New Battery Charging Behaviour

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Caved in and finally bought a replacement (GS 46B24L (NS60L) 45Ah/20hrs) GF (doing the Taiwanese talking) said the "black hand" was just putting "liquid" in it when I arrived, which, if true, suggested it should be shiny and new.

My understanding is/was they were effectively almost fully charged at that point, but when I got it home I thought I'd give it a top-up.

Didn't, unfortunately, put a voltmeter on it before I started.

Charger (3 stage "smart" charger, allegedly) has three output settings "moped" (about 2 amps indicated usually) "motorcycle" (about 4-5 amps indicated usually) and "car" (about 6 amps indicated usually).

When I hooked it up on the "car" setting it was showing 8 amps, the highest I can remember seeing it do, suggesting the battery was pretty low.

Had to go out in a hurry and didn't want to leave it that high, and put it on the lower setting (instead of the lowest setting, which would perhaps have been better)

Now I'm back (11 hours later) and its still showing 5 amps. Turned it down.

So a couple of questions

Is this normal for a freshly flooded battery, which this was supposed to be?

Whats the optimal charging regime for a new battery? As low current as possible or trust the chargers alleged smarts and set it to "car"?
 
A "dry charged" battery will not be fully charged after putting the acid in. In the auto business it is common to just install it and allow the vehicle's charging system to charge it through ordinary use. The dry charge will have enough energy to start the car initially.

With big expensive batteries or people who are prone to over-think things, electrical charging at a slow rate (0.05 of the AH rating) for several hours should be done before placing in service.

http://support.rollsbattery.com/support/...eries-detailed-

The most important thing about battery replacement is to be sure the car's charging system is working properly.
 
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You should also see what your battery charger does on a known-good battery by testing the battery voltage while charging. It sounds like it is not automatic.
 
2 amp setting overnight is my general procedure. I have a couple cheap .5A smart chargers that I use every month to top off the batteries in my fleet.
 
Something is strange here if you've had the charger on 11 hours and it is stall at 5 Ampers. I would have expect the charge rate to have tapered to ~ 1 amp. Ed
 
Sounds about right, keep an eye on it, it should lower amps soon. Batteries are rarely fully charged even if already filled flooded ones. When I bring a new battery home and put it on my smart charger they vary anywhere from 60-80% state of charge based on voltage... Sometimes the newer they are the closer they are to full, but I don't measure specific gravity which is the real test.
 
I would not trust the ammeter which showed that 45Ah battery still accepting 5 amps after 9 hours.

Reading just voltage alone is pretty misleading, although most seem to think it is like a fuel level gauge.

One of these wire inline on a sub 25 amp charging source is extremely enlightening.

514lr5mczNL._SL1000_.jpg


There are dozens of different clones of this RC wattmeter from 10 to 50$us. They are pretty accurate to about eh 0.35 amp range, under which they will read a bit low, but not all of them. Luck of the draw.

Stop guessing at what a charger is trying to do, or where a battery is at, or thinking that battery voltage is a like a fuel gauge.
 
Been on the lowest (showing 2 amps) setting overnight, just turned it up to mid, (where its still showing about 5 amps but wobbling a bit).

So by my reckoning its had about an indicated 70Ah at this point.

Perhaps having it on the lower settings is keeping it charging at a higher rate, because the algorithm cuts the charging rate based on it lowering to a % of assumed capacity. If I "tell it" its a smaller battery, it'll either never tail off to the magic number, or it'll get there later.
 
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Originally Posted By: mk378
A "dry charged" battery will not be fully charged after putting the acid in. In the auto business it is common to just install it and allow the vehicle's charging system to charge it through ordinary use. The dry charge will have enough energy to start the car initially.

With big expensive batteries or people who are prone to over-think things, electrical charging at a slow rate (0.05 of the AH rating) for several hours should be done before placing in service.

http://support.rollsbattery.com/support/...eries-detailed-

The most important thing about battery replacement is to be sure the car's charging system is working properly.



Thanks

Didn't like this bit much (and not just because its got Fahrenheit in it):-

"The electrolyte temperature will rise dramatically during activation. Do not place on charge until the temperature drops below 115° F. Activation may take several days."

This makes sense if a chemical reaction follows the addition of acid to the cells.

I put it on charge about 20 minutes after purchase and it'd allegedly just been activated at that time. I didn't measure the temperature.

Duh.
 
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l.5 hrs after the above (on the middle "motorcycle " setting at an indicated 5 amps, the "charged" light was on. so it took about 75Ah before going on "float" charge.

Prior to putting it in the car, I turned it back on at the full "car" setting.

Time Indicated Current(amps) Volts (DVM on battery terminals)
09.10 6.5 15.10
09.20 6.5 15.20
09.30 6.0 15.32
10.20 6.0 15.31
10.44 6.0 15.29
11.30 1.0 (also when off) 13.09

Don't like using the hydrometer because there's always some acid loss/dribbling, and its very difficult to read numbers off it, but all the cells were in the green zone, though the two closest to the negative terminal were pretty close to its upper edge.

Now I don't have any headlights. Probably coincidence, unless running on a very marginal battery has subjected the lighting system to damaging voltage spikes.
 
It's definitely charged. It's not good to go over 15 volts in a normal charge. The charger, if it is automatic, should be shutting off sooner.

With battery in the car, start the engine leave everything else off and measure voltage at the battery terminals. If the charging voltage is too high, the battery will be damaged and all the light bulbs will burn out rapidly.
 
Suspect the lights is a faulty steering column switch and not battery related, though I'll look into on-car charging.

Column switches have given trouble with indicators in the past.

Fuzes all look OK and test light in the live fuze sockets didn't find any that turned off with the headlamp switch (I don't know which fuze is the headlamp circuit).

I'll try contact cleaner on it.
 
Whenever a light on a car doesn't light up, always check the bulb first. Always.
 
Originally Posted By: mk378
Whenever a light on a car doesn't light up, always check the bulb first. Always.


Unless it's the check engine bulb, then you just be happy it's off!
 
Originally Posted By: mk378
Whenever a light on a car doesn't light up, always check the bulb first. Always.


Well, switch being a single point of failure, worst case, and the history all made it seem likely.

I'd taken the switch cowl off last night. This morning couldn't find the contact cleaner but put a test light on the headlight fuze sockets again and it'd "spontaneously" recovered.

I suppose the switch disturbance might have improved contact.It'll probably fail again but I got it through the 6-monthly inspection while it was working.

Voltage at idle with accessory load off:-

This morning 13.83

After return from test centre and standing for a couple of hours 14.56, 14.62 (short run in between)
 
The switch doesn't have anything to do with the fuse box.

Pull the fuses and look for evidence of overheating (melted plastic, discolored metal) at the contact springs. If the springs have overheated, they lose their spring tension and will never make proper contact again --- the only cure is to replace the fuse box.
 
Originally Posted By: mk378
The switch doesn't have anything to do with the fuse box.


Uh? Doesn't the switch complete, (or perhaps cause to be completed via a relay) the circuit which the fuses are in?

Before the test light didn't show anything at the fuse sockets when the switch was on, and the headlights didn't work.

Now the test light glows on both sockets (brightly on one, very dull on the other, I'd guess upstream and downstream of the headlight repectively) when the switch is on, and the headlights work.

This seems consistent with an intermittent switch failure.

Originally Posted By: mk378
Pull the fuses and look for evidence of overheating (melted plastic, discolored metal) at the contact springs. If the springs have overheated, they lose their spring tension and will never make proper contact again --- the only cure is to replace the fuse box.


Fuses and fuse box look OK.
 
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Originally Posted By: andyd
If one is bright and one dim. Improve the ground on the dim bulb.


By "socket" I meant the two sockets that accept the two blades of the fuse.

By "test light" I meant "test light"

On third thought, I'll revert to my original thought on why the dim fuse socket is glowing at all.

My original thought was "That's odd, don't understand that".

It seems to suggest there's a bit of current leakage across the fuse holder.
 
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