Charger on 290 - 2001, need a little help.....

[poormonkey]

Well, I have been away from the boat for about two weeks, and I stopped by it today. I didn't have much time to spend at the boat due to having to catch a flight out of town for work. So, I get to the boat, and I notice that the battery meter inside the cabin wasn't reading any voltage. So, I flipped on a few of the dc breakers and I find out I have no battery power. So, I take my volt meter and jump down and measure the battery voltage. The furthest one forward reads 12.8volts. The two located behind that one each read only 2.8volts. These are brand new batteries that were just put in on July 7. So, something must of drained them while I was away from the boat. I find out the hard way, that I should turn off the battery switches when I leave the boat.
Ok, this is my question, so I flip on the converter switch, since I am plugged into shore power. I jumped down and looked at the Professional Mariner flyback 20-3 battery charger. The LED light on it was red, but I noticed it pulsing a bit, from a duller red to a brighter red. Keep in mind this if the fist time I have used the converter, so I don't know if this is normal. I stuck my volt meter on the two batteries that were dead and then the red LED light would go from the duller red to the brighter red for about a second at a time (a second on and off, and that repeats), and on my volt meter the batteries would read from 2.8 volts to like 3.1 volts.
So, is this normal? Is the battery charger running some type of a trickle charger or a self load test on the battery before it will charge it? I didn't have much time, so I left the converter on and I had to run to the airport. I hope this was safe to leave on. What do you think? The charger is working normal? Or is something wrong with the unit? Also, the ammeter on the charger was always on 0 and it didn't move. I won't be back till Thursday evening, so I am kind of worried about leaving this on while I am away.

I read this on another post

you may have to wait 2-3 mins before charger "kicks in"

I know I didn't wait 2-3 minutes before reading the voltage, so maybe this is was my problem :smt100

 

[MLauman]

Since you have 3 batteries, most likely the good battery is just a starting battery for one of the engines (twin, right?). The other two are paralleled (possibly via a switch) in a bank and serve the starter for the other engine as well as providing the 'house' power. When you leave the boat you will need to either: switch off the batteries or leave on the charger (what I do). The Flyback 20-3 (assuming its working properly) is a 3-stage charger and will properly maintain your batteries for extended time periods. But you still need to keep an eye on the fluid levels.

That said, what you are describing does not sound right. My charger (Flyback 15-3) will kick in immediately when a battery is significantly low. Sounds like either your charger is not functioning correctly or you have a wiring issue. There are 3 charging leads coming from the charger and each needs to go to a seperate battery. For best results, the batteries should be otherwise isolated during charging to avoid 'fooling' the charger.

There are also fuses inside the charger case for each lead, IIRC. It sounds like the charger is only attempting to charge the 'good' battery. You should see upwards of 13 volts with your VM on the the battery terminals when the charger is running.

So, I would:

1. check the water levels - @ 2 volts you probably have low fluid and may have diminished the life of the battery.
2. check the wiring - seperate charge lead to each battery.
3. check the fuses - disconnect shore power first!
4. check the battery switch settings. Selecting BOTH can confuse the charger.

 

[poormonkey]

So, I would:

1. check the water levels - @ 2 volts you probably have low fluid and may have diminished the life of the battery.
2. check the wiring - seperate charge lead to each battery.
3. check the fuses - disconnect shore power first!
4. check the battery switch settings. Selecting BOTH can confuse the charger.

1. The batteries were just installed in July of this year, so I would hope the fluids are ok. But, I will check them on Thursday when I fly back home and can get to the boat.
2. I did check this, and each battery has it's own lead from the charger.
3. I am assuming the fuses are internal to the charger unit? I didn't see any inline fuses between the charger and the batteries.
4. What should it be set to? If my memory recalls, it just has "on" and "off", I didn't see "both" on either the starboard or port side battery switch.

 

[MLauman]

3. yes, internal fuses.

4. You may not have a BOTH switch if your house batteries are directly connected together (pos and neg). In this case, if one of the two batteries is low the charger will be unable to sense this and will think that both batteries are at a level somewhere in between. Thus, it will put out the same charge rate on both outputs. This could mean that one battery is being overcharged and the other undercharged. So you can end up with a battery that does not have sufficient charge and another that has been cooked.

Having the 1-2-BOTH-OFF switch between them allows you to isolate them so that the charger can treat them individually.

 

[poormonkey]

Here is a response I got from Pro Mariner on the unit..........


-----------
To test the charger remove all the DC wires, turn the charger on and the
output on all positive posts should be 14.6 volts for lead acid or AGM
batteries. Continue to run the charger and after four hours the voltage
should drop to 13.3 volts. This confirms the charger is going to the
float stage and the charger is most likely operating properly. If the
charger passes this test the source of your problem is most likely the
batteries.

Robert Tutwiler
Pro Mariner service department
800-824-0524
603-766-7610

 

[boatmailster]

leave charger ON for about hour or so and than check voltage.
because 1 battery is OK and 2 other ones are very low charger has to make-up for that difference.
it usually kicks in instantly with batteries 9-11v but having only 2.8v on battery requires very slow charging or plates can overheat
and explode.
next time turn off all battery switches and leave charger(converter) on.
bilge pumps don't need battery switches to be on in order to work automatically

 

[skolbe]

Pro Mariner does offer some trade in options for chargers.

 

[poormonkey]

Well, it was the internal fuse that was blown. However, what a pain to change it out, you have to disconnect the incoming power (110Vac) and then disconnect the three batteries and the ground (DC) to get the bottom off to access the fuse. Why didn't they make the fuse reachable from removing the top cover, so you can leave all the important wires connected. What a bad design, I hope they have improved it. :huh:

 

[boatmailster]

Well, it was the internal fuse that was blown. However, what a pain to change it out, you have to disconnect the incoming power (110Vac) and then disconnect the three batteries and the ground (DC) to get the bottom off to access the fuse. Why didn't they make the fuse reachable from removing the top cover, so you can leave all the important wires connected. What a bad design, I hope they have improved it. :huh:

because that fuse is not user replaceable :wink:

usually when that fuse is blown there is an internal problem with charger or charger was turned ON with all accessories on (lights, radio, try to start the boat with charger on and batteries being low etc)
be sure install exact same type of fuse - it is fast "blow" type not regular "slow blow" type or next time your electronic board inside charger may burn before fuse blow