Boondocker converter setting

Battery care and feeding is significantly different between connected to public power versus short term off-grid and long term off grid.

Set it to the bulk/absorption voltage, and check the water level in the battery at least once a month. Preferably, the charger could go to absorption for an hour or two when charging, then drop down to float voltage. But if your's can't do that, absorption voltage or a bit lower is correct.

But it depends on how often you use it, and how often you charge it. For daily use, set it to absorption voltage. If it sits charging for days/weeks between use, set it closer to float voltage. You can't really overcharge, instead you end up needing to add water more often.

Equalization is not the common case, so don't worry about it. And, it's not so necessary for an RV. A large part of the reason is to move the electrolyte around to eliminate stratification - and that happens naturally when bouncing down the road. The other reason is to balance the cells, and that only needs to be done infrequently, maybe spring and fall on an RV.

Equalization voltage is specified at 15.9. I’m pretty mild in my usage so far of the batteries, never seen it dip below 75% of charge while dry camping. This is the first extended camping trip where we’ve had shore power, so just want to make sure I don’t muck anything up with new batteries. Will do the hydrometer testing when we get back home.

Set it for the specified "charging voltage" (14.8 common) and leave it there till the batteries are as full as you are going for (90% when off grid on generator eg, or 100% if at home on shore power)

How do you know when they are at 90 or 100? Now you need an ammeter to see when amps have dropped to your target amps. Or get the SG up close and check the SG again next day to see if the "SG Lag" has caught up.

14.8 is for 25C, so if it is cold out, set the voltage higher. 15.2v at 5C is equivalent to 14.8v at 25C. If it is hotter out set it a tad lower, 14.6. There are tables for that.

I doubt your batts will equalize at only 15v when most require 16v.

Number will be different if you are using it just for battery recharging (minimum availability of 120 VAC (in which case bulk rate voltage is correct-- probably around 14.2 VDC)

OR

If you will have 120 VAC all the time (in which case you will want float rate voltage-- probably around 13.2 VDC)

Basically the batteries call the shots, not the charger. Read the Rolls & Surrette user manual. Study it.

A real battery like a Rolls reacts differently to different lifestyles. The milder and less frequent the discharges the less aggressive you must be about charging.

Do you have a Francis Freas hydrometer? It is a must so you can measure accurately the state of charge of the battery. You do not need to use it every time you charge. You need it to find the correct settings for the boondocker. There is no alternative to this. Any other way is guesswork.

Set the charger to 14.8 volts.

Let the boondocker do it's thing

If the battery cells are bubbling too vigorously at the end of the charge the voltage setting is too high. Back it down to 14.4 the next charge. Light bubbling at the end of the Bulk + absorbsion cycles indicates full charge. Test one cell. Is it indicating full charge.

Back the voltage setting down a tenth of a volt at a time until the light bubbling minimizes but the batteries indicate full charge. Whatever it takes. No smart charger on the face of the earth can do what you are doing.

If the batteries bubble lightly but the hydrometer indicates say 1.265 volts, back the voltage down .2 volt but INcrease the length of time spent charging my 20 minutes.

Does the hydrometer agree that the batteries are fully charged?

You need to test a single cell for this.

When you find the formula you are finished with the hydrometer for a long while. Put it away.

Then enjoy a good converter and a superb battery. When people are fumbling buying another set of "the low-priced-spread" batteries, you will be relaxing... :)