battery manufacturer. LiFePO4 battery chemistry is (I assume) the same but Battery Management Systems may be programmed differently by the different battery manufacturers.


Edited 2/2/23 to add:

Newer DLS30/IQ4 units may have LEDs with multiple colors. According to this December 2021 announcement the colors are solid green=Bulk, flashing red=Absorption, amber=Float. When not powered, the newer LED appears to be translucent white while the older LED model appears to be green.