Wiring a DC-DC Xantrex echo charger

[KREW2]

The reason I posted this question is because I do like to get things right, But it's all getting a bit heavy. I've managed for years without a windlass, so if for some reason there are times when the battery is not charged up enough I will just have to do it manually, still gotta be easier than hauling by hand.
Hi Cimo I'm still not sure what route to go down. All the gubbins you need to buy, Charger DC-DC still need cable, plus extra battery and box, and a bit of construction to install it. think I'm going to go down this route http://www.safety-marine.co.uk/downloads/Lofrans-Kobra-Windlass-Instruction-Manual.pdf?did=239 wired to the main battery bank.
Just waiting for someone to pull this method apart. I which case I will not wire it and do it by hand.

 

[Stu Jackson]

Sounds good to use the house bank for power. Here's an excerpt from the West Marine Windlass DIY section (http://www.westmarine.com/webapp/wcs/stores/servlet/westadvisor/10001/-1/10001/Windlass-Wiring.htm)

Power Considerations
Though some experts may disagree, we believe that the best way to power a windlass is from the existing house battery bank, rather than from a separate battery in the bow. Not only does a dedicated battery add to the already appreciable weight of the windlass, anchor and rode, it presents charging and maintenance difficulties. The weight and cost savings of using short cables between the battery and the windlass, instead of long ones from the windlass to the house battery bank (which is presumably far away), is offset by the weight and cost of cables necessary to charge a bow battery. Charging cables must be sized to handle any potential charging load. This is liable to be less than the maximum windlass draw, but could still be 50-100 amps, so the cable size would be almost as large as those required to power the windlass from the house bank. In addition, charging a battery over a long distance can involve large amounts of current flow for an extended period of time (assuming a heavily discharged battery), which in turn could lead to a voltage drop, heat build-up, and/or a large electromagnetic field. In contrast, a windlass draws current in short bursts, so the cables supplying it will not be under continuous use.

 

[halfway]

KREW2: There is no way to pull that apart. It is the way the majority of boats from 9m to 90m are wired. Although, as they get bigger the voltage goes up. (24v, 110v)

I have however got three extra suggestions:
1. Put the cables in to their own separate flexi conduits. Making sure that any overheat events could not cause a short. They also make sure that there is air around the individual wires for cooling.

2.The small wires should be run as separate leads to the bow as they should not see the voltage drops of the main motor currents. The huge stalled motor current, as it starts, would lower the available voltage to the solenoids. Pulling the contacts in as forcefully as possible will prolong their life.

2. Obviously the positive has a breaker located as close to the house battery as possible. But fitting an isolator (near the battery) in the negative wire is also useful. Also, make sure they isolate all the control wires. So the 5amp fuse is on the non-battery side of the breaker. The negative small wire is the non-battery side of the isolator.

The idea is that after some time the motor and windlass can develop leakage paths to the chain. Powder from the worn brushes etc. In an anchorage you will be using the anchor chain as a anode! So by isolating both power leads (+ve one with the breaker and the -ve with the isolator) there is no chance of the chain becoming zinc free.

If however you have a steel hull it is impossible to stop using the chain as an anode. However, leakage paths in the windlass can cause corrosion in the hull. It is essential not to have more than one negative path to a metal hull. So fitting an negative isolator is normally recommended.