Shore Power
We have 200w of solar, which generally keeps everything running. And I
do like not having to think about the hazards of 110v AC. So, for most boats our size, I'd advise sticking with just solar.
This is really more forward-looking - to the days when there will be just two of us cruising together. Don't get me wrong - we love sailing with our kids. But it won't be too many more years before our cruising schedule won't be limited by the school calendar, so we'll be out when it gets a little colder. Thus, a little heat might be nice. We bought a
small 12v heater (Caframo markets it as a defroster, but in a little C-22 cabin, 100w warms things up quickly). At ~8A, we could run it for an hour or two per day on batteries. But our solar wouldn't keep up indefinitely, so we'd want to be able to recharge when we get back to power. I suppose we might someday add a real (vented) propane heater, but that's not in the cards anytime soon.
And - for days on the other end of the heat scale - we have our
Alpicool freezer. Thus, we looked into 'real' shore power. That and the fact that I'm a geek and like playing in my shop...
So on to the actual system:
I found a Blue Sea 8027 panel on eBay (new) for $120, and a used ProMariner FS30 fail-safe galvanic isolator for $90 (
@Maine Sail details
how to test a galvanic isolator, and this one checks out good).
I mounted the panel in a sturdy plastic enclosure, with a little FRP reinforcement on the interior where the panel screws in. I learned a lot more after the initial panel purchase, and I ended up replacing the main breaker with an ELCI version (from here at the SBO shop; as always, they were really helpful!). In retrospect, it might have been cheaper to buy an ELCI panel up front; live and learn.
I used a Marinco EEL cordset (a little better than their economy version) and replaced the boat end with a SmartPlug end. I originally used a 25-foot cordset, thinking that should be plenty for a 22-foot boat. But no, it turns out some marina pedestals are a fair distance from the bow, so I replaced with a 50-footer this winter.
I decided to buy the Marinco over SmartPlug's own cord because I wanted the female end as well to make a pigtail for use in my shop (I could have bought a shore-power style outlet for my shop, but that would cost more and seemed overkill).
I elected to install the SmartPlug inlet in the port-side cockpit pocket, planning to route the shore power cord over the coaming near the bulkhead and underneath the cockpit cushion back to the inlet. Hopefully that will avoid tripping hazards, and it keeps everything out of the way. That required a bit of 1/8" fiberglass epoxied in place, to create a level surface for the mount.
I wired a single hospital-grade GFCI, mounted in an exterior electrical box next to the panel (I may chain another outlet or two off this GFCI eventually, as we figure out where they'd be useful). I wired those connections with heat-shrink fork connectors (the screws are captive, so you can't use a ring connector).
Don Casey says that you can use stranded wire in the clamp-style outlets (commercial-grade screw-tightened clamps - not the spring-loaded connections I don't even trust for home wiring). But a crimp connector seemed more familiar to me, so I picked up a package of forks.
That was the entire system the first year, and it went essentially unused. Last year, I added a Sterling ProCharge Ultra battery charger (trying to spread out the boat bucks just a bit). I bought it from
@Maine Sail (when his store was still open), and selected a 40A charger based on the following logic:
- We currently have 2x 105Ah Lifeline AGMs, for a total (new) capacity of 210 Ah. @Maine Sail quotes Lifeline as saying .2C is the minimum. That would be at least 40A of charging capacity. That recommendation might be more applicable to sizing an inboard's alternator, in an effort to get the batteries back up close to 100% with relatively short engine runs, but I went with it anyway.
- When it's time to replace the AGMs, we might go for LifePO4s, which would also like plenty of charge current.
- When plugging into shore power, we'll almost always have 8+ hours of charge time. Including the freezer, lights and laptop charging, we might pull as much as 5-6A while plugged in. So at 50% discharge, a 20A charger should bring us back to ~80% in ~4-5 hours, with another ~3 in absorb. Fine, but not a lot of headroom. The 40A was only $76 more than the 20A, and the connections are real 1/4" lugs instead of the screw clamps on the smaller models.
A couple pictures of the back side of the panel - one of the original installation, and another with the voltmeter and charger wiring. The jumper block in the latter one is 12v, for panel LEDs, etc.
The only other change I made is a flip cover on the AC panel (which you can see in a couple of the most recent pictures). The panel seemed well protected in the coffin, but we realized once last year that shoving a duffel back into the coffin had flipped the master breaker and turned the charger off overnight. That was a pretty easy fix; tapped mounting holes directly in the aluminum panel and screwed it on.
The system is working great. No complaints thus far.
Time: 19.75 hours
Cost: ~$1050
- Marinco EEL 50-foot cordset: $100
- SmartPlug Inlet: $46 (Amazon return)
- SmartPlug retrofit connector: $75 (Amazon)
- Blue Sea 8027 AC Panel: $120 (eBay, new old stock)
- ELCI Breaker: $125 (SBO)
- Electrical box for AC panel: $28 (Amazon)
- ProMariner FS30 Galvanic Isolator: $90 (eBay, used)
- (I couldn't justify a $1k+ isolation transformer for a system of this size
- Hospital grade GFCI Outlet: $20 (Amazon)
- Wire and fork connectors: ~$30 (GenuineDealz)
- Charger: ~$360 w/shipping (marinehowto.com)
- Digital Voltmeter (mounted in AC panel box): $15 (Amazon)
- Ground bus: $20
- Flip cover: $15
- I already had other assorted connectors, some scraps of #6 cable, and #6 lugs
PS - Now that I have a 50' cordset, I plan to reassemble the shorter one, making an extension cable of ~23'. When my order for yellow heat-shrink tubing arrives, I will crimp it together (with good crimps). PM me if you're interested.