Battery Monitor Lights

[markopolo]

KiB monitor panel
http://www.kibenterprises.com/troubleshoot/k_panel.pdf

C: CHARGED 12.7+ volts - green light (4th light lit) = Charged or Charging Battery = OK
G: GOOD 11.9+ volts - green light (3rd light lit) = more than 11.9 volts but less than 12.7 volts = between 1% and 60% discharged = Charge it soon!
F: FAIR 11.2+ volts - green light (2nd light lit) = more than 11.2 volts but less than 11.9 volts = between 60% discharged and 95% discharged = Charge it now!
L: LOW 6.0+ volts - red light (1st light lit) = between 95% discharged and dead = look in wallet for battery money!

Remember: Two lights, too low!

http://www.windsun.com/Batteries/Batter ... 20Voltages

[markopolo]

I think it is worth bumping this topic up.

KiB made or makes a lot of the monitor panels we see in RV's. These type of panels have lights that are meant to give you an idea of the charge state of the battery.

If you have one of these panels then it is a good idea to get an idea of what voltage range is indicated by the lights. You can do this with a multimeter. You can also look up the data in product manuals.

KiB K panel 1991 and prior:
Charge 14.5V+
Good 12.6V+
Fair 12V+
Low 6V+

KiB K panel Feb 1991 to Jan 1992:
Charge 13.3V+
Good 12.6V+
Fair 12V+
Low 6V+

KiB K panel later than 1992:
Charge 12.7V+
Good 11.9V+
Fair 11.2V+
Low 6V+

KiB M panel:
Charge 12.7V+
Good 12.1V+
Fair 11.6V+
Low 6V+

On the old panels - prior to 1992 - "good" was a great voltage. On the newer panels 11.9V or 12.1V for Good is a low voltage.

The AGM's in my van will measure 12.8V at rest so they would trigger the "Charge" light when fully charged even if the charger is unplugged.

K Panel:

kib k panel.JPG

M Panel:

kib m panel.JPG

[booster]

Great post, particularly the highly volatile voltage thresholds over time. We had some early on problems with tank sensors that were panel related, so I got a chance to call them about it. I also asked about the lights, that appeared to be saying the batteries were OK, when in fact they were nearly dead and buried. They were pretty open about it, and I think very correct, in saying they are constantly chasing a moving target because of load on the systems while checking. Many of us have also learned that hard lesson . In reality, there is no way to even remotely chose thresholds that are accurate when the load can change a bunch, the battery bank size can change, the battery type (wet, agm, etc), can change, the wiring can change, etc.

Bottom line is that the lights are pretty useless unless you turn everything off for an hour or more before checking, and then the current ones still don't tell you much because of the huge range in the middle. A cheap plug in voltmeter is a much better choice, or a small wire in. Of course, the best choice is always a shunt based battery monitor, but it is much more cost and work to install.

From what we have heard lately, the lights are the only monitoring system in some of the etrek type vehicles, which as Marko's numbers show, means that the owners are really flying blind on the condition of the batteries.

[obgraham]

I agree with Booster. The idiot lights in my Etrek are worse than useless, because they almost always show 3 of 4 on, regardless. I can't quite understand why they didn't install a proper voltage meter into the complex system for which I paid a boatload of cash.

The plug-in Innova meter discussed here often was a revelation to me.

[booster]

Originally Posted by obgraham

I agree with Booster. The idiot lights in my Etrek are worse than useless, because they almost always show 3 of 4 on, regardless. I can't quite understand why they didn't install a proper voltage meter into the complex system for which I paid a boatload of cash.

The plug-in Innova meter discussed here often was a revelation to me.

Maybe that is the "proprietary" part of the system they talk about so much. Make it so folks don't know that their very expensive batteries and control system aren't working well and that the batteries will fail early. Out of sight/out of mind.

[markopolo]

Many etreks seem seem to be split 12V & 24V. Two voltage meters would be needed, one for the 12v side & one for the 24v side.

Or, add an equalizer / balancer and measure only the 12v side.

[booster]

Originally Posted by markopolo

Many etreks seem seem to be split 12V & 24V. Two voltage meters would be needed, one for the 12v side & one for the 24v side.

Or, add an equalizer / balancer and measure only the 12v side.

Very good point about the split systems needing two meters if they don't have some sort of balancer.

I have been doing a little bit of reading about balancers that are on the market, and they are often apparently very different from each other. The Victron only balances out the batteries on the recharge cycle, which would not be very good in the Roadtrek split voltage application. The Vanner does it the opposite, making sure the batteries stay balanced on as the battery bank supplies 12v power, which would make a lot more sense in the Roadtrek setup.

[NLRevell]

Basic take off is that if you don't check the cells with a Hydrometer, you really have no idea what state the batteries are in. Lights and voltmeters only give the roughest idea.

[BobB]

Originally Posted by NLRevell

Basic take off is that if you don't check the cells with a Hydrometer, you really have no idea what state the batteries are in. Lights and voltmeters only give the roughest idea.

How do you use a Hydrometer on a sealed AGM or on a Lithium?

[avanti]

A Trimetric monitor or equivalent is the best investment you can make when it comes to power awareness. Not only will you know where you battery stands, but you will come to know exactly what each power consumer in your rig is costing you in amps.

[NLRevell]

Originally Posted by BobB

How do you use a Hydrometer on a sealed AGM or on a Lithium?

Ah! That is a problem. I am an old-school knuckle dragger. My van has Lead Acid batteries. Go heavy, baby!

[BobB]

Originally Posted by NLRevell

Ah! That is a problem. I am an old-school knuckle dragger. My van has Lead Acid batteries. Go heavy, baby!

LOL

At some point I am going to switch my old Flooded for an AGM, with a new charger. In the meantime I use one of the plug-in devices.

[BobB]

So other than Trimetric, who make the best monitors. I assume they need to have a shunt in the circuit somewhere. So straightforward installation would be nice for those of us electrically challenged.

I also know they range in price. I have simple system, one battery, but SOC in addition to seeing Volts and Amps would be nice. Recommendations?

[booster]

Depending on what your budget and desires are, you can get the battery monitor tied into you new charger. Other than that, I think most chose the Trimetric. It is easy to wire in with only a few connections, and it does have a shunt. It also allows you to set the full battery recharge parameters, which some don't. It does not use Peukert, which is a minor negative. With a single battery, adding a shunt is usually easy. It can get harder with multiples in various locations.

The makers of the monitors like to talk about the SOC readout and how handy it is, which is true, but it is also not the most accurate of the readings, especially on recharge. It will also get less accurate with each cycle that doesn't get the battery totally full.

For telling how full the batteries are, we prefer to use the amp hour meter, which we find to be easier and more consistent. Others may not agree, and like the SOC, which is fine as long as they understand the accuracy parts.

Being able to see the actual charging amps, and having a monitor that uses amps as one of the "full" criteria will give you the ability to adjust your charger (if it is adjustable) to the best combination of settings to get the reliable charging. You will also be able to see how much all your "stuff" uses for power, which can be enlightening.

[avanti]

When I added my Trimetric's shunt, I fabricated a custom bus-bar out of a bit of copper tubing:



Much easier, cheaper and cleaner than a separate cable. You can find the details here:
2014 Great West Vans Legend SE - Page 8 - Sprinter-Forum

[BobB]

Markopolo

Somewhere I got this State of Battery Charge - Voltage chart, but this one gives it for various temperatures. Forget the source, but at the time I assumed it was reasonably accurate - it does have the same voltages @ 70F as the one you posted. Made sense that voltages would vary with temperature.

It is very useful checking voltages in middle of winter or summer. Can you verify (1) is it accurate (2) pretty sure I found it pertaining to Flooded. Would AGM, GEL be similar or would you need new chart? Lithiums?

[BobB]

Originally Posted by avanti

You can find the details here:
2014 Great West Vans Legend SE - Page 8 - Sprinter-Forum

avanti,

Link shows message but no photos - maybe because I am not member of sprinter forum?

Can you post photos here?

[BobB]

Originally Posted by avanti

NOTHING posted

[markopolo]

Originally Posted by BobB

Markopolo

Somewhere I got this State of Battery Charge - Voltage chart, but this one gives it for various temperatures. Forget the source, but at the time I assumed it was reasonably accurate - it does have the same voltages @ 70F as the one you posted. Made sense that voltages would vary with temperature.

It is very useful checking voltages in middle of winter or summer. Can you verify (1) is it accurate (2) pretty sure I found it pertaining to Flooded. Would AGM, GEL be similar or would you need new chart? Lithiums?

That's a handy chart Those are the same 70 degree F voltages seen in many charts on the internet. My guess it is for wet cell batteries. The add or subtract one tenth of a volt adjustment per 10 degrees F is also mentioned on other web sites.

AGM's would have slightly higher voltages from what I've read.

That chart would not apply to lithium batteries.

Trojan - Trojan Battery Company - gives guidelines for charger settings.

There are lots of charts that indicate higher voltages are needed:

Phillips chart:

Phillips State of Charge chart flooded and agm.JPG

Interstate chart - http://www.interstatedealers.com/pdf/200004.pdf

interstate chart.JPG

phred's chart - Batteries -- and Other Electric Stuff by phred

phred chart.JPG

Edit: I should add that I like the no load 12.2v = 50% SOC at around 70F charts. I made best guess chart for my battery bank here: http://www.classbforum.com/forums/f5...html#post16223

[BobB]

avanti,

Nothing showing up on the forum

When I hit the "qoute" button to reply, this shows up

Originally Posted by avanti

If I paste that http: address in my browser, I get nothing.

Can you just post the original jpegs?