Do I need a new solar controller?

[Kalimniosjohn]

My girlfriend and I have recently (finally) moved aboard our boat. My solar controller, a tri star 45, doesn’t seem to be doing it’s job properly. Granted the batteries are being charged somewhat, but definitely not to 100%.

The parameters set are 14.6 absorption charge and 13.4 float charge. I never see these numbers though. The max I have ever seen in the 5 days living aboard is 13.1 and a maximum of 105 watts being used. I have two 240 watt Samsung panels. Also it constantly reads a temp of 170. I can’t find anything even close to that hot around the controller or batteries. What gives?

I need help to not kill my batteries. All AGM group 31s. 6 in total. One is a starting battery, 3 house batteries, and two up forward to run the windlass and freshwater toilet supply pump. I have yet to determine if the two forward and the three midship are all working together or separately.

They will be maintaining at 13.1v and as soon as the sun goes down they drop very quickly to around 12.4-12.5 and go down fast from there.

Are my batteries shot? Is my controller shot? What do I do next?

As always thanks much in advance!

[Kalimniosjohn]

Also we are not using a crazy amount of electricity. We’ve been being very careful to limit amps used until this is sorted. Today so far we’re just over 44 amp hours since 0700 this morning, and that’s including the refrigerator.

[motion30]

Unless your batteries are extremely low eventually you should see your absorption voltage 14.6. Can you charge them with a Shore power or a generator and see what happens

[smac999]

that ah is probably what the solar controller has produced. it has no way of knowing how much the boat used. you need a battery monitor like a victron 700 for that.

most likly it is only charging the house. you'll have to see how the windlass and engine batteries are all wired. you may have something like an acr or echo charger.

if you are charging to 13.1v you are likly in bulk and the batteries are very low. and the panels are not getting them charged proof by them being 12.4 as soon as the sun goes down. so they are never getting above 70% or so.

if you are only getting 90w from your 480w panels that is also a big problem.

you need to look over the whole system. measure amps from each panel separate and see if both are producing. measure the voltage of the panels themselves. what are the ratings of those panels? a 240w is probably a high voltage? and that is a pwm controller? which may not be a good match.

you really need to find a dock and get them fully charged and see how they behave. and before you destroy them even worse. what battery voltage are you getting first thing in morning before the sun comes up?

[Kalimniosjohn]

Oh ha they are Bosch not Samsung. At any rate this is the plate on the back. Looks like 37 volts..?

I just got a 3000w portable generator but it’s not up and running yet. I ordered the adapter to plug strait into my 30amp shore power inlet. Should have it in a couple days.

We are living in the mooring field just south of peanut island in west palm, so no shore power for us.

And generally the batteries are reading 12.1-12.2 first thing in the morning.

[smac999]

if you are running a 30v panel through a pwm controller I think that is really bad. it should be like 16-18v. you really need a mppt one. that might be why it's so hot too.

how big is your battery charger? if it's a small charger you are just wasting genny fuel.

[Kalimniosjohn]

The charger is a ProSine 2.0 2000 watt inverter charger by xantrex.

It isn’t getting hot either, not even warm actually.

[Captain Bill]

The TriStar 45 is not an mppt controller and as Smac999 said you cannot get the rated wattage out of a 37volt panel charging a 12v battery unless you are using an MPPT controller. The numbers you are reporting as usage are actually what you are producing, not what you are using. I have a TriStar 60 MPPT so I know what I'm seeing. Even if you were producing the ISC amperage at 12.5 volts, which your panels won't do, you would only be producing about 100 watts per panel. In the real world you would be lucky to produce half of that which is about what you are showing us. You definitely need an MPPT controller. I know the price of the TriStar MPPT is much higher that the PWM TriStar, but there are many other MPPT options out there. Did someone recommend that you buy this configuration or did you choose it yourself?

[Compass790]

As smac999 says you need to measure the panels output & the output after the controller. Do you have a clampmeter? Check ALL your connections between panels/controller & batteries for a start.Often it's something simple like that.
You sure will wreck your batterys in short order with that charge/discharge profile.

[sailorchic34]

the Morningstar TriStar 45 is a pwm solar charge controller designed for either a 12-volt or 24 volt system. You have 24 volt panels but 12 volt batteries. So yes you're charge controller is not correct for the panels. I would recommend a victron smartsolar mppt 100/50. you can download an app to your phone or tablet and keep track of the output that way. It's quite a good charge controller.

[Kalimniosjohn]

Originally Posted by Captain Bill

The TriStar 45 is not an mppt controller and as Smac999 said you cannot get the rated wattage out of a 37volt panel charging a 12v battery unless you are using an MPPT controller. The numbers you are reporting as usage are actually what you are producing, not what you are using. I have a TriStar 60 MPPT so I know what I'm seeing. Even if you were producing the ISC amperage at 12.5 volts, which your panels won't do, you would only be producing about 100 watts per panel. In the real world you would be lucky to produce half of that which is about what you are showing us. You definitely need an MPPT controller. I know the price of the TriStar MPPT is much higher that the PWM TriStar, but there are many other MPPT options out there. Did someone recommend that you buy this configuration or did you choose it yourself?

This entire solar system was on the boat when I bought it. I have been so busy fixing and rebuilding everything else I just kind of hoped it would all work. Alas, there will be nothing that just WORKS, and I will have to start researching solar next.

I don’t mind shelling out for a quality solar controller. I just want to make sure I get the right one. I plan on eventually adding 200-300 more watts of solar so if there is a controller that can handle all that juice that’s the one I’ll get. Or just get two smaller quality ones.

[Captain Bill]

I forgot to address the issue of the temperature reading. I assume you purchased the optional temperature sensor. If you did not and have the temperature sensor switch set as having one versus not having one, it would create a spurious reading. This would cause the controller to cut back on its power output to prevent damaging the batteries. This would make your power production even worse than if just running the PWM controller.

[Captain Bill]

Originally Posted by Kalimniosjohn

This entire solar system was on the boat when I bought it. I have been so busy fixing and rebuilding everything else I just kind of hoped it would all work. Alas, there will be nothing that just WORKS, and I will have to start researching solar next.

I don’t mind shelling out for a quality solar controller. I just want to make sure I get the right one. I plan on eventually adding 200-300 more watts of solar so if there is a controller that can handle all that juice that’s the one I’ll get. Or just get two smaller quality ones.

What kind of shading issues do you have on your panels? If they are on an arch and don't really have a shading problem most of the day a single controller will do. If you have shading issues on one panel at a time then two smaller controllers are better. I have two 320 watt panels running through a TriStar 60 MPPT controller and I end up throwing away most of the power they produce between March and September, not so much in the Winter half of the year. Emarine systems in Ft Lauderdale is a Tristar dealer. You might ask them if they'll give you a trade in on your old controller for an MPPT, if not there are a lot of MPPT controllers out there for less money.

[Kalimniosjohn]

The panels share a arch with a wind generator. I suppose the one panel could get some partial shading.

[Captain Bill]

Originally Posted by Kalimniosjohn

The panels share a arch with a wind generator. I suppose the one panel could get some partial shading.

It looks like you won't have a shading problem when the boat is pointed north, but a bit of one when the boat is pointed south or east. If you are south of Peanut Island in WPB then the tide is probably controlling which way you are pointing and that will usually be pretty much north or south. It's probably not a terrible problem in the summer, but may limit your power gain in the winter,at least when the tide is going out during the middle of the day.