Battery Charging - Shore Power

[ianhef]

Hello everyone

Just wanted to thank you all for your contributions, all appreciated. Think I'll stick to using the wind generator and solar panels to charge the batteries. I'm kind of screwed as far as the laptop/internet go as they need 240V to run so looks like I'm going to have to plug in at times but I checked and have a special earth leakage 'electersafe' trip device in line so shouldn't be a problem.

Only worry now is that when I look around I see every boat has a power cable of some sort and I'd be pretty sure not all have proper onboard systems, as one of the posters asked above, is there anyway to check the dock is hot? (instead of waiting for a prop to drop off!)

[rover88]

My suggestion would be to purchase the parts and material to wire your boat for 110/220 properly. I went with the IOTA 45 amp charger (+-$250), but depending on your battery capacity you may get by with a smaller, less expensive, unit. The female three prong recepticle can easily be mounted in your cockpit and simply wired directly to the charger via a breaker. Check ebay or similar sites for bargains and even used components. Although a good portable charger and extension cord may serve your needs safely for now, the perception around most marinas is that these are big no-nos on a boat due to stray current. For a few hundred dollars you can avoid getting your new neighbors cross with you and have a proper, perminant solution that you can later expand.

[Boracay]

There is some good advice here, particularly about using an earth leakage unit. There are some portable ones available for a good price.

I've wired Boracay so the hull is insulated from the batteries most of the time by using a double master switch.

I'd suggest talking to your marina manager about what is acceptable, and also have a good look at how new and how good the marina wiring is. Australian electrical standards are high.

Most Australian boats don't appear to be wired for 230V AC as is common in American boats.

You could also ask your marina's electricity supply company about what is doable. While it's not done in America I've seen a few extension chords running to boats.

If buying a charger a decent double insulated marine one of more than a few amps may be a sound investment. Making sure that every item of equipment is double insulated is a must.

I don't think that staying on 12V power is practical while docked.

[ConradG]

Is your dc grounded to the metal boat? Hopefully not! Bonded? Hopefully not again! Somewhat contraversial subject but as far as your hull goes it isn't

Use the fancy grounf fault with a marine charger to charge and keep the a/c isolated from your boat! (Keep the dc isolated also as well as any dissimilar metals except your zincs just in case).

[chala]

Originally Posted by ianhef

Hi
1) Can I keep the batteries wired up to the services when charging or would I have to disconnect everything before charging?
2) Are there any problems with using this quick fix, temporary solution?
Hef

1) It depends on the battery charger. The main risk is to supply to the DC load a voltage higher than it can support. I will consider anything above 15 Vdc risky. Also if the DC load is bigger than the current the charger can supply then there is a risk of under-voltage (burn out, battery not getting charged). Find out by reading the documentation provided by the manufacturer if their charger suits your requirement.
2) This is not a quick fix. Most boats in a marina are connected to the shore supply by the use of plugable flexible cord (s) and very few are permanently connected to the shore by fixed wiring (requires the use of tools to disconnect). Australian Standard 3000 sets requirement for permanent wiring and AS 3004 did cover the wiring of electrical installations in marinas and pleasure craft at mains voltage. Due to the constant improvement of these standards, the use of licensed electricians, the fact that some requirements are more suitable to larger craft, make for the lack of popularity of 240 VAC permanent wiring in Australian boats. In Rome do like the Romans, in Australia do like the Australians and disregard other countries as most are stuck with electrical problems they have created.

Originally Posted by LiFeTech Energy

Speaking in my capacity as an electrical engineer and licensed electrical contractor/electrical supervisor there is no problem using an extension cord from the dock to power a battery charger for topping up your batteries so long as a few simple rules are followed.
1) Always use a power board with an ELCB (earth leakage circuit breaker). If there is any current leakage to earth the breaker will trip so you have protection.
2) All mains powered electrical appliances which are safe to use in Australia (as deemed safe by the state electrical authorities) will have a C-tick and electrical safety approval number marked on them. Only use appliances which have these marks.
3) Very few battery chargers made these days use the old traditional heavy transformers. They are all switch mode devices and if there is any leakage the ELCB will trip out.

I agree in general with the above, with the following recommendations: see if you can purchase a battery charger that is double insulated. A double insulated battery charger does not require earthing and for this reason does not have an earth pin, just two pins for the active and neutral and show the mark of a square inside an other square. An ELCB will protect you but not the boat. Most will trip at 30mA which is too much undesirable current leakage for the health of a boat. Beware of switch mode devices. Some are so poorly built that they require an earthing to bleed the RF away.

Originally Posted by ianhef

Only worry now is that when I look around I see every boat has a power cable of some sort and I'd be pretty sure not all have proper onboard systems, as one of the posters asked above, is there anyway to check the dock is hot? (instead of waiting for a prop to drop off!)

Quiet simple, minimize connection with the ground, do not be a path for other boat poor earthing. An anchor chain, a permanently connected fresh water hose can be a path and if you require the use of an earthed appliance, insulate it from the metallic part of the boat by the use of a suitable insulating material.

[LiFeTech Energy]

As a side note, as more and more electric boats are built and come online there will be greater demand for 240VAC supplied to these boats from the marina for regular charging of the propulsion batteries (such as the US made Duffy electric boat moored at Northbridge marina shown below).

This is sure to be a growing trend for those boat owners who are sick of diesel fuel and engine maintenance, fumes, noise and several other reasons.

[Dockhead]

Originally Posted by ianhef

Hello everyone

Just wanted to thank you all for your contributions, all appreciated. Think I'll stick to using the wind generator and solar panels to charge the batteries. I'm kind of screwed as far as the laptop/internet go as they need 240V to run so looks like I'm going to have to plug in at times but I checked and have a special earth leakage 'electersafe' trip device in line so shouldn't be a problem.

Only worry now is that when I look around I see every boat has a power cable of some sort and I'd be pretty sure not all have proper onboard systems, as one of the posters asked above, is there anyway to check the dock is hot? (instead of waiting for a prop to drop off!)

You shouldn't have any problem keeping a laptop going without shore power. Just buy a 12v adapter for it and run it off the batteries. The power consumption of most laptops is not so much as wind and solar can't keep up. I run my laptop off DC power, even though I have shore power, so that I can use it at anchor. It uses peak about 4 amps but averages less than 2, so the boat's DC system hardly notices it.

That being said, shore power is handy for lots of things, as someone said.

As to hot marina -- keep a good eye on your zincs. I wish I had. You can also detect any potential between your boat and and the water with a sensitive volt meter. Calder's book tells how. Good luck.


This was a just overhauled prop with brand new zincs before a few months in a hot marina: