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  Topic Review (Newest First)
01-13-2009 11:00 AM
timebandit I have my outboard charging wired to the the output of the perco battery switch with a trowling motor plug.

In the days when before installing an onboard charger I just added a male plug from the charger to the to the boat just like it was the outboard.

Charger set outside and by using the battery select switch I could charge one--two--or both.

If you don't remove you motor as I do you might just "T" into these wires.
01-11-2009 04:25 PM
tager OK. I solved the problem. The PO was kind of stupid when it came to wiring, which is incredible considering he once had this boat as a totally electric powered vessel (big solar panels, wind generator, no sails, no motor).

Everything was wired direct to the battery terminals.

After about an hour of wiring things to the built in terminals, I disconnected the battery, and put in a new one. Same problem. I went to the 110 receptacle on the boat exterior, and realized that whoever installed it seemed to neglect drainage, and rainwater had collected in it. Ostensibly, there was a short here, because clearing it out solved the problem.
01-11-2009 10:06 AM
thekeip The West Marine 30A portable is a nicely priced smart charger that I have installed on several occasions where ignition protection is not an issue. 30 amps with a sizeable (1/2") volts / amps display, and front panel charge profile selector is very attractive. Of course, the clips need to be replaced per ABYC.
01-11-2009 07:19 AM
patrickrea I went through this when I bought my boat. ABYC regulations don't allow alligator clips on board as they can not only pop off but the springs die and then don't clamp at all. Portable chargers are not ignition protected and can ignite the hydrogen gas coming off the battery or other vapours in the bilge as in gasoline fumes.

Buying a good charger means you reduce the odds of the above happening but it also extends the run time on the battery and the life span of the battery.
01-11-2009 05:55 AM
Rockter I would not leave such a charger unattended.
Hook it up to the batteries if you wish, but stay on board when the charger is active. Spend the night on the boat is the way I do it. If you leave for any reason, just kill the power and pull the leads off. Kill the power first..... don't pull the leads off when the charger is live. I have recollections of neglecting that advice in open air in a workshop (no compartment).... bang! ... and acid spray everywhere.

Hydrogen does not collect in bilges, as it is lighter than air, so reasonable ventilation of the battery compartment and you should be OK. I just leave the cover off it while charging.

Watch the electrolyte level. It tends to drop.
01-11-2009 01:49 AM
tager I have a Guest Charge Pro Model 2613. It is only connected to one deep cycle battery right now. The red LED on "Trolling Batteries" is blinking. I have unplugged the unit and stopped using the battery for the time being.

Does anybody know what a blinking red LED means in this situation?

Voltage Reading:

Battery at terminals (charger off) 11.4 V
Charger at terminals (charger on) 11.5 V
11-05-2008 08:34 AM
xsboats I have used a household lamp timer to turn on and off automotive chargers. As a liveaboard for awhile, I calculated my amp hour usage to calculate how many hours a day to set the on position for. As for maintenance charging, a few hours a day was enough to come back to a fully charged but un- boiled battery bank.
11-04-2008 12:19 PM
AdamLein Thanks for the responses, folks. The way I've been planning on using this charger (which is indeed of the intelligent three-state variety, delivering 13.5-14.4 volts as necessary) is to top up batteries occasionally as I notice that its voltage has dropped too low. I've always attended closely to the process as I've never been quite sure what to expect. Prior to April of this year, the batteries were alternator-charged but then I swapped in an alternatorless (and pull-start) motor while the old one was under repair.

The boat's wiring is as follows: cables from the two batteries run to a Perko battery selector and thence to a pair of terminals in the engine compartment. What I'd really like to do is hook directly (and temporarily) to the terminals in the outboard engine compartment or, failing that, to run battery cables out of that compartment to someplace free from potential gas buildup (unlikely due to the enormous hole in the transom that the motor sits in) and not fire-prone. In my ignorance of such things, my concern there was that running a charge through the switch or other boat circuitry might be hazardous to that circuitry. The instructions were detailed on how to avoid the risk of spark using leads (basically, establish the final connections as far from the battery as possible).

What I've learned from your replies is twofold:
1) Not a problem to charge onboard if attended and for short periods of time (like a couple of hours).
2) My batteries should be inside boxes.

New questions that have been raised are somewhat more theoretical. I've seen wiring diagrams of, and mikehoyt mentioned, circuit hooked up to one terminal of a voltage source, and thence to ground. I was under the impression that current only flows in closed circuits, so what gives? On the practical side, when charging a battery, what's the difference between clipping on to both terminals, or to just one terminal?
11-04-2008 11:35 AM
camaraderie I would caution against leaving any alligator clip type charges on the boat and unattended. I have personally been witness to a boat next to me burning to the waterline when the charger shorted out and the owner was not aboard.
I don't think there is any problem using short term and while you are on board the boat.
11-04-2008 10:03 AM
mikehoyt The Guest Charge Pro that Tommays pictured above is a portable 3 stage charger. It is extremely useful in that it can be used to charge your batteries over the winter periodically or in Spring when they are removed from your boat. It is also a marine charger that will not fry your batteries if left connected so can be used in the summer.

I purchased one of these in Spring 2000 and have used every year since. I did this in place of the built in Guest charger that was also 6 AMPs and the same price at the time. I would leave the alligator clips connected and plug in the charger when at dock.

As the boat I had at the time did not have 30AMP shore power and had an outboard motor with no alternator this was the main source for recharging the batteries. I would attach one terminal to the back of the battery switch and the other to the ground in the lazarrette and could in that manner charge battery 1, 2 or both according to the setting of the battery selector switch.

I had no problem with this charger hurting the batteries and have left batteries plugged in for weeks at a time both on board the boat and when stored in my garage.

It is a great little charger and I am glad to see it is still available. I would not hesitate to buy it again,

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