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:
IotaDLS30Chart.jpg 236.6K 23 downloads
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):
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.
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.
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.
Edited by Old Crow, 13 May 2022 - 01:08 PM.