PV For RV (5th Wheel)

System

I cueently have the following system.

4 - 80W Panels

1 - Specialty Concepts SC-15 Controller

4 - Trojan T-105RE Batteries

I need to replace the Specialty Concepts SC-15 1997 circa controller with a more modern controller.

I will also be adding TriMetric 2025 w/500A Shunt.

Due to the low voltage of my panels I don't see the benefit for using an MPPT controller. I am leaning towards the Morningstar TS-45 with the remote.

I am concerened that maybe this controller is "overkill" for my particular system.

Any input or recommendations please feel frr to chime in.


Johnny

mike95490

Re: PV For RV (5th Wheel)

Why do you think you need a new controller ? The TS45 is a lot of overkill, and may not be any better than what you already have. 320W is not an awful lot of power (21 amps)
What is the Vmax power spec on your panels ?

System2

Re: PV For RV (5th Wheel)

17 volts at load

4.7 amps at load

Why a new controller?

The needle that points to yellow - red - green is hard to read and the needle
for the battery portion does not work ie. it does not move at all.

Plus I have no way of knowing what the voltage is set at on this controller.
I want to be sure I can set it at 14.8 volts per Trojan's data.


Johnny

mike95490

Re: PV For RV (5th Wheel)

Well, the MS TS 45 PWM is a decent controller. It should work fine, as all the other ones at http://store.solar-electric.com/chco.html (Our host's store) as long as you are within the capabilities of the controller.

The prostar 30 has a meter internal, but maybe you want the remote on the 45.

dgsloan

Re: PV For RV (5th Wheel)

I have 80w panels on my RV x 8. What I bought is four grid tie inverters at 100 dollars each and use one for each pair of panels. This way I do not have to switch anything. When I am at a site without plugs I turn on a pure sine wave inverter (800w) and the panels sync into this power so that the inverter only has to work when the sun goes behind the clouds. The inverter will peak out at about 1000 watts which sometimes happens when the air conditioner kicks in. Some of the sites that I visit have pretty poor power so it is nice when the fridge stays on electrical without burning any plugins. The pure sine wave inverters are the best if you have a microwave.

System2

Re: PV For RV (5th Wheel)

Can you explain "grid tie iverters" and where one would purchase such an item.
You are the first RV'er I have heard of using such a thing. I have a 2400 watt Trace inverter in my rig and use an autoformer to plug into to peotect from voltage issues at the electrical poc.

dgsloan

Re: PV For RV (5th Wheel)

Johnnycb wrote: »

Can you explain "grid tie iverters" and where one would purchase such an item.
You are the first RV'er I have heard of using such a thing. I have a 2400 watt Trace inverter in my rig and use an autoformer to plug into to peotect from voltage issues at the electrical poc.

Grid Tie Inverters have been used for years on houses because the battery bank is the grid. When you over produce electricity the power goes back into the grid. With a grid tie inverter the box hooks through a breaker to the solar cells on the one side and 120 volt AC on the otherside. It runs off a microprocessor that senses the AC power and determines how to inject the power into the already present AC power. This is similar to raising the voltage to charge a battery. In AC the Frequency is the adding method instead of voltage. When an air conditioner is turned on the load reduces the frequency and when the frequency drops enough the power company adds generation to bring it back to 60.00 cycles.
Past grid tie inverters were large boxes where solar panels were tied in series to produce dangerously high DC voltages which were then converted to AC. Newer micro inverters are smaller boxes tied to each panel or pair of panels and produce the AC right at the panel. Since solar panels can get quite hot, some of these inverters are made to withstand quite a bit of heat - sort of like the capacitive discharge on an old 69 Evenrude outboard which have lasted for years. Other micro inverters are made to be mounted fairly close to the panels but where they can run at a normal temperature.
A lot of these more portable converters are made in China and the quality is getting to the point where they are usable in portable applications such as trailers. Although some of these devices are rated at 300w with 600w peak it is much safer and more efficient to run them at half the rated power. Besides which it is hard to find a pair of panels that fit on a trailer and go over a hundred watts! If you go to EBay and search for Grid Tie Inverters these devices will show and ones such as Power Jack (which have been going for years) are priced delivered at 100 dollars.
Make sure that you also buy a set of marine breaker panels and a fuse panel with fuses rated to the solar panel rate. It is also a good idea to add a MOV across the plus and minus between the fuse and breaker to protect against back voltage such as lightning.