Archive for the ‘Corrosion’ Category

Marine electrical questions?

June 28th, 2010 by Kevin Hannula and Nick Kroes

Marine Ac/Dc attempts to answer your questions about boat wiring and marine electrical techniques, concepts, and products. We get lots of mail from folks in mid-project or who are just curious about their boat’s electrical setup.

There are loads of post already on the site which we hope you will browse through. If you’re trying to track down info about a more specific category, please use the search box in the upper right of this page or check out the list of various subjects farther down on this page.

If you aren’t able to find the info that you need to complete your particular boat wiring project, please send us an email at boatwiring@gmail.com.

Thank you for visiting. We look forward to hearing from you and hope that you will be able to come back often.

Posted in Battery Charger, Battery Switch, Boat Wiring, Bow Thruster, Circuit Protection, Corrosion, Cruisers, Gauge Panels, Harnesses, Marine Electrical, Navigation Lights, Pontoons, Runabouts, Signaling Devices, Switch Panels, Testing, Trolling Motors, Uncategorized, VSR, Wipers | Comments Off

Boat harness = Beetle harness?

August 11th, 2010 by Kevin Hannula and Nick Kroes

Kevin,

I have been thinking about corrosion, road salt and +/- ground systems in relation to rust and basic electrolysis. It is interesting that marine electrical has already addressed these kind of issues.

So, would it be possible to build a custom wiring harness for a VW Beetle that would bypass the body ground a’la boat wiring?

Thanks,Malcolm Buchanan crossing Irish Sea

Scott

Hi Scott,

Boat wiring harnesses avoid body grounds for two reasons:

  1. To minimize galvanic corrosion
  2. Most boats are not made completely from conductive metal

If you built a harness for your Beetle, you could certainly run individual grounds back to a ground bus instead of using the car body/frame. It would nearly double the amount of wire required for your project, but you would potentially eliminate electrical circuit problems caused by corrosion.

Kevin

Posted in Boat Wiring, Corrosion, Cruisers, Harnesses, Marine Electrical, Runabouts | Comments Off

Ac/Dc connection

July 12th, 2010 by Kevin Hannula and Nick Kroes

Kevin,

Why are ac and dc ground buses tied together in boat wiring? It would seem to be a possible source of electrolysis.

George

Hi George,

You are correct.

When you tie the AC and DC ground buses together, you definitely create the path for stray current corrosion through your shore power connection.

BUT

The wire provides a ground path in the event of an AC fault to the DC system in your boat wiring. Without it, your AC breaker will not trip. The path to ground would be through the boat’s DC system, through the engine, and through the water. There is too much resistance in the water to cause the breaker to trip. All DC devices would become energized at 115V AC.

It is probably better to corrode a drive than kill a friend. I always recommend keeping the ground buses tied together. So does the US Coast Guard and the American Boat and Yacht Council.

Kevin

Posted in AC Wiring, Boat Wiring, Circuit Protection, Corrosion, Cruisers, Marine Electrical, Shore Power | Comments Off

12 Volt Accessories – 24 Volt System

May 17th, 2010 by Kevin Hannula and Nick Kroes

Kevin,

On my boat wiring, I have a 12 volt battery for starting my motor and a 24 volt house battery setup for running my trolling motor and accessories.EzAcDc offers Smart Battery Switch Systems to make your boat wiring project easy.

I would like to have my electronics, which are all 12 volt except for the trolling motor, run off my house batteries, and use my starting battery for starting the engine only.

The boat manufacturer had the house batteries rigged up in 24 volt, but has the accessories connected in 12-volts across only one of the house batteries. Although this works, one of my batteries drains well before the other. Also, something tells me that boat wiring like this might not be a good idea.

Is there a better way to do this? Should I try to balance the load across both house batteries, or should I use a DC/DC converter to step down the 24 volts to 12 volts in order to run the accessories properly? Also, can I use a Smart Battery Switch VSR to charge my 24 volt system from my motor once the starting battery is charged up?

Thanks,

Scott

Hi Scott,

Your boat wiring  has been engineered in a safe, conservative way.

You run into potential problems when you start running two, separate, 12 volts systems with their grounds 12 volts apart.

  1. Stray current corrosion.

    The engine is connected to one battery ground, while the hull is connected to second battery ground – engine corrodes away to protect hull

  2. Fires caused by crossing grounds.

    Gauges and navigation lights have same ground to complete circuit. Your engine harness grounds the gauges and your boat harness grounds the navigation lights. If you connect the engine ground to battery 1 ground and the boat accessory harness to battery 2 ground, the 24 volt jumper wire for your trolling motor completes the dead short from Battery 1 positive to Battery 2 negative.

    The short circuit path is the Accessory harness ground which is connected to battery 2 negative (battery 1 positive), to navigation light switch ground, to gauge ground, to engine harness ground, and back battery 1 ground.

    There is no circuit protection in this circuit so the smallest wire burns. This is usually the small ground jumper wire that connects your gauges.

If you are going to separate circuits to both batteries, install circuit protection in both the negative and positive wires and pay close attention. Label all battery connections because swapping a ground at the battery will cause a fire.

Best of luck,

Kevin

Posted in Boat Wiring, Circuit Protection, Corrosion, Cruisers, Navigation Lights, Pontoons, Runabouts | Comments Off

Marine Grade or Regular Wire?

March 7th, 2010 by Kevin Hannula and Nick Kroes

“Can I use ‘regular wire’ for my boat wiring?” The answer to this common question is a qualified “yes,” if the wire is SAE (Society of Automotive Engineering) J378, J1127 or J1128. These wires are designed for “surface vehicles,” not for the special requirements of the marine electrical industry, but meet the minimum standards for boats in limited circumstances. Even if tinned copper, they should not be run in bilge spaces or other areas subject to moisture from spray or dripping. They should not be run in engines spaces, unless marked “oil resistant” and “75°C”. They should not be used in applications where subjected to vibration or frequent flexing and must never be used for 110 volt applications. For safety, use only wire which is marked with size and type.

Most importantly, SAE wire is up to 12% smaller than AWG Boat Cable which means that, in many applications, larger gauge wire must be used to stay within the voltage drop limits recommended by experts (see Tables C & D). The wire charts found in “Chapman’s Piloting” and other publications are all for “AWG” wire like ANCOR, not “SAE” type wire.

Using the wrong type of boat wiring can cost you more in the long run. Insist on Marine Grade™ Boat Cable by ANCOR. It is UL approved for the corrosive marine environment and charter boat service. Marine Grade™ Boat Cable is specially designed to exceed all test standards for cold bend, moisture and oil resistance, heat shock and flammability. This ensures the safest, easiest to install, longest lasting and ultimately the least expensive electrical system you can buy. Only ANCOR offers a complete line of Marine Grade™ Boat Cable for every need.

Posted in Boat Wiring, Corrosion, Harnesses | Comments Off

Boat wiring resource for boat owners

August 27th, 2008 by Kevin Hannula and Nick Kroes

Everyone at Marine Ac/Dc is very excited about the recent launch of EzAcDc. These guys could easily become the internet’s premier source for boat wiring systems and marine electrical components. Even with just their initial offering, they appear to be an excellent resource for boat owners.

EzAcDc offers engineered boat wiring solutions including:

We recommend their products and services without reservation.

Posted in Boat Wiring, Circuit Protection, Corrosion, Cruisers, Electrician's Log, Gauge Panels, Harnesses, Harnesses-AC, Harnesses-DC, Harnesses-Dash, Navigation Lights, New Products, Pontoons, Quality-Control, Runabouts, Signaling Devices, Switch Panels, Testing | Comments Off

Tinned boat wiring

February 24th, 2008 by Kevin Hannula and Nick Kroes

We recently came across a great piece on boat wiring that addresses the advantages of always using tinned wire.

After making a strong case for spending the (slightly) increased cost for tinned wire, EasyAcDc goes on to cite several boat builders who do just that, including Manitou Pontoons, Crest Pontoons, and Rinker. They then wonder why more builders don’t follow this sensible lead.

It’s an excellent read that we highly recommend.

Posted in Boat Wiring, Corrosion, Electrician's Log, Harnesses, Harnesses-DC, Harnesses-Dash, Switch Panels | Comments Off