I'd pput that new car battery in your car, use the old car battery as a backup in the boat and buy a new deep cycle as the primary battery. You will need a dual or two separate solar charge controllers as the batteries will have different charge characteristics, capacities, age.
When I read that suggestion I wondered what diagram the proper sequence and connections for all those batteries and chargers would look like. Maybe it's just me but it seems I often get into long discussions that begin with well you should'a.
Recommend a 100 watt Solar Setup for my C-22
- Thread starter Carl Wonderful
- Start date
I've done it before with two separate solar charge controllers. Everything shared a common ground. You obviously shouldn't select 1+2 on your battery selector (with two different batteries) unless you have an inboard and are in a bind. The OP is going to have an outboard with pull start on a C22
Deep cycle batteries properly cared for and SIZED PROPERLY for the daily load and ercharging capabilities can and do last longer than 8 years.
It is important to recognize the USE CASE in the OP's post: he has a Catalina 22. I used to own one great boats. But suggesting that this boat needs multiple batteries and solar controllers is, imho, overkill. Let's not impose inboard engine driven larger boat best practices on an outboard powered small boat with meagre daily loads.
It is important to recognize the USE CASE in the OP's post: he has a Catalina 22. I used to own one great boats. But suggesting that this boat needs multiple batteries and solar controllers is, imho, overkill. Let's not impose inboard engine driven larger boat best practices on an outboard powered small boat with meagre daily loads.
Here are the applicable examples:When I read that suggestion I wondered what diagram the proper sequence and connections for all those batteries and chargers would look like. Maybe it's just me but it seems I often get into long discussions that begin with well you should'a.
Basic Battery Wiring Diagrams This is a very good basic primer for boat system wiring: Basic Battery Wiring Diagrams
This is another very good basic primer for boat system wiring: The 1-2-B Switch by Maine Sail (brings together a lot of what this subject is all about)
http://forums.catalina.sailboatowners.com/showthread.php?t=137615
This is a newer primer for boat system wiring design with a thorough diagram: Building a Good Foundation (October 2016)
Building a DC Electrical Foundation
The Short Version of the 1-2-B Switch Stuff: Electrical Systems 101 This is a link to the Electrical Systems 101 Topic, reply #2
Morningstar does seem like the way to go.
Can someone explain why someone would choose a 10A or a 20A? (not understanding this..)
I am in PA so a lot of half sunny days here. I was thinking a 100 watt panal because even though we do not have a fridge, I do like to have a lot of unique lighting options around the boat and I also intend to play and record some music on the boat so I will need a bit of power for my little pedalboard and travel recorder and things like that. I plan to spend up to 4 days on the boat at a time (boat camping).
Thanks!!
Can someone explain why someone would choose a 10A or a 20A? (not understanding this..)
I am in PA so a lot of half sunny days here. I was thinking a 100 watt panal because even though we do not have a fridge, I do like to have a lot of unique lighting options around the boat and I also intend to play and record some music on the boat so I will need a bit of power for my little pedalboard and travel recorder and things like that. I plan to spend up to 4 days on the boat at a time (boat camping).
Thanks!!
Also can I expand to 2 batteries down the road with any of these controllers... or is that a whole other complication?
Try to add up how much power you think you’ll consume between the lights and the electronics to figure out how much you’ll need to put back in through solar. The 100 watt panel could be expected to put about 30-40 amp hours back in per day. Once you know the solar panel size you can size the controller. If you stay with 100 watts you’ll probably be ok with a 10A controller - 100 watts is a bit under 10A at 12V. If you went up above 150 watts or so the 20A would probably be better. The other spec to pay attention to on solar controllers is the maximum voltage. You need to ensure the controller’s max voltage is above the Open Circuit voltage of the panels (plus some percent if the panels will be used in the cold). If the controller’s amperage rating is too low you’ll lose some efficiency. If its voltage rating is too low you can fry the controller entirely. I think Victron has a calculator that will recommend the best controller based on panel specs; not sure if Morningstar has anything similar. Whether it’s charging one battery or two doesn’t really matter from the standpoint of the controller.
OK, @Davidasailor26 pretty much covered the solar controller. I'll only add a Victron 75/15 would be a good choice. It can handle up to 75v and 15a. That gives a little leeway on the 100 w panel.
Chargers should be sized based on the amphour (ah) capacity of the battery bank being charged. It is expressed as a percentage of the battery's capacity. A 1C charger will produce 100% of the battery's capacity, for a 100ah battery that would be 100a. Few batteries are happy being charged at that rate. LA batteries generally are happiest at .1C (10% of capacity) to .2C (20% of capacity).
So, the first step is to determine the capacity of the battery bank. The capacity of a Group 31 battery is around 100ah. A properly sized charger would be either a 10 or 20 amp charger. There are 2 advantages to going with the larger charger, it allows for adding an additional battery and recharging will be a little faster.
The charger should be a 3-stage charger with Bulk, Absorption, and Float stages. Ideally and for future proofing the voltages for each of those stages should be customizable. Some chargers will be advertised as a 20a two battery (or three battery charger). It is important to note the charger splits the charge current between the batteries attached to it, thus a 20a charger with 2 batteries will provide 10a to each battery or 20a to a single battery connected to the charger.
For your use a 20a charger should be adequate and a good choice would be a Victron charger. There are cheaper chargers on the market, however, Victron is a reliable company that builds good products. Companies like Renogy and Noco receive mixed reviews with the negative reviews being pretty strong. Sterling and ProMariner are also good brands, some of the chargers are the same, just different labels.
I ran 6A charge controllers with a 100w panel for 2-3 years without issues but that is pretty close or possibly over the limit depending on who you trust. My controllers were PWM and I never had to worry about my batteries being low
The Morningstar Sunsaver Duo w/display I recommended can support two batteries. $104 before taxes and it includes a display. I picked one up but haven't had a chance to install it
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FWIW I have used a Sunsaver Duo for the last eight plus years and it has worked well for me. While maybe not the very most efficient controller out there it has been worth my money.
MorningStar seems to be focused on reliability over fancy features. A lot of their products are made to be deployed to remote desert environments