Can't adequately charge batteries.

RobertR · November 2013

I have 4 Trogen 6v golf cart batteries (new) hooked to deliver 12v, (series parallel) , Morningstar MPPT 60 amp controller, and two 350 watt panels hooked in parallel.
Previously the panels were about 25 feet from the controller connected with #12 wire. I was getting ~ 10 amps of charge. I did not think this was very good as I should be getting 40 to 60 amps. So I moved the panels closer to the controller and installed #2 welding cable. Distance from panels to controller is ~ 5 foot, distance from controller to batteries is ~ 5 foot.
After installing larger wire and moving panels closer, max charging amps I can now get is ~ 5 amps.

I have to run the generator approx. 2 hours a day to charge batteries after an ~ 30 or 40 amp hour drain. Charging with solar all day long on sunny day will not bring amp hours back to zero.

Other curious note. The remote meter has to be plugged in backwards to work. i.e. the lead from the Tri Star has to go into the meter port, backwards of what the directions say.

The 14.7v setting toggle switch on the Tri Star sets off a fault. So I am set on 14.6v

The battery amp hour reading on the Tri Star meter says I have ~ 1000 amp hours of batteries but I in fact only have ~ 450. I do not see a way to change this. All directions tell how to do is reset amp hours in verses amp hours out back to zero.

Cariboocoot · November 2013

Re: Can't adequately charge batteries.

What you can expect out of 350 Watts of panel on a 12 Volt system: 22 Amps. Not anyplace near 40 or 60 Amps and not even minimum for 450 Amp hours @ 12 Volts (the batteries you say you have). You do not have 1000 Amp hours; only the parallel battery connections increase Amp hours, the series connections increase Voltage (two 6 Volt 225 Amp hour batteries in series make 12 Volts @ 225 Amp hours).

There is no reason to expect your set-up to work for charging that much battery.

Exactly what the panels are in spec and how they are connected will make a big difference in power loss across 25 feet. For example if they are all in parallel then the wire has to take the full current and the V-drop will be enormous. I doubt you can get a decent connection to welding cable at either end of this; best not to use it. Normally 10 AWG is used, but again it depends on the array configuration.

It is possible that in changing the array wiring you may have inadvertently reversed a panel connection, negating some of the power.

I don't know why the TriStar meter would say anything about Amp hour capacity because it has no way of knowing what that is, nor does it care. Do you perchance mean a Trimetric meter?

NorthGuy · November 2013

Re: Can't adequately charge batteries.

Either you miswired something or you have bad parts (controller, batteries).

Can you disconnect panels and measure Voc and Imp with a multimeter?

stephendv · November 2013

Re: Can't adequately charge batteries.

Since you have a tristar MPPT controller, you can connect the panels up in series instead of parallel to reduce wire losses. Also, when reading the Amps from the controller note what the battery voltage was at the time of the current reading. If the battery is in absorb or float, then it will reduce the current from the panels. You'll only see maximum current during bulk phase of charging.

vtmaps · November 2013

Re: Can't adequately charge batteries.

RobertR wrote: »

two 350 watt panels hooked in parallel.

Cariboocoot wrote: »

What you can expect out of 350 Watts of panel on a 12 Volt system: 22 Amps.

Robert, you should be able to charge those batteries with 700 watts of panel. First you should heed stephendv's advice and confirm that your battery is in bulk charge when you read the amps. If your low output persists, its time to pull out the digital voltmeter and take some measurements... we can help walk you through that.

RobertR wrote: »

The 14.7v setting toggle switch on the Tri Star sets off a fault. So I am set on 14.6v

The battery amp hour reading on the Tri Star meter says I have ~ 1000 amp hours of batteries but I in fact only have ~ 450. I do not see a way to change this. All directions tell how to do is reset amp hours in verses amp hours out back to zero.

Something sounds wrong about this, but I don't have a tri star controller, so I can't troubleshoot it.

RobertR wrote: »

I have to run the generator approx. 2 hours a day to charge batteries after an ~ 30 or 40 amp hour drain. Charging with solar all day long on sunny day will not bring amp hours back to zero.

What other equipment do you have? What regulates the charge when the generator runs?

--vtMaps

waynefromnscanada · November 2013

Re: Can't adequately charge batteries.

RobertR wrote: »

The 14.7v setting toggle switch on the Tri Star sets off a fault. So I am set on 14.6v

The battery amp hour reading on the Tri Star meter says I have ~ 1000 amp hours of batteries but I in fact only have ~ 450. .

Could you please give us the exact model # of your controller. It would also be helpful if you could supply the make and model of your PV panels.
Beyond this - - re the "toggle switch" setting a fault - - are you aware that all power must be removed from your controller before changing the position of any of the DIP switches and then the controller must be restarted by reconnecting power to it? Otherwise it will set a fault. Owners manual info.
Furthermore, I've had both one PWM and two MPPT Morningstar controllers and have never encountered anything that would indicate the controller has any idea or any way of coming up with the AH capacity of my batteries. Something isn't making sense here - - perhaps there are things you're not telling us?

Cariboocoot · November 2013

Re: Can't adequately charge batteries.

I suspect the meter info on Amp hours is from a Trimetric, not the charge controller (which does not have or utilize such info). Notice he said "The remote meter has to be plugged in backwards to work"? That sounds like the shunt is on the positive cable instead of the negative cable which would require reversing the wires on either side of the shunt to get correct function reading.

But we need more info from the OP before proceeding.

RobertR · November 2013

Re: Can't adequately charge batteries.

The charge controller is Morningstar TS MPPT 60 The TriStar solar controller is TS-M. If the solar panels have a name on them it would be on the back side, and I would have to un-install them to take a look at the back side. I bought them from UL Solar.

The electrical connections are copper vice type purchased at Home Depot. You turn the set screw to tighten / clamp the wires together. I don't see how it is possible to have a bad connection.

I am going through the settings on the controller to see if I can find the amp hour reading again, settings are :
HW v01.01 sw v12 Serial 12470566
Meter v02.00.02
Mode: Charge 12v (fixed)
Battery #5 Float 13.5v
Absorption 14.6v PWM
Equalize 15.3v Auto 28 days

The solar controller is connected to the charge controller via a 6 pin telephone wire. I looked at the directions again and they clearly say plug the telephone wire into the port that says TriStar. When I plug it into that port I get nothing. I have to plug into the port that says meter. But the directions say that port is for chaining controllers together, i.e adding another controller.

It appears that the 1000ah reading I was remembering is on my TM 2025 RV monitoring meter as I can't find it on the TriStar. It has been reset to 450 ah.

After throwing circuit breakers / disconnecting the TriStar I was able to switch to 14.7V mode. 1 problem down. Setting now read Battery #6 13.5 float
Absorption 14.7v PWM

Found the AH reading. It is under Diagnostics It now
says Total 677.5 Ah reset 544.1Ah
Next reading is TriStar: 76 degrees F 1010 hours.

If my math is correct 700w / 12v = 58 amps Should that not be the out put of the solar panels on a good day? 5 amps is less than 10% of that. What I really don't understand is why moving panels closer to the charge controller and increasing the size of the lead wires cut the amps in half.

Would I get better results if I hooked the panels in series? The only reason I can see for doing that is to reduce the size of the lead wires, but my lead wires are as big as will fit into the connectors of the TriStar MPPT. Size chosen by the size of the connector port on the controller. I always thought bigger wire was better?

Un clamped the solar panel lead wires, checked polarity of both of them. + is connected to + , - connected to -. Both were putting out 19.5v on semi cloudy day. Connected together, still get 19.5v. Lead wires entering charge controller before connecting, i.e. with circuit breaker thrown, 19.5v, no detectable voltage drop.

westbranch · November 2013

Re: Can't adequately charge batteries.

the TS-M is a digital METER...now into version 2 http://www.morningstarcorp.com/en/product-comparison?ModelId_1=7332b1ab-fff9-a236-c3b2-1a9d9155fb58&ModelId_2=&ModelId_3=

The meter will display a great deal of information about the TriStar controller and the operation of your system. In addition, the meter enables manual functions and controller diagnostics.

2manytoyz · November 2013

Re: Can't adequately charge batteries.

Still getting my hardware setup at the new house. I put 520W of panels on the roof so far, and I was able to get a 33.7 Amp charge rate. You should easily be able to exceed that with two 350W panels in parallel.

That said, my battery bank was near full during the time of testing. My actual current supplied from the panels would go from 0 Amps, to just a few Amps. To get the charge controller to open up, and allow maximum charging, I had to power up the 1800 Watt inverter, and connect a 1500 Watt heatgun. That was the ticket. It was also near the peak of the day, and I waited for the sun to poke his head out!

I don't have the same specific hardware as you, so don't know about your settings. But I'm thinking this might just be a case of the bank being almost full, and the charge controller throttling back. Just a guess...

RobertR · November 2013

Re: Can't adequately charge batteries.

If 5 amp charge is all I can get out of 700 w of panels, then to get 60 amps I would need 24 panels. i.e. 2.5 amps per panel. There is not enough room on the roof of the motor home for that. Something is not right.

I would not care what the amp out put is if I could get the controller to charge the batteries. In the evening I typical drain out ~ 40 amp hours. Its sitting on -37 right now. All day long on a sunny day will bring it back to -20 at best. I have to run the generator to get it back to zero.

I can turn the microwave on, ~ 1400 watt draw, and charge amps does not change.

NorthGuy · November 2013

Re: Can't adequately charge batteries.

RobertR wrote: »

If 5 amp charge is all I can get out of 700 w of panels, then to get 60 amps I would need 24 panels. i.e. 2.5 amps per panel. There is not enough room on the roof of the motor home for that. Something is not right.

You need to start from the beginning, that is from the panels. If your panels are incapable of producing, controller settings will not matter. You need to make sure panels are ok first. You need to get a multimeter and measure Voc and Isc on the panels. If you cannot do this, you need to hire someone who can troubleshoot your system for you.

Cariboocoot · November 2013

Re: Can't adequately charge batteries.

I have 700 Watts of panels. They are capable of over 20 Amps of current on my 24 Volt system.

Something is wrong with your system. It needs to be properly evaluated, including what the panel specs are, how they are wired, configuration to charge controller, etc. This is at the "disconnect and inspect" stage because there is no other way to determine what is going on.

NorthGuy · November 2013

Re: Can't adequately charge batteries.

Cariboocoot wrote: »

I have 700 Watts of panels. They are capable of over 20 Amps of current on my 24 Volt system.

That is because they're wired properly (I guess

) and are not defective.

2manytoyz · November 2013

Re: Can't adequately charge batteries.

RobertR,

Sounds like you've ruled out the obvious, time for a meter. Most DVMs are only rated to measure 10, or 20A. I've found a DC clamp-on ammeter very handy for troubleshooting and checking the performance of my setup.

The one I have has two scales. 40A, and 400A.

If it were me, I'd disconnect the wires going to the charge controller, from the solar panels. Short them together, and measure the current (Isc) with the clamp-on ammeter. That will quickly let you know if you are getting the rated power from your panels & wiring.

Nice part about this is this is a quick test, no need to climb on the roof, or remove panels.

FWIW, I bought this meter at Northern Tool. Many brands available thru Amazon, etc. Just make sure the ammeter you buy can handle DC. Most can only handle AC, which won't work in this application.

NorthGuy · November 2013

Re: Can't adequately charge batteries.

2manytoyz wrote: »

I'd disconnect the wires going to the charge controller, from the solar panels. Short them together, and measure the current (Isc) with the clamp-on ammeter.

A word of caution. While connecting/disconnecting panel wires, either cover panels with something or wait until dark, or you may get lots of sparks.

niel · November 2013

Re: Can't adequately charge batteries.

NorthGuy wrote: »

A word of caution. While connecting/disconnecting panel wires, either cover panels with something or wait until dark, or you may get lots of sparks.

if not then 2manytoyz can change his username to "2manysparkz".:roll::p

PNjunction · November 2013

Re: Can't adequately charge batteries.

RobertR wrote: »

Un clamped the solar panel lead wires, checked polarity of both of them. + is connected to + , - connected to -. Both were putting out 19.5v on semi cloudy day. Connected together, still get 19.5v. Lead wires entering charge controller before connecting, i.e. with circuit breaker thrown, 19.5v, no detectable voltage drop.

This is what worries me - your panels are exhibiting a voltage common to "battery panels" or "nominal 12v panels", which typically have 17 to 22 volts or so across the terminals with no load, and the highest wattage they go is about 200 watts or so. Your 350 watt panels should be "GTI" panels, and they have nearly double the voltage, so you *should* be reading somewhere around 35 - 45 volts open circuit on each - no load that is.

I think you may have gotten some nominal 12v panels installed by mistake. Either that, or there may be possible miswiring / jumpering inside the panel's junction box.

If you can't remove the panel for verification, then by all means you'll have to do the open circuit voltage, and short-circuit amperage test (no load!). What are the dimensions of these 350 watt panels? By looking at the panels our host provides for near the 300 watt range, if you see a gross difference in dimensions, that may also be a clue.

2manytoyz · November 2013

Re: Can't adequately charge batteries.

niel wrote: »

if not then 2manytoyz can change his username to "2manysparkz".:roll::p

Well, I am a sparky by trade.

Throw a blanket over 'em if you don't like a light show, LOL.

On my setup, I have a power disconnect on each set of panels. They can be disconnected with a push of a button, wires tied together, then reconnected. No spark.

RobertR · December 2013

Re: Can't adequately charge batteries.

If I am understanding right, I should disconnect leads going to controller, short circuit them and read amps. If amps are low, then crawl on roof, disconnect one panel from the other, and check short circuit amps on each panel individually.

To answer previous questions, the panels are approx 4 foot long, 2.5 foot wide each approx 2 years old. Volt reading on each panel was 19.5 but that was not on a full sun day. It was partly cloudy.

vtmaps · December 2013

Re: Can't adequately charge batteries.

RobertR wrote: »

Volt reading on each panel was 19.5 but that was not on a full sun day. It was partly cloudy.

The voltage is more affected by temperature than by light level. Almost any light at all will generate the same open circuit voltage. --vtMaps

PNjunction · December 2013

Re: Can't adequately charge batteries.

RobertR wrote: »

If I am understanding right, I should disconnect leads going to controller, short circuit them and read amps. If amps are low, then crawl on roof, disconnect one panel from the other, and check short circuit amps on each panel individually.

You got it - keep a spare fuse for the multimeter handy. If you forget to move the multimeter leads to the current-jacks, then the spare fuse comes in handy. Ask me how I know. <grin>

But like vtmaps mentions, if you've got enough light to cast even a shadow, the ocv should be right up to what the panels are rated at. I'm still suspicious of your voltages, but hoping there is something overlooked.

RobertR · December 2013

Re: Can't adequately charge batteries.

Ok I have done the following. I have a total of 6 solar panels available to test. 2 in motor home, 2 on office roof, 2 on warehouse roof. I tested them all for volts and amps, and angled toward the sun at approx same angle as the ones on the motor home they all read the same. ~ 20v and 10amps.

I then connected the 2 on the motor home in series, got ~ 40v, and 10amps. The Morning star meter said amps had dropped to 2.5. So I put them back in parallel. I then ran a wire from panels on office roof to motor home, connecting 4 panels in parallel. Meter on Morningstar did not change, it still says 5 amps charge. So I ran a wire from panels on warehouse roof and connected all 6 panels in parallel. Morningstar meter still says I'm getting a 5 amp charge.

No matter what I do I cannot get more than 5 amps out of the Morningstar controller. Battery charge monitor says I am right now at minus 45 amp hours. The only way to return that to zero is to crank the generator and run it for about 2 hours. Charging batteries all day long with Morningstar will not change the amp hours in verses out more than 5 to 6 amp hours. It never resores used amp hours to the batteries. I go in to the Motohome in the evening look at amp hour meter and it usually reads in the range of minus 30 to 40 amp hours. I then crank the generator to watch TV and return batteries to some where close to zero.

It appears to me that the Morningstar controller is not designed to charge the batteries properly? It would be my guess that I could hook 20 panels in parallel and still only get a 5 amp charge as I am getting the same 5 amp charge whether I use 2,4, or 6 panels. It looks to me like the controller is reading battery voltage and shutting down before amp hours are returned to the battery. The level of discharge of the battery, 10 amp hours, 20 amp hours, or 50, doesn't matter, the controller puts out the same 5 amps.

For the office and warehouse I am using a NC25A-12 controller, 2 of them as they are separate systems. I could move one of those to the Motorhome and see if I can charge the batteries that way.

Did I mention that i have to hook up the Morning star meter to the Morningstar controller backwards before it will work. It has two ports. One says meter, the other says Tristar. The directions clearly state that the connecting 6 pin telephone looking cable should be inserted into the port that says Tristar, and that the other port is for hooking into a second meter, i.e. chaining meters together. If I hook into the Tristar port I get nothing. If I hook into the meter port it works. Clearly backwards of what the directions say.

Cariboocoot · December 2013

Re: Can't adequately charge batteries.

Morningstar controllers are designed to charge batteries properly. Most of the people who have them have no trouble whatsoever. Every once in a while someone has trouble. Chasing down exactly what causes that trouble can be difficult, especially by 'remote control'.

The Voltage readings you were getting are Voc and meaningless in this instance. The current reading depends on how much load is on the panel. In the case of the short-circuit readings you were taking you got good results that show the panels do produce current (10 Amps) which means they can be eliminated as the source of the problem.

Charge current coming from the controller is another issue as it depends not only on the power coming in but the demand of the battery & loads. If you are measuring a maximum of 5 Amps out no matter what (including with loads turned on in addition to the battery charging demand) then something is preventing the controller from passing the 10 Amps available from the panels. One possibility here is that the controller's parameters are set wrong. How or why the maximum current could have been reduced to 5 Amps I don't know.

In your first post you mention that setting the charge Voltage to 14.7 set of a fault. That is not a good sign.

One thing you can check is to bypass the charge controller completely and see how much current flows from the panels to the battery. If it is greater than 5 Amps then it looks like the controller is indeed faulty. If it is still only 5 Amps something is seriously wrong in the wiring or batteries themselves.

Gloworm · December 2013

Re: Can't adequately charge batteries.

Cariboocoot wrote: »

One thing you can check is to bypass the charge controller completely and see how much current flows from the panels to the battery. If it is greater than 5 Amps then it looks like the controller is indeed faulty. If it is still only 5 Amps something is seriously wrong in the wiring or batteries themselves.

I might do this on my setup tomorrow, my hesitation would be the panel putting out over 20V Voc directly to a battery that is not supposed to get over 15V, but that obviously falls to VMP depending on load, right? Also, if his batteries are the issue, what are common issues that would prevent them from showing more than 5A?

Cariboocoot · December 2013

Re: Can't adequately charge batteries.

Gloworm wrote: »

I might do this on my setup tomorrow, my hesitation would be the panel putting out over 20V Voc directly to a battery that is not supposed to get over 15V, but that obviously falls to VMP depending on load, right? Also, if his batteries are the issue, what are common issues that would prevent them from showing more than 5A?

Panels are a current source: they try to produce Imp at any Voltage up to Vmp and will pretty much let the Voltage go where it will. When you attach one directly to a battery the Voltage will be pulled down to Battery level and the current will come up (assuming sufficient illumination).

Note that a PWM charge controller does connect the two directly during Bulk, and modulates this connection ON/OFF to regulate Voltage for Absorb and Float stages. An MPPT controller is more complicated as it will convert higher Voltage to greater current so the connection isn't exactly the same.

A battery with unusually high resistance will draw very low current. Heavy oxidation, plate failure, low electrolyte are some of the things that can cause this. Plate failure would be the most difficult to detect, and most often they short out causing lower resistance rather than drop out causing higher resistance.

One way to check the batteries is to try charging from an alternate source and see what happens. It's always a good idea to have an alternate source, especially if you're off grid 50 miles from civilization.

vtmaps · December 2013

Re: Can't adequately charge batteries.

RobertR wrote: »

Battery charge monitor says I am right now at minus 45 amp hours.

Why do you think the monitor is correct? Perhaps you can't get any charge into the batteries because they are nearly charged already.

--vtMaps

RobertR · December 2013

Re: Can't adequately charge batteries.

vtmaps wrote: »

Why do you think the monitor is correct? Perhaps you can't get any charge into the batteries because they are nearly charged already.

--vtMaps

If the batteries were fully charged by the end of the day, then turning on the generator would not charge them more. i.e. put more amp hours back into the batteries. The battery monitor meter is a TM 2025-RV which keeps a running total of amp hours in verses out.

Today in the morning the amp hours were minus 44.6 8AM. At the end of the day they were minus 40.1 at 5 PM. Thus the solar panels put 4.5 amp hours back into the battery during the day.

Watching TV at night on inverter uses ~ 45 amp hours. Thus I am putting back about 10% of what was taken out. Running the generator for ~ 2 hours will return the amp hour reading to zero.

Generator is running now and it is putting ~ 50 amp into the batteries.

RobertR · December 2013

Re: Can't adequately charge batteries.

I checked the toggle switches again. They are
1 off Solar Charging
2 off Auto Voltage
3 off Auto Voltage previously set to on for 12v, but does not make any difference
4 on battery type 6 Flooded 14.7v absorb
5 off
6 on
7 on auto equalize
8 off

I origionally had volts set to 14.6 as that is what Trogen recommends, but decided to try 14.7v setting because batteries were not being charged. I flipped the switch with out disconnecting breaker and got a fault. Then was informed I did it wrong. Turning off breaker before changing toggle settings worked.

I also toggled to auto from 12v to see if that made any difference. It didn't.

RobertR · December 2013

Re: Can't adequately charge batteries.

Cariboocoot wrote: »

Morningstar controllers are designed to charge batteries properly. Most of the people who have them have no trouble whatsoever. Every once in a while someone has trouble. Chasing down exactly what causes that trouble can be difficult, especially by 'remote control'.

The Voltage readings you were getting are Voc and meaningless in this instance. The current reading depends on how much load is on the panel. In the case of the short-circuit readings you were taking you got good results that show the panels do produce current (10 Amps) which means they can be eliminated as the source of the problem.

Charge current coming from the controller is another issue as it depends not only on the power coming in but the demand of the battery & loads. If you are measuring a maximum of 5 Amps out no matter what (including with loads turned on in addition to the battery charging demand) then something is preventing the controller from passing the 10 Amps available from the panels. One possibility here is that the controller's parameters are set wrong. How or why the maximum current could have been reduced to 5 Amps I don't know.

In your first post you mention that setting the charge Voltage to 14.7 set of a fault. That is not a good sign.

One thing you can check is to bypass the charge controller completely and see how much current flows from the panels to the battery. If it is greater than 5 Amps then it looks like the controller is indeed faulty. If it is still only 5 Amps something is seriously wrong in the wiring or batteries themselves.

The batteries are new Trogen golf cart, 4 in series parallel. I will do the test you mentioned tomorrow. I assume I can throw the circuit breaker between the controller and batteries and then jump around it. Common is already connected.

I was getting the fault because I was not throwing the breaker before flipping the toggle switch. It is now set on 14.7v with no fault.

RobertR · December 2013

Re: Can't adequately charge batteries.

When I was doing the volt / amp checks today, I hooked the two motor home panels together, + to + and - to -. Then did short circuit amp test which was still 10 amps. Volts were of coarse still ~ 20v. I'm not an electrical engineer, I was a physics major, but should that not have doubled the amps to 20?

W = V * A. So if W doubles and V does not change A should double. It is as if putting two panels together added no additional watts.

With 20 v and 10 amp short circuit test that is 200w per panel out put. They are rated as 350w, but sun is low , not at a 90 degree angle, so 200w seems good. Putting 2 in parallel should be 400w . What am I missing?

Can't adequately charge batteries.

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