Solar Questions, yes more solar questions

[KE6IRJ]

Okay, before you say it, I did search, and have been reading on this for days.

Here is my question.

I have a bonus coming possibly and am trying to decide if I want to use it for solar on our trailer. I intend to use the trailer mainly off the grid, and have fall hunting trip coming up for 7 days.
Currently, I have 2 GC2 batteries, plan to go to LED lights, and a propane heater other than the trailer heat.

So, in reading, I know I want an MPPT controller, remote monitor head, and probably 200-250 watts to keep my batteries charged for the week trip.

Is it better to shop around and piece together a system or stay with something put together by someone who knows?

I was thinking this one, because they are local to me and I have seen them in action on our last trip.
http://www.solar-electric.com/solar-panels-mounts-kits-accessories/prsy/rvandsmbasoc/rv-solar-kit-280-watts-mppt.html

I don't think I need an inverter right away, since I don't use other devices when camping right now. Do I need replace my built in power converter or is this all additional?

So, am I on the right track? Are there companies or brands to avoid? Better prices I have not found? Fill me in, what am I missing?

[pianotuna]

Hi,

The upside is you will have time to digest exactly what you need/want for solar, and that the price may well be lower.

Kudos on the led lighting and the tires.

KE6IRJ wrote:
Well, my expected bonus was not what was expected, so the LED upgrade and a few smaller needs as well as tires came first, so solar will have to wait.
😞

[KE6IRJ]

Well, my expected bonus was not what was expected, so the LED upgrade and a few smaller needs as well as tires came first, so solar will have to wait.
😞

[Almot]

KE6IRJ wrote:

Where do the breakers go in line?

Everywhere.
panels -> (Junction box?) ->#1 disconnect switch -> controller -> #2 breaker -> Pos bus -> battery fuse -> battery.

#1 can be switch or breaker in Baby Box, or skip the switch and use MC4 to disconnect on the roof.
#2 and Pos bus - in the Baby Box.

It is convenient to also add #3 - loads breaker, it also goes into Baby Box.

You can skip the Baby and have #2 and #3 as fuses - not breakers - less convenient.

Battery fuse will be on or near the battery.

KE6IRJ wrote:

I have settled on the Morningstar TS-45 for my controller. Most options I want for the price and highly rated.

...
What am I missing, beside marine grade wire, 4-gauge cable?

A lot of things are highly rated, doesn't mean you need them. I wouldn't trust Amazon ratings too much, average tech level is pretty low. 2*165W should be alright with 25A controller.

Not sure about marine grade cable - you are not installing this on the boat, are you? 🙂

4-gauge will be enough between 2*165W panels and controller, and overkill from controller to battery. Use Voltage drop calculator, max 2% drop.

[westend]

It's convenient to have a circuit breaker in series with the power wire from the modules. It allows to disconnect any solar power when working on the batteries or the rest of the 12V system. Some controllers always need the battery connections connected before the solar panel power wires if the module is producing power. If you don't interrupt the module power and disconnect the battery connection, good bye controller.

I use this one: CB manual breaker

[KE6IRJ]

scrubjaysnest wrote:
You won't get a better price on the Midnight Solar Big Baby Box and breakers then at NAWS, solar-electric.com. Two 150 watt, 12 volt panels run about $330 to $350 on ebay with free shipping.

Okay, stupid question but why do I need circuit breaker box?

I thought the solar panel connectors brought all the amps down on 2 wires, then to the controller, then to the battery. Where do the breakers go in line?

Panel 1 ---> Panel 2 ===> Converter ---> Battery


Due to size limitations on my roof, I am looking at 2 of the 165 Watt panels from Everbright

or 2 of the 100 Watt panels from Renology to start and I would have room for 1 more if desired later

I have settled on the Morningstar TS-45 for my controller. Most options I want for the price and highly rated.

***All can be found on Amazon, but I have the worst luck with links even using the dummy buttons. You know what they say, we will find a bigger dummy, and I am it.



So... talk to me. What am I missing, beside marine grade wire, 4-gauge cable?

[Almot]

pianotuna wrote:
Yes, it is a quality controller. It is intended for two battery banks, so it might be cheaper to have the plain jane sunsaver. Having the battery temperature sensor is a "must do".

I'm not sure it has adjustable voltage set points.

Ss Duo is 25A, single-bank SS is 20A max if I'm not mistaken. Setpoints on Duo can be custom-set, though this requires a laptop AND optional meter-bus adapter. Remote temp sensor is also optional - yes, very desirable to have. Remote display is extra. And all you'll get is 25A, i.e. 2*160W or 2*180W max.

With 2 panels I would think about Bogart Trimetric combo SC 2030 - TM 2030. 30A, ~$300 with everything adjustable including automatic Absorption adjustment and complete battery monitor.

Or - Xantrex/Trace 35A and 3*160W panels. Heck, my 490W fills AGM bank to ~93-95% before noon when it exits Absorption, and then it floats until sunset. As long as it doesn't rain. Don't need no battery monitor, muchas gracias.

[red31]

KE6IRJ wrote:


In order to give an accurate use on the remote display, the trailer power has to go through the perry's on the right, marked by a light bulb, right?

take a look at the brochure, page 2
load amp-hours is not available for that controller
http://support.morningstarcorp.com/wp-content/uploads/2014/07/RemoteMeterENG1.pdf

my non MS controller displays discharge KWH only if the load terminals are used. Typical tt user does not use the load terminals since loads can be more than the controller's rating.

[pianotuna]

No the light bulb indicates the ability to turn on and off a load. I.E. on at dusk off at dawn.

Yes, it is a quality controller. It is intended for two battery banks, so it might be cheaper to have the plain jane sunsaver. Having the battery temperature sensor is a "must do".

I'm not sure it has adjustable voltage set points.

[KE6IRJ]

Okay, typing and linking on my phone is difficult but let me try to clarify.

This controller is what I am referring to for reference.
Link

The solar panel wires go into the controller in the marked slots on the left.

The power to the batteries go out through the marked ports in the middle.

In order to give an accurate use on the remote display, the trailer power has to go through the perry's on the right, marked by a light bulb, right?

Is this a decent converter?

Edit, that one does not have the light bulb indicator, but I have seen it on others.

[JiminDenver]

Renogy may offer some controllers but they are just rebadged controllers that can be had on ebay for less without their label. In some cases the regranded version is last years while a mewer model is available. It happens with windynation and Eco-w too, Eco-w may make some controllers themselves but they rebrand others.

[Almot]

KE6IRJ wrote:
Still looking, but I really like the controller having the remote display so I can see what's happening without opening my storage compartment.

It looks like to do this, I have to run all the power through the controller, not just the power to the batteries.

Still looking. How is everyone's personal experience with Renology? I see a lot of reviews mentioning fire and melting.

#1: Remote display is convenient. $12 Voltmeter will show what's happening with battery charge - this is important. Expensive - and rather basic - remote meter of Xantrex, and similarly basic meter of few other controllers will show this, and also charging current - more fun than usefulness :). Seriously though, I would pay premium for a remote if I needed it (my controller is inside the rig, with onboard display).

#2: I don't understand. You always run "all the power" to battery through the controller. This is what controller does - regulates voltage coming through. Remote meter is connected via network plug and telephone style cable, there is no "power" there. Like I said, it will only show current to the battery, battery voltage and daily solar harvest. Which is not too bad.
A separate "battery monitor" would provide more data and would cost a lot more, you may or may not need it. There is one PWM that does this all - Trimetric SC 2030 - it's an add-on to their battery monitor TM 2030 rather than a standalone PWM, and it's 30A, not 35.

#3: No personal experience with their controllers. From what I see, Xantrex, Morningstar and few other guys will kick Ren's ars with hands tied behind the back. Don't remember if Renogy make 35A or 40A PWM, and 30 won't be enough for 3*160W.

[pianotuna]

Hi KE6,

Do you mean the solar harvest, or do you mean some sort of amp-hour counter that monitors total energy use in the rv?

I have the controller on the wall. I rarely look at it now.

[KE6IRJ]

Still looking, but I really like the controller having the remote display so I can see what's happening without opening my storage compartment.

It looks like to do this, I have to run all the power through the controller, not just the power to the batteries.

Still looking. How is everyone's personal experience with Renology? I see a lot of reviews mentioning fire and melting.

[CJW8]

pianotuna wrote:
Hi CJW8,

Which MPPT controller will you use? I hope it has a temperature sensor.

Here is one possibility

Temp sensor is $10 extra. With this he has room to grow, and he can series them up for smaller wire.