Inverter voltage and new volt batteries

[Mark S]

I changed out my 4 OEM Harris 12 Volt batteries to 4 Duracell 6 volt 115 amp hour golf cart batteries. I checked all voltages and even used my hydrometer to test the batteries. All good.


When plugged in and charging, the inverter reads 13.5 volts. When I unplug the AC power, the inverter voltage drops to 12.7 -12.6 volts. I plugged in a fan that according to my Progressive Industries readout pulls about 3 amps. Within about 15 minutes the inverter readout dropped to 12.5-12.4 volts, meaning I should probably recharge the batteries soon.

What the heck?!?!? This does not sound right to me. Suggestions?

Thanks

[RVermont]

I have the same with the new batteries. Voltage drops pretty quickly to 12.5. I have not had a chance to let this go very long as it was hot and humid so I fired up the generator. I am hoping that the initial drop slows down stays around 12.4-12.5 and the recharge level will take a day to get to. I plan on recharging at 12-12.1 which is supposedly 50% charge. I was expecting 12.7 for several hours but if others are seeing the same then I will just learn the new normal.

[Mark S]

The inverter reads 12.4. I just took a meter to the batteries. Each 6 volt reads 6.3 volts. Across the batteries in series I’m reading 12.58. So I guess just the reading on the inverter is lower by 0.2 volts. Voltage drop or read out is off.

Update: After a couple of hours running the 3 amp fan the and lights, the battery readout is 12.48. So I don’t know what to think except at this point it is what it is.

[Mustang65]

Per Trojan Engineering ,

Copied from THE RESULTS ARE IN (Battery Test)



Actually brand new Deep Cycle battery takes 75 - 100 cycles to reach peak performance. On the first cycle you can expect the new batteries to provide only 70 - 75% of their rated capacity, according to Trojan engineering.

Don
My Registry

RVing with SOLAR

[Robbbyr]

Mark - You will find Don is "The Man!" when it comes to issues like this. He is saying you need to get out and exercise those new batteries! So come to Maine in early August and I will include you in my birthday plans!

On a serious note, it did take time for my Trojans to optimize themselves too.

[Mark S]

That’s good to hear. Thank you.

Now what is considered a cycle. A few minutes and then a recharge or down to 50%.

Either way I am happy to hear this.

[Mustang65]

Originally Posted by Mark S

That’s good to hear. Thank you.

Now what is considered a cycle. A few minutes and then a recharge or down to 50%.

Either way I am happy to hear this.

I am glad that you ask easy questions. Here you go, there are 3 parts (only because I can only type in 1000 characters in a "COMMUNITY" post) to my answer in the RVing with SOLAR community group.


Battery Talk - What is a "Charge Cycle" (Part-1)

Battery Talk - What is a "Charge Cycle" (Part-2)

Battery Talk - What is a "Charge Cycle" (Part-3)



Don

My Registry

RVing with SOLAR

[Robbbyr]

Originally Posted by Mark S

That’s good to hear. Thank you.

Now what is considered a cycle. A few minutes and then a recharge or down to 50%.

Either way I am happy to hear this.

What I did to "break in" in my Seneca batteries while camping was to shut off my breakers that supplied the inverter circuits and my converter. Both are in my main panel, I have a second subpanel (which I left alone) that feeds the inverter-supplied circuits, i.e. the convection microwave and the TVs. That stops the battery charging and forces the 12-volt loads to the batteries and the inverter supplies its circuits. My air conditioners and (electric) water heater element, and combo washer/dryer were still on shore power. Then we would cook dinner, watch TV, and do the regular routine using the batteries. Before "lights out" I would measure the voltage, a couple times it was around 12.1. Usually higher. So then turn back on breakers and go to bed.

My batteries got noticeably better in about 10 cycles.

[RVermont]

The amount of information on this site never ceases to amaze me. Post a question and you have good thoughtful responses within a short period of time. Thanks everyone for clarifying this information. Good project for the next week or so.

[Stargazerandu]

Originally Posted by RVermont

The amount of information on this site never ceases to amaze me. Post a question and you have good thoughtful responses within a short period of time. Thanks everyone for clarifying this information. Good project for the next week or so.

No kidding!! This site is great! All of my questions have been answered and then some!!

[Mustang65]

Originally Posted by Mark S

I changed out my 4 OEM Harris 12 Volt batteries to 4 Duracell 6 volt 115 amp hour golf cart batteries. I checked all voltages and even used my hydrometer to test the batteries. All good.

What the heck?!?!? This does not sound right to me. Suggestions?

Thanks

Also, after re-reading your post, I noticed that you have 115Ah's batteries. In conversations in this forum, regarding deep cycle batteries, most have the Trojan T105 (220Ah) batteries, which gives them about 100 more Ah than your batteries. So, when they say they get x amount of time while dry camping, you need to understand that your batteries will provide less time than theirs, and as you already know about the battery 50% rule, at 12.2 volts, you start to shut down your 12 volt system, which also equates to only having 57Ah's of the 115Ah's that you can use.

Best bet, if you are not using it (lights, radio.... ) turn them off.

Ask Santa for 100 watt Renogy Solar panel kit. Mount it on the roof and it will keep those batteries fully charged.

Don
My Registry

RVing with SOLAR

[GrumpyDad]

Originally Posted by RVermont

The amount of information on this site never ceases to amaze me. Post a question and you have good thoughtful responses within a short period of time. Thanks everyone for clarifying this information. Good project for the next week or so.

+2

[Robbbyr]

Originally Posted by Mustang65

Also, after re-reading your post, I noticed that you have 115Ah's batteries. In conversations in this forum, regarding deep cycle batteries, most have the Trojan T105 (220Ah) batteries, which gives them about 100 more Ah than your batteries.

Looking at Mark's batteries I think he may have inadvertently misstated his new batteries Ah rating. His picture shows the Duracell GC2 batteries which I believe have a 215Ah rating. So only a touch less than the Trojans.

Breath easy Mark, they will be considerably better than your old "dual-purpose" 12-volt batteries!

[Mark S]

Originally Posted by Robbbyr

Looking at Mark's batteries I think he may have inadvertently misstated his new batteries Ah rating. His picture shows the Duracell GC2 batteries which I believe have a 215Ah rating. So only a touch less than the Trojans.

Breath easy Mark, they will be considerably better than your old "dual-purpose" 12-volt batteries!

Yup, I did misstate. I’m not sure where I got the 115 number from. I sure am glad I have you guys to keep me honest.

Thank you for all the helpful information.

[Mark S]

Originally Posted by Robbbyr

Mark - You will find Don is "The Man!" when it comes to issues like this. He is saying you need to get out and exercise those new batteries! So come to Maine in early August and I will include you in my birthday plans!

On a serious note, it did take time for my Trojans to optimize themselves too.

Rob,
Maine is sooo last summer. LOL. I would have loved to join you for your BIG birthday celebration, unfortunately we will be in Angel Fire New Mexico in August, which is kind of from Maine.

We need to start working on your Florida winter trip soon.

Sounds like you have another great summer planned. Enjoy

[Mustang65]

Originally Posted by Mark S

Rob,
We need to start working on your Florida winter trip soon.

Glad to hear it was a "User Entry Error" on the 115 Ah's.

As for the Florida Winter trip, that should have been started 11 months before the anticipated vacation time as all the State CG's are booked 11 months in advance. Now the only way to find a good spot is by cancellations, which you need to check each day.

We live in west central Florida and like to go south in the winter. We got so disgusted in trying to book cg's there we stopped going, and stay in the COLD central Florida house, using heat for those couple of weeks.

Good LUCK!!
Don

My Registry

RVing with SOLAR

[Mark S]

[QUOTE=Mustang65;653785]Glad to hear it was a "User Entry Error" on the 115 Ah's.

As for the Florida Winter trip, that should have been started 11 months before the anticipated vacation time as all the State CG's are booked 11 months in advance. Now the only way to find a good spot is by cancellations, which you need to check each day.

We live in west central Florida and like to go south in the winter. We got so disgusted in trying to book cg's there we stopped going, and stay in the COLD central Florida house, using heat for those couple of weeks.

Good LUCK!!
Don

Sadly, you are correct about the campgrounds filling up Don. RVing is getting too popular. This will be our 7th summer of escaping the heat (we are now Sun Birds, the opposite of Snow Birds) and each year it is getting more difficult to find camp sites. The first couple of years we never made reservations and this year we are booked for almost the entire trip and I hate locking ourselves in like that.

And as far as you escaping the frigid central Florida winters, I think we average about 8 degrees difference from you. Now Rob, in Akron, Ohio, it might be more like 12 degrees LOL.. Don’t worry Rob, I have spot in my yard for you

When you are living off your batteries, what appliances do you use? For instance, do you microwave or make coffee off your system or do you fire up the generator for certain items? My thinking is the only thing I really need the generator for would be the air conditioner. I am really trying to get an understanding of the system limitations.