battery wiring

P

Pacific Blue

New member
Hello All,

My wife and I recently purchased a 22 Cruiser. We brought the boat north and put it under cover until the weather improves. Upon storing it I removed the batteries. There were at least 20 wires hooked up to the batteries. I took a photo and diagramed the set up, but will be challenged to replicate the connections. I am wondering why most of these wires do not run through the circuit panel. Electrical is not my strength, but intuitively this does not seem like the best set up. Any input is appreciated.
 
I just added another fuse box and ran a lot of the secondary wiring to it leaving just the positive and negative cable running to the batteries. If you look on page 5 in my album i took pictures of the process. I'm not great at electrical things either and it's not the greatest job but it might at least give you some idea's. Tug
 
The only thing you should have going to your batteries are the bilge pump wires (fused within 6" of battery), the battery charger cables if one is installed (also fused within 6" of battery). And the main DC Panel Pos & Neg cables of appropriate size (depends on the total load (all electronics) of you system)(also fused within 6" of the battery). All other wires should terminate in the main DC panel.

Hope this helps
 
I see that you mentioned "batteries", so don't forget the main feed to the engine(s) for the 'Start' Battery and it will be separate from the 'House' battery.

The 'House' battery should feed the Power Panel and wired and fused as noted before to service all other devices.

If you have an automatic bilge pump, then that should be wired as earlier recommended; else run it from the power panel through a dedicated fuse and power switch.

There are several pictures and diagrams available here to suit your needs.
The electrical system diagram under Sea Angel may be of help to you.
http://www.c-brats.com/modules.php?set_ ... _album.php

Art
 
Pacific Blue,
One of the challenges will be to be sure that you get the proper wires back on the ground or negative and positive circuits appropriately.

I personally only run the bilge pump "auto" plus wire and the battery charger wires directly to the batteries. There are heavy cables (such as 1/0) to the battery "on, off, 1 and 2" switches, or similar switch (or combiner). From there there, there will be the appropriate cables to the outboard, a main fuse block, which is right by the batteries (usually 60 or so amps, depending on what the loads will be on the console distribution panel).

One exception may be the Wallas stove--many boats have this rigged directly to the battery. As noted any wire, except the heavy cables to the outboards, needs to be fused within 7" of the battery (there may be an exception in that distance, where you have a heavy cable to a combo switch.--there the fuse is right by the switch. Also all positive terminals need to be covered with a boot, to protect from a short circuit if some item were to accidentally drop across the terminals (either battery or switch)

All of the other circuits, go thru one or two fuse blocks behind the console. On the C Dory 22, I recently purchased, I am adding another 12 circuit fuse block. When you are re-doing the wiring, label all of the wires and sort out where they go, and what they do!
 
Thanks for all the thinking on this.

After your input I have decided to go ahead and install a charger/inverter while I am at the task of correcting the battery wiring.
 
Since we are talking batteries...

Besides the CD-22, we have a 32' Jayco Designer 5th wheel trailer. It is an older unit (1997) but very well built: oversized converter, 50 amp service, etc. We have never had an electrical problem with it.

BUT the battery wires are connected to the opposite terminals one might expect. The ground wire (which one can not confuse: it attaches directly to the frame in the battery compartment) goes to the + battery terminal...and, of course, the other wire (which leads into the trailer) goes to the - side.

Since I am presently in Burundi, let me ask in French: Pourquoi donc? WHY? Can anyone explain? (I have labeled the wires, so as not to get them confused...as this situation is, for me, counter-intuitive.)
 
Thanks for all the thinking on this.

After your input I have decided to go ahead and install a charger/inverter while I am at the task of correcting the battery wiring.
 
Wayne McCown":2ssferle said:
Since we are talking batteries...

Besides the CD-22, we have a 32' Jayco Designer 5th wheel trailer. It is an older unit (1997) but very well built: oversized converter, 50 amp service, etc. We have never had an electrical problem with it.

BUT the battery wires are connected to the opposite terminals one might expect. The ground wire (which one can not confuse: it attaches directly to the frame in the battery compartment) goes to the + battery terminal...and, of course, the other wire (which leads into the trailer) goes to the - side.

Since I am presently in Burundi, let me ask in French: Pourquoi donc? WHY? Can anyone explain? (I have labeled the wires, so as not to get them confused...as this situation is, for me, counter-intuitive.)
Click to expand...

Several possible explanations are available:

1. The battery wiring is correct, someone put the battery in backward (reversed).

2. As long as the charger is reversed as well as the battery and the unit (trailer) is not connected to any polarity sensitive electronics, the unit is electrically isolated and it makes no difference to most loads (on the 12 volt circuits) whether the polarity is reversed. The exceptions to this wold be 12v DC motors, which would run backwards, and electronic devices, such as a GPS, stereo, etc.

3. The unit is a Southern Hemisphere Export Model, intended for upside down electrical and magnetic operation.

4 The assembly of the trailer took place in France, where they want to be intellectually right, regardless (or irregardless) of the practicality of the solution. Go ask THEM in French. You won't understand that answer, either.

5. It makes no difference as long as the blender in the galley puts out Margaritas as fast as you can drink them, no?

Joe. :teeth :thup
 
First converters for RV's are far different than marine battery chargers. The Converter is designed to give a steady output of 12 V DC current (actually probably 13.6 volts usually)--and only a trickle charger function--or a few amps. It is entirely possible that the RV may have been built with a entirely different type of electrical system---and some older vehicles had a positive frame system (although the vehicle and RV should have the same type of system).

Pacific Blue--an Inverter charger may be sized for far larger batteries than you have on your C Dory 22--for example I have a Magnum (actually a marine unit) pure sine wave inverter of 2500 watts with a charger of 130 amps in my RV--there I have 6 220 amp Golf cart batteries.

The usual group 24 batteries on a C Dory would normally not take much more than a 20 amp charger--and would only sustain a 1000 amp inverter for a 30 minutes of use. Of course one could put in larger batteries--but consider why you want an inverter and what you want to run on it.
 
Thanks Thataway,

I was thinking that the inverter would allow me to use ac wired equipment through a few gcfi's. Right now all I have is one dc outlet. For clarification, are you saying that the typical battery type for a 22 cruiser would only allow for 30 minutes of draw down (50% of battery capacity) @ a 1000 watts?
 
Typically the C Dory has a group 24 battery (the group # refers to case size, and there can be several variations in that case size). Group 27 and Group 31 are often upgrades.
Group 24: 70-85 Amp hours
Group 27 85-105 Amp hours
Group 31 95-125 Amp hours

Half of the amp hour capacity is generally available, but when pulled down rapidly--as with an inverter the amount available is less. So a group 24 may have about 40 amp hours available. 12 volts vs 120 volts, means that 10x the number of amps are drawn from a 12 volt battery vs the 120 volt mains...For a simple example 1200 watts is 10 amps with a constant voltage of 120 volts. Converting this same load (a hot plate or heater--pure resistive load to 12 volts would be 100 amps. That 100 amps would last less than 30 minutes on a group 24 battery. The problem is that high power draws pull the battery voltage down rapidly--in a small battery bank.
Yes you can run a 800 watt micro wave (which will probably draw closer to 1000 watts) for 5 to 10 minutes off a group 24 battery, but at a cost. Four our 1000 to 1500 watt inverters we usually had two sets of group 31 AGM batteries, which gave us about 250 amp hours available. This left some over for the refrigerator and other house draws.

Generally you don't like to charge batteries more than 10% of their amp hour rating--so an 80 amp hour battery would be charged at about 10 amps safely. You can monitor temperature and then charge at a higher rate. The Magnum inverter charger I referred to earlier has a temp sensor, and regulates the charge by battery temp. You will see 100 amps or so charge, until the temp gets up to abut 120 degree F--then the charge will taper off. (remember this is for a 660 amp hour battery bank). This is why I tend to limit the battery charger on a C Dory 22 to 20 amps. If you have larger banks, you can put in a 40 amp charger--but don't go to 100 amps until you have somewhere in the 600 amp hour battery bank range.

I make some broad assumptions here--and didn't go into all of the technicalities.
 
This helps sort this out a lot. Thanks.

Given my current and planned amp hour load, current system set up and planned excursion details

Amp hour load: current--chart plotter, 3 cabin lights, marine radio, wallas stove,, downriggers, 2 bilge pumps, raw water wash down, trim tabs, planned--windlass?, pot puller, radar, stereo

Current system set up: (1) 2005 90 hp Honda, (1) 2005 8hp kicker (remote control throttle), (2) 24 group size batteries (6 years old) in starboard lazarette (there is a 1, 2, both, off battery selecter in the lazarette), and an empty port lazarette. As mentioned earlier in the post, practically everything is currently hooked to the batteries

Excursion details: mostly 2 - 3 overnights at a time, with an average of a 140 mile round trip, with occassional overnights in a marina prior to excusion

does anyone have any reccomendations for straightening out what i have now

Your ideas are much appreciated!
 
FYI;
The HONDA 90 has only a 16Amp alternator which fine for all the equipment you listed with normal duty cycle useage to maintain the load and charge on the batteries.

You may want to look into the, BEP Marine, Voltage Control Relay(VSR) setups that would always protect your selected start battery. Once it is up to parr at 13.t volts, it then energizes the VSR to charge the house battery.

When you shutdown the engine, the house battery and start battery will supply power till the start battery terminal voltage drops to 12.8 volts, at which time the VSR deenergizes and only the house battery supplies power to the loads. This protection will allow you to restart the engine when needed and not have a dead battery to worry about.

You still can isolate each battery and load just as you are doing now, but it is automatic and you will not have to worry about blowing up your alternator if you switch the selector between batteries while the engine is running. BIG expense is this happens. I have had this on Sea Angel since 2005 without a single problem. Great investment.

Art
 
You might go to the forum on Electrical and Wiring, page 2. See Bus Bars and author Tug.

He had the same issue, and he posted photos in his photo gallery. Click on the photo lead under his name on the left.

Tim & dave Kinghorn
 
Thanks to everyone for the information, direction and ideas. I look forward to getting this sorted out soon. I'll post an update when the work gets started!
 
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