External battery charger

Even if 16.4 volts might be safe for electronics still attached to the battery, I don't want some charger blasting past 14.5 volts and putting out its maximum power until the battery gets to 16.4v Like My Schumacher does, Sometimes, whenever it decides to, randomly.

Not on any battery I care about anyway.

Other times it flashes the green light and gives up when the battery still requires 5 amps to be held at 13.2v.

A single battery accepting 5 amps at 13.2v is anything but fully charged.

But the 'just fine, green light brigade' only need to see a green light, to declare it is just fine and to 'follow me over the cliff!'

Shame when they give advice.
Bigger shame when others take it.

What did WE do in the 50's the 60's the 70's the eighties and nineties when we had to charge batteries? Remember this is about CHARGERS not converters. Think a few hundred thousand campers RUINED their batteries every camping trip. Or ran back to a physiciatrist because the camping trip was "ruined" because batteries needed to be charged manually? Charger! Read the title of the thread if you will. Not converter. Oranges and road apples. We seniors could spin a timer dial on a charger while youngers are incapable of vizualizing the concept? We got along just fine without a Pakistani programmed Chinese IC tring to think for us. Fifty years ago when I shut off the charger the battery was 100% full, not 83% full or 69% full. You start percentling battery bank capacity and suddenly you find you are hauling around 80 pounds of dead weight with a bigger bank. Again in hopes of making a seeming fuzzy subject clear a battery charger is NOT a converter. But answer me this point What is the difference between a smart battery charger and a smart converter when boondocking? While people play pinchy-giggle and pin the wanger on the donkey with smart chargers to get them to do anything, I twist a dial and walk off.

RJsfishin wrote:
How many times have we heard of some hi voltage from an automotive charger killing any of our electronics, except maybe some cheap led lite that should never have been bought in the 1st place.
I also have a Schumacher charger that goes over 16 volts on most any battery I stick it on. But it has not caused any problem. Why ? Probably because it is an automotive charger made for vehicles whose electronics that can handle some 16+ volts now and then,....maybe forever. If they were to fry electronics, don't you think there would have been a recall on them ? DUH!!
I will add that I have had 2 cheap defective solar controllers pump out 17+ volts for who knows how long before I noticed it. And it hasn't hurt any control boards, or anything else that I know of.

The answer to the OP question (read his lips) is keep doing what you are doing !! Automotive smart chargers mommies didn't raise no dummies !

I have been in the automotive industry for over 40 years specializing
In electrical/electronics. I have seen high voltage (18 plus) with no harm to other systems. Here is a clip of a RV Domestic frig diagnostics manuel.

The Dometic control system will only tolerate up to 6 AC volts on the DC line. AC ripple can be measured by a digital voltmeter set on the AC scale at the main DC terminal block connections at the refer. Six volts AC or less is acceptable. If AC volts exceed 6 on the DC incoming line the power source should be cleaned up. AC voltage in excess of 6 volts will affect the processor and create erratic operation. When testing for AC ripple on the DC line put a load on the converter. The operational range of the unit is a minimum of 9.6V DC to a maximum of 22V DC. The unit will automatically shut down until voltage has decreased to 18V DC. The refrigerator requires at least 9.6V DC for proper operation; however the panel lights will continue to illuminate until voltage has dropped to 4V DC or below.

Just sayin..............

To the OP, no it will not hurt anything as long as the "never exceed voltage" mentioned above is observed. The charge profiles from the automotive charger and the converter will most likely be different so one charger will fool the other but it will not hurt a thing.

MEXICOWANDERER wrote:
Smart "chargers" are designed to be SOLD to dummies, and others who refuse to do what had been done for the last 100 years with lead acid batteries. PT Barnum put it best.

I respectfully take exception to this statement. I do not consider myself a dummy and apparently my employer doesn't either because they pay me a lot of money to take care of a lot of electronic equipment. I respect your knowledge and experience and have learned a lot from you. Just because I chose to use a smart charger does not reflect on my level of intelligence at all. It is a decision based on available time to tend to my batteries and time to work and camp and enjoy life. It is a compromise. There is a vast number of "uninformed" RV owners out there that benefit from the features of a smart charger but that doesn't make them dummys. They have jobs, wives, children and an occasional weekend to go camping. They do not have time to charge their batteries with an adjustable power supply with SG meter in hand. So what if their batteries only last 3-4 years instead of 6-8? They won't be laying on their death bed thinking "I wish I'd taken better care of my batteries". Hopefully they'll be remembering the camping trips they enjoyed.

MEXICOWANDERER wrote:
been done for the last 100 years with lead acid batteries.

take for granted? abuse? use?

Norcold says 15.4v upper limit. Can you afford to repair your fridge?

OTOH if your Norcold still works despite being on when the battery voltage was 16v or so, then let's look at the Battery to Fridge wiring for voltage drop. Maybe you can have 16v at the batts while the fridge only sees 15.3v, and that's why nothing bad happened in your case, no idea.

One person, one charger makes for an opinion.

Hundreds of people, with their chargers and electronics makes for a valid study.

When an OEM says DO NOT EXCEED XX VOLTS input, they mean it. Gyro Gearloose Fiddling in 60F temperatures is one heck of a long way from 100F or 110F temperatures.

Smart "chargers" are designed to be SOLD to dummies, and others who refuse to do what had been done for the last 100 years with lead acid batteries. PT Barnum put it best.

How many times have we heard of some hi voltage from an automotive charger killing any of our electronics, except maybe some cheap led lite that should never have been bought in the 1st place.
I also have a Schumacher charger that goes over 16 volts on most any battery I stick it on. But it has not caused any problem. Why ? Probably because it is an automotive charger made for vehicles whose electronics that can handle some 16+ volts now and then,....maybe forever. If they were to fry electronics, don't you think there would have been a recall on them ? DUH!!
I will add that I have had 2 cheap defective solar controllers pump out 17+ volts for who knows how long before I noticed it. And it hasn't hurt any control boards, or anything else that I know of.

The answer to the OP question (read his lips) is keep doing what you are doing !! Automotive smart chargers mommies didn't raise no dummies !

The lowest voltage my Ford alternator has ever put out is 12.9 volts in scorching triple digit Idaho summer weather - but this was very rare and did not last long.

My AGM batteries can stay in full charge condition going down the road during year after year of driving with around 13.6 volts or higher maintained on them, which is where the alternator's minimum falls the bulk of the time in normal warm weather. "All over the map" Ford alternator output voltage refers to what can be seen over years and years of use in a huge variety of outside temperature conditions no matter how long the conditions may have lasted.

When my AGM batteries are fully charged, the ammeter - with it's shunt in their negative main cable - shows zero amps going in-to or out-of the batteries, regardless of what the alternator ... or any other charger ... is trying to do to them.

Ya gotta love that hard current flow stop that AGM batteries come up against when they're fully charged .... that's way better than that mushy maybe-I've-arrived and maybe-I've-not-arrived current flow that continues into wet batteries when they're supposedly fully charged even when/as indicated by specific gravity readings.

I prefer K.I.S.S. over all else.

My response is to illustrate

TAKE NOTHING FOR GRANTED

AGM batteries do not require "all over the map" voltage profiles. If you start your trip with filly charged batteries then check them after several hours on the road and find them at 14 4 volts?

13.2 volts?

13.6 volts?

13.9 volts?

This is not an admonishment. This resonse has a purpose if anyone cares to learn what it is...