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harleylip · 08-25-2013, 06:47 PM

I recently purchased a solar set from Zamp Solar. It is a 450 watt , 25.6 amp with a 30 amp control panel . It is all mounted and appears to be working . BUT , when I try going solar , after 4 hours however , my batteries are at 50 per cent . I have a tiffin phaeton with residential refrigerator. 6 - 6 volt house batteries. My testing is with nothing on except for frig and one tv on . Has anyone got any help they might be able to send my way ?

vsheetz · 08-25-2013, 08:41 PM

All the details of your equipment, how configured, and installed are needed to help. Do you have a way to monitor the system to see the generation and consumption? Did you do the actual installation yourself or was it installed for you?

This system?
Hardwired Solar Kits | Zamp Solar

harleylip · 08-25-2013, 09:17 PM

Yes , that is the system . My refrigerator draws 11.6 amps. We put on one TV and the satellite box . We turn off water heater, AC's and nothing else is on. Yet after about 5 hours my batteries go down about 50 percent. The charging panel say it is charging at 300 watts and 19.2 amps.

vsheetz · 08-25-2013, 09:44 PM

What type batteries? How are you determining the batteries are at 50%?

19.2 amps sounds in the ball park for bulk charging rate. Does is ever go out of bulk charging mode?

11.6 amps for the frig is not the continuous consumption over time, rather worst case when the compressor is running - correct?

Christian51 · 08-25-2013, 09:44 PM

I'm no expert but from my study of the issues, you can't run your TV on that, just the ice box if you are getting full sun but most would consider that a battery trickle. I'm looking at ways to get double that or more and still would not expect to run a TV with Ice box and other small draws from the motor home. But I may be wrong. let the experts pipe in. You didn't say what kind of TV either.

There is also the issue of how much of that power your batteries can take in at what rate with the draws you have on. That has lead me to look at changing to lithium batteries when I find the right solar setup. I find it all an interesting puzzle.

harleylip · 08-25-2013, 09:53 PM

They are interstate batteries . I have 6 -- 6 volt. In the motor home is my zantrex battery monitor and that shows the level of battery . That is what is showing the 50 percent drop.

vsheetz · 08-25-2013, 10:14 PM

Quote:

Originally Posted by harleylip

They are interstate batteries . I have 6 -- 6 volt. In the motor home is my zantrex battery monitor and that shows the level of battery . That is what is showing the 50 percent drop.

Batteries - wet cell, AGM? And what are the charging rates configured?

Is the zantrex battery monitor one with a shunt? If so, what is the battery consumption in amp hours over the four hours? Does it align to the battery bank capacity?

I am trying to get to what is the real power consumption. If not excessive, then whether the batteries are not getting a full charge or not taking a full charge.

mgscott4 · 08-26-2013, 01:37 AM

At 300 watts you should be about even or slightly on the charging side, not discharging, something is wrong.

To evaluate your system, you need to start with a full charge on your batteries, that means bulk charging with high current, then acceptance (or absortion) mode, with higher voltage like 14.4-14-8 volts with a decrease in current as the batteries top off for at least 1.5 hours, then trickle at 13.4- 13.6 volts.

When was the last time the batteries were equalized? With 6 batteries it is important.

Even though the connections may look clean, they may need to be cleaned.

The following is my experience with 4 -6 volt golf cart wet cell batteries and Solar.
A battery that has had a full charge, (after bulk charging, it had an acceptance charge of 14.4-14.8 for at least 1.5 hours -2.5 hours, (The charger determines the time needed) and now is trickle charging around 13.5 volts will stay around 13.4-13.0 for a long time when you start discharging it. But a battery that did not get that peak voltage in it, will still read 13.2 - 13.4 volts indicating full charge, but will drop fast 12.6 to 12.4 volts when you start discharging it at the same rate as before. (50% charge is about 12.0-12.2 volts)

That peak voltage is very important to fully charge your batteries. I see this on my 735 watt system, when I am boondocking for many cloudy days in a row, while I am drawing 20 amps per hour out of the system for 24 hours continuous. There are times that I am not getting the peak voltage because my system will stay in bulk charge too long, and won't go to acceptance mode until late in the afternoon or not at all, and then the sun is lower on the horizon and I start discharging again and my batteries drop fast over nite.

So to evaluate your solar system, check out your batteries first, and watch the charging voltage and current to make sure you are getting a full charge.

One final note, my system takes a long time to fully charge 4-6 volt batteries, it will take even longer to charge 6 batteries. My MPPT charging system will put out as much as 50 amps in full sun, and it still takes most of the day when I am continually using 20 amps. Using 20 amps continuously is part of the problem when trying to get to the acceptance mode.

30 amps is really not that much charging amps for 4 -6 volt batteries when the batteries are discharged to 50%, they can handle 80 amps continuous charging amps for about an hour before the I see the charging current decrease while bulk charging from shore power and my Xantrex freedom 458 Inverter/charger.

If you have AGM batteries the voltage numbers and charge levels will be different, this my experience with wet cell batteries.

harleylip · 08-26-2013, 08:25 PM

Wow, I'm really confused now . Lets see , they are six, 6 volt batteries, wet cell, the connections are all clean , since they charge fine on shore power. As far as amp consumption, I have no idea how to figure that out . I started with a full charge, turned off shore power and turned on solar panels . The control panel showed 19 amps and about 250 watts. After 4 hours or so , those numbers are about the same , but my zantrex monitor in the coach shows 50 percent . I'm in South Dakota . Are there any techs out there that are close by to help ? I don't know how to check the things you guys suggested .
Confused .

mgscott4 · 08-27-2013, 03:19 AM

Your Solar panel can tell you the output of the panels but is it getting to the batteries?

Check your voltage at the batteries.

If you have a current meter, then check your current too.

I saw on the Zamp page that they use a 30 amp circuit breaker mounted close to the batteries, check that circuit breaker.

There is another 30 amp circuit breaker in the combiner harness between the control panel and the combiner, check that one too. Although, since your panel reads 300 watts 19 amps output, that one is probably good.

caissiel · 08-27-2013, 09:48 PM

I have 2 12volts batteries and a 200 Watts MPPT solar system and at noon the monitor shows batteries at 13.2 volts. And the monitor shows around 60% SOC. At dust it shows about 55% and 12.8v and my trailer monitor is green. As if batteries are charged. I just disregard the SOC and observe the voltages.

Ken-55 · 08-27-2013, 10:06 PM

At the risk of confusing you even more . . . I'm going to point you to an expert . . .

Handy Bob Solar

Lots to read and absorb but well worth the effort.

mgscott4 · 08-27-2013, 10:19 PM

That's what I have been saying. Read his section on "The RV battery Charging Puzzle" and read the "Voltage" section.

You have to charge the batteries with 14.4-14.8 volts and hold them there for 1 to 2 hours to fully charge your batteries.

jasright · 08-28-2013, 03:29 PM

Regular lead acid batteries have to n e topped off at a higher rate to completely recharge. Check with the company who sold them to you. Another reason I'm getting LFP lithium batteries. They charge completely at whatever rate is available.