Universal Voltage Battery Charger – Shore Power Setup

[Donahue]

I’m upgrading my boat’s electrical system, including replacing the old Heart/Freedom inverter – charger. Instead of going with a Victron multiplus, I’m considering eliminating any pass through AC circuits and just installing a battery charger. The shore power circuit would be wired to the charger and nothing else; I’d have a separate inverter for the limited on board AC loads. I’m getting rid of an old generator, air conditioner, and AC driven fridge.

One benefit of this setup would be that some Victron chargers can operate on a wide range of AC voltages and frequencies so I could plug into shore power anywhere with the right adapter. The other benefit would be reducing or eliminating stray current corrosion issues.

Has anyone wired their boat like this? The only downsides I see are having to buy and install a charger and an inverter and being limited by the size of your batteries and inverter in terms of the onboard AC loads that you can power.

Thanks.

[PippaB]

You’re describing my favorite setup for a boat used across multiple electrical grids. We had a European built boat that we set up exactly the same way and did not really care what voltage or frequency was on the dock.

A fully-isolated battery charger as the only shore power consumer removes a lot of the potential complexity of shore power systems

[Bowdrie]

Originally Posted by Donahue

Has anyone wired their boat like this?

Sure enough, I've long been a proponent of separate/discrete devices for inverting and charging.
Takes a bit more space but sure simplifies things, it's a win-win.

[Pete7]

Same here. We do have a manufacturers installed consumer unit and 4 plug circuit in the yacht but rarely use it unless we want to top up the domestic bank using a 40A Sterling battery charger. Nearly all our annual power needs are met by solar or the alternator. A 2kW inverter supplies sufficient power to run everything apart from the hoover, which is on the to do list by replacing with a battery Dyson.

We did notice the anodes last longer because we don't plug in to shore power very often. There are some losses going 12v to 240v, but in the grand scheme of things not worth worrying about.

Pete

[coopec43]

Would one of these have any relevance?

https://www.amazon.com.au/C7-Intelli...d&gad_source=1

[Donahue]

Thanks All! Much appreciated.

[SweareDeep]

I'm currently getting my 120V/60Hz boat ready for 230V/50Hz, and will be feeding 230V/60Hz into a Victron Skylla-IP65 (1+1): it takes 90-265V at 45-65Hz and outputs nominal 12V / 70A.

[Donahue]

Originally Posted by SweareDeep

I'm currently getting my 120V/60Hz boat ready for 230V/50Hz, and will be feeding 230V/60Hz into a Victron Skylla-IP65 (1+1): it takes 90-265V at 45-65Hz and outputs nominal 12V / 70A.

I think I'm going with the same charger. I was also considering the slightly smaller Victron IP 43 that accepts similar input voltage and frequency but has a smaller footprint.

Do you plan on keeping a galvanic isolator? I think that it's unnecessary because shore power is only connected to the battery charger and not the ship's ground. My plan is shorepower outlet, isolated double pole breaker, charger. All onboard AC circuits are connected to the inverter only on a panel separate from the shorepower breaker.

[SweareDeep]

I think that charger has a case ground, which would go to ship's ground. However, the incoming AC ground should be isolated from the case.

[boatpoker]

Originally Posted by Donahue

The other benefit would be reducing or eliminating stray current corrosion issues.

How does that eliminate potential stray current corrosion issues ?

[Donahue]

Originally Posted by boatpoker

How does that eliminate potential stray current corrosion issues ?

Because the shorepower circuit is not grounded to the boat like a typical setup, isolating the boat's ac and dc circuits and blocking any low voltage stray dc current that tries to sneak aboard. The battery charger is essentially an isolation transformer. I'm not sure if this technically complies with ABYC.

[boatpoker]

Originally Posted by Donahue

Because the shorepower circuit is not grounded to the boat like a typical setup, isolating the boat's ac and dc circuits and blocking any low voltage stray dc current that tries to sneak aboard. The battery charger is essentially an isolation transformer. I'm not sure if this technically complies with ABYC.

Shore power is irrelevant to stray current corrosion. Stray current is a DC process. Don't you have 12v bilge pumps or any other DC conductors in the boat ?

I've done hundreds of stray current corrosion surveys and have yet to see one caused by a shorepower connection ... galvanic corrosion yes but not stray current corrosion. For some unscientific reason almost every person suffering from stray current corrosion blames neighboring boats and the "hot marina" while their own boat was the cause in every case I've seen.