New Batteries Won't Fully Charge

D

dharte

Senior Member
Joined
Dec 8, 2015
Messages
161
Hi Folks,
As mentioned in a couple of recent posts, I added a small 12v, 2-way fridge and upgraded from a single 12V battery to a dual 6V system. My amp-hour capacity went from 75 to 210. Now my 160w solar charger never gets to float mode (where it says batteries "full"). There are 4 battery indicator LED's and it's always on the 3rd one indicating about 3/4 charge. With the old battery it was almost always at "full" when the truck/camper were parked and not being used. On the FWC panel that indicates battery life and water tank level, it shows the batteries are fully charged. I have tested the batteries and they both read close to 7v each. I have driven the truck a bit, but no long drives (over an hour) that might allow the alternator to fully charge the batteries. I also realize it's only March, and we have had some rainy weather, so perhaps in peak sun in the summer the solar panel would fully charge the batteries, but it concerns me because I do a lot of fall and spring camping. So I have a few questions i hope you guys can help me with.

1. How fast should the 120v inverter charge the batteries? I have left it plugged in for over 12 hours and it still won't reach "full" on my solar charge controller display.

2. Would adding a 100W portable panel help significantly? I have the plug on the rear wall of the camper to plug into. If so, any recommended brands that would be easy to transport (folding)?

3. Is it bad for the new batteries not to get to fully charged (float) status?

thanks,
David
 
David,

What solar controller are you using? Is it programmable for the type of batteries you have?

What battery monitor are you using? Does it only have LED lights and no readout of the actual voltage?

What kind of batteries are you using?

(you may have given that information in a different topic post but I do not remember your setup)

In the end analysis all lead acid batteries FLA, AGM and Gel need to be properly multi-stage charged as well as maintained at a float charge to yield maximum life. I am not nearly as informed on the charging needs of LiFePO4 batteries - yet.


I am confused by your question: "How fast should the 120v inverter charge the batteries? "

An inverter changes DC to AC (12 V DC to 110 AC) . So the inverter will not charge your batteries. It will discharge them.

Did you mean converter which changes AC to DC? As in a battery charger plugged in to the house AC 110 V?

or perhaps you were referring to the Solar Charge controller (DC to DC).?

When disconnected your 6V batteries should have about 6.37 V (open circuit). When connected and float charging they should each be above about 6.9v - the exact number depends on battery type.




Craig
 
ckent323 said:
David,

What solar controller are you using? Is it programmable for the type of batteries you have?

What battery monitor are you using? Does it only have LED lights and no readout of the actual voltage?

What kind of batteries are you using?

(you may have given that information in a different topic post but I do not remember your setup)

In the end analysis all lead acid batteries FLA, AGM and Gel need to be properly multi-stage charged as well as maintained at a float charge to yield maximum life. I am not nearly as informed on the charging needs of LiFePO4 batteries - yet.


I am confused by your question: "How fast should the 120v inverter charge the batteries? "

An inverter changes DC to AC (12 V DC to 110 AC) . So the inverter will not charge your batteries. It will discharge them.

Did you mean converter which changes AC to DC? As in a battery charger plugged in to the house AC 110 V?

or perhaps you were referring to the Solar Charge controller (DC to DC).?




Craig
Click to expand...
Thanks for your input Craig. I am using the Zamp 30a controller that came with my 2015 Hawk. It's not programmable other than being able to select the type of batteries, which I correctly have set at AGM. The batteries are Amstron AGM's. What I meant by the inverter is the 120V shore power plug. I thought this will charge the batteries when it's plugged in. My old Jayco tent trailer had this feature and that's how I charged the battery before camping since I didn't have solar. .
 
When you are plugged into 120, disconnect the battery and check the voltage coming out of your converter. It should read 14.5 on flood, or 13.5 on float. I had a problem with my new Grandby last year where I discovered there was no voltage coming off the converter and going to the battery. Turns out there was a problem in the wiring between the converter and the battery.

The converter should bring your batteries up to float.

Without the converter plugged in, I think it will take some sunny days to get the battery up to float, especially if the fridge is running.
I have a 100W Aux Panel that really helps.

Do you have anything blocking your 160 watt panel? Anything at all will drastically cut down the amperage going to the controller.
 
Keep in mind that the Iota is a smart charger and makes its own decision about when to stop charging and switch to float. A Zamp charge controller will show 13.5 to 13.7 volts when the Iota has switched to float mode.

After several days still plugged into shore power, the Zamp may indicate fully charged. However, the solar charge controller is making its own separate decision about full charge. Time being charged, voltage reached, and current still being accepted by the battery all go into the decision to display fully charged.

Also, I suspect that the greatly increased battery capacity of your new batteries may be affecting the charge controllers decision based on its history with the battery they replaced. It may take some time for it to adjust to the new battery capacity.

The camper’s multifunction panel is overly optimistic and based solely on voltage. I use it solely for water level.

To really know your SOC, (state of charge), you need s true battery monitor like the Trimetric or Victron units.

Paul
 
dharte,

By shore power plug do you mean the built in camper battery charger? Does your camper have the IOTA DLS-30? If so does it have the IQ-4 module?

The important part about charging AGM batteries is to not overcharge them They do not like that and it will shorten their life.

I am not familiar with the Zamp Solar Controller other than to just recognize the name.

If your controller is working properly and your system is connected properly and you do not have any loads on then the Solar panels should bring the batteries up to full charge and maintain them at a float voltage.

More questions:

You wrote "my 160w solar charger never gets to float mode"

How many watts of panels do you have?


Are your two 6V batteries wired in series?
 
camper rich said:
When you are plugged into 120, disconnect the battery and check the voltage coming out of your converter. It should read 14.5 on flood, or 13.5 on float. I had a problem with my new Grandby last year where I discovered there was no voltage coming off the converter and going to the battery. Turns out there was a problem in the wiring between the converter and the battery.

The converter should bring your batteries up to float.

Without the converter plugged in, I think it will take some sunny days to get the battery up to float, especially if the fridge is running.
I have a 100W Aux Panel that really helps.

Do you have anything blocking your 160 watt panel? Anything at all will drastically cut down the amperage going to the controller.
Click to expand...
Good idea camper rich-I will test this today to see if the converter is supplying voltage to the batteries. The fridge (and everything else except the propane/CO alarm) is off so that shouldn't draw any current. I do have a tree blocking late PM sun but it gets at least 8 hours of sun where it is parked in my driveway. Meanwhile I will shop for a portable panel.
 
dharte,

If you have the IOTA battery charger and you have AGM batteries it is important that the IOTA unit also have the IQ4 smart charger either built in or the optional plug in installed (available from Amazon) otherwise it will overcharge your AGM batteries.

When your 6V AGM batteries are connected in series and at float they should be at about [SIZE=12pt]2.25 V to 2.3 V per cell. This voltage may be slightly different for your specific battery so best to check your manufacturer [/SIZE]recommendations

[SIZE=12pt]3 cells x 2.25 V = 6.75 V (6 cells when wired in series x 2.25 v = 13.5 V) minimum[/SIZE]

[SIZE=12pt]3 cells x 2.3 V = 6.9 V (6 cells when wired in series x 2.3 V = 13.8 V) maximun[/SIZE]

If your batteries are going to more then 13.8 V you may be cooking them (unless your manufacturer recommends a slightly higher float voltage)

It occurs to me that if the Zamp controller only has led indicators and has settings for FLA and AGM that the full charge indicator may not go on for AGM since the float charge voltage is lower for AGM than for FLA. I am just guessing at this. In any event LED lights do not provide sufficient information to understand if your system is functioning properly.

I recommend getting a battery monitor for your house bank.

You can get an inexpensive one with a shunt like the Bayite here:
https://www.amazon.com/gp/product/B013PKYILS/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

or you can get one that is programmable for your batteries and with logging function and bluetooth so you can easily check it anytime such as the Victrom BVM-712 or the BVM-700 or BVM-702 (without bluetooth - but it can be added later)

http://shop.pkys.com/Victron-Energy-BMV-712-Smart-Battery-Monitor-with-Bluetooth-PN-BAM030712000-_p_6968.html?gclid=EAIaIQobChMIi5CZ6fPz2QIVSmx-Ch3NJweuEAQYASABEgJaZvD_BwE




Craig
 
To be honest, I'm not sure which charger (IOTA?) I have. Would this be visible somewhere in the cabinetry? I have no owner manuals for this component. This morning I went out to check the system and the Zamp is reading 14V, and is still on 3/4 full indicator. I just ordered a Victron monitor so I will no longer have to guess what is really going on with the batteries.
 
dharte,

The charge controller for the camper that uses shore power is often located at the bottom of the cabinets to the left of the sink between the sink and the refrigerator (in models having that configuration).

The cabinets in my camper are open at the bottom and if I lay on the floor I can look up behind the front face of the cabinets and see the shore power charge controller. You will need a good flashlight.

In the event you cannot determine which controller and assuming you have an FWC camper there should be a tag on the lower outside back wall usually to the right of the door that gives the model and serial number of your camper.

Contact FWC, give them that info and ask what charge controller is in your camper.

This is important to sort out.

BTW: What year and model is your camper? If made in the past few years it may have the Iota with IQ4 module. If older and it has the IOTA unit it will not have the IQ4 module unless the previous owner installed one. You will need to look at some pictures to compare to what is there to understand if the IQ-4 module is installed or not I think there are some here on WTW if you do a search.


I do not think your batteries will be damaged in the short time it takes you to sort this all out (assuming less than a month).

Which Victron monitor did you get? I have the BVM-702 with the bluetooth dongle but now that the BVM-712 is available I would opt for that instead if I were doing it all over again (it came out about a month after I bought and installed my 702). Ugh!

Craig
 
ckent323 said:
dharte,

The charge controller for the camper that uses shore power is often located at the bottom of the cabinets to the left of the sink between the sink and the refrigerator (in models having that configuration).

The cabinets in my camper are open at the bottom and if I lay on the floor I can look up behind the front face of the cabinets and see the shore power charge controller. You will need a good flashlight.

In the event you cannot determine which controller and assuming you have an FWC camper there should be a tag on the lower outside back wall usually to the right of the door that gives the model and serial number of your camper.

Contact FWC, give them that info and ask what charge controller is in your camper.

This is important to sort out.

BTW: What year and model is your camper? If made in the past few years it may have the Iota with IQ4 module. If older and it has the IOTA unit it will not have the IQ4 module unless the previous owner installed one. You will need to look at some pictures to compare to what is there to understand if the IQ-4 module is installed or not I think there are some here on WTW if you do a search.


I do not think your batteries will be damaged in the short time it takes you to sort this all out (assuming less than a month).

Which Victron monitor did you get? I have the BVM-702 with the bluetooth dongle but now that the BVM-712 is available I would opt for that instead if I were doing it all over again (it came out about a month after I bought and installed my 702). Ugh!

Craig
Click to expand...
I ordered the same one you have (702)-don't really need the Bluetooth (but can add later). I am the original owner-camper is a 2015 Hawk front dinette. My concern now is that if the Zamp thinks the batteries aren't charged and they are, it won't go into float mode and my batteries get overcharged. I guess I won't know for sure until I install the monitor. BTW, how big a hole is needed to install the Victron in a cabinet? Thanks again everyone for your help-this sight is great for quick feedback!
 
OK, this is weird! I did the test that camper rich suggested (disconnecting batteries and measuring shore power voltage). The shore power voltage was 14.8V. When i unplugged the shore power and reconnected the batteries the Zamp display indicated full! Maybe it just had to reset or something......Anyway this is the first time it's displayed full so perhaps my problem is solved. I still think I may get a portable solar panel to add more power to the system.
 
dharte,

14.8 V going to your batteries will cook them, that is too high for AGM float.

My guess is that you have the IOTA DLS-30 withouot the IQ4 module. You may need one of these if you have an IOTA unit. The IQ4 limits the float stage to 13.6 V. (IQ4 bulk charge is 14.7 V)

https://www.amazon.com/IOTA-Engineering-IQ4-Smart-Charger/dp/B0030G7ZHM

It just plugs in - the hardest part is finding the plug in jack on the IOTA DLS-30

Here is the IQ4 spec sheet link:

https://www.solar-electric.com/lib/wind-sun/iq4spec.pdf


BTW: IOTA now makes different IQ modules for specific batteries (FLA, AGM, GEL and LiFePO4)

I do not know if the IQ-AGM is appropriate as I just learned of it but it is worth looking into.

https://www.solar-electric.com/lib/wind-sun/IOTA_IQ_profiles.pdf

You can buy it here for $19

https://www.solar-electric.com/iota-iq-agm-dls-controller.html?gclid=EAIaIQobChMIpKyWqoz02QIVhWx-Ch1A8Q_PEAYYASABEgJn2PD_BwE
 
dharte said:
OK, this is weird! I did the test that camper rich suggested (disconnecting batteries and measuring shore power voltage). The shore power voltage was 14.8V. When i unplugged the shore power and reconnected the batteries the Zamp display indicated full! Maybe it just had to reset or something......Anyway this is the first time it's displayed full so perhaps my problem is solved. I still think I may get a portable solar panel to add more power to the system.
Click to expand...
I would wait on adding portable panels until you figure this out and get some time using the camper in the places you like to camp.

And no surprise on the disconnect changing things. That gave the zamp a chance to recalibrate, as Craig suspected above.

14.8 is a bit hot, but that was when no batteries were connected. Connect them again and measure the float voltage and report back.

Victron 702 is a great unit!
 
Today I went out to our new to us Hawk flatbed 2015 model and took the covers off to see how FWC wired everything up. I noticed the Iota is model DSL30 / IQ4. So it has the IQ4 built into it. If I wanted to install the new AGM IQ4 will it override the internal system?
 
Note: External IOTA IQ Smart Charge Controllers are not compatible with DLS with internal IQ charge control.

Found the answer on their web page
 
You must log in or register to reply here.

Similar threads - WTW

Robojeeper53
Old and new battery mix?
Wandering Sagebrush
Wandering Sagebrush
Z
2006 FWC Electrical Issue
Wandering Sagebrush
Wandering Sagebrush
K7MDL
Installed Renogy One Core monitor and Battery Shunt 300
K7MDL
K7MDL
D
2024 Improvements to 1966 8' NCO Alaskan
Denver Alaskan
D
O
MPPT controller at 13.64v - Blue Sea meter at 12.35v - Batteries not charging
Jon R
J

New posts - WTW

Back
Top Bottom