AC Charger Help

hd2002hd

Member
Jul 20, 2010
457
St. Louis
Boat Info
1996-Sea Ray 215 Express Cruiser/1996-Sea Ray 330 Sundancer/1998-Sea Ray 400 Sundancer/1996-Sea Rayd
Engines
5.7 Mercruiser/454's/454's w/V drive/120HP
1998 400 Sundance. Came down a month ago to check on the boat and the batteries were dead. Turned on the AC converter and it popped up to ~5 amp draw which was pretty normal. Batteries charged overnight and all was good. Came down to dewinterize this weekend and batteries were dead again. Flipped on the AC converter up to about 5 amps and left it overnight. Next morning the batteries weee still dead and the AC converter was drawing zero amps. Flipped it off and back on. The amp needle would bounce but go back to zero. I assume it is bad. Any way to text it or troubleshoot further?
 
Perhaps check the charger output voltage?
 
First of all, if your boat is in the water, battery charger should be on all the time. Also if batteries are 3 or 4 years old, they are shot
 
I agree with the charger on, but our marina service manager doesn’t agree. Every time they do anything on the boat they shut it all off. The batteries are less than 2 years old.
 
I agree with the charger on, but our marina service manager doesn’t agree. Every time they do anything on the boat they shut it all off. The batteries are less than 2 years old.
Hard to believe a harbor master would say leave charger off. If you develop a leak, that charger is what will keep you afloat.
 
Yeah, I agree. He claims the older chargers overcharge your batteries and ruins them. I typically leave it on, but if the marina does anything on the boat, they always shut it off.

The charger is a promariner 40 amp charger. I have 2 banks of 2 and the genny battery so a total of 5. I assume it is a 3 bank charger, but not sure. Anyone know? I also assume a new Promariner 40 amp charger with the same amount of banks is a plug and play. Is this a good assumption?
 
You
Yeah, I agree. He claims the older chargers overcharge your batteries and ruins them. I typically leave it on, but if the marina does anything on the boat, they always shut it off.

The charger is a promariner 40 amp charger. I have 2 banks of 2 and the genny battery so a total of 5. I assume it is a 3 bank charger, but not sure. Anyone know? I also assume a new Promariner 40 amp charger with the same amount of banks is a plug and play. Is this a good assumption?

You should look at the Pronautic 1240 as a plug and play replacement. Your marina guy is dead wrong about not leaving the charger on. Even the Promariner you have (assuming it works) would not hurt batteries in good condition. But the new smart charges are vastly better and will help batteries last longer.
 
You


You should look at the Pronautic 1240 as a plug and play replacement. Your marina guy is dead wrong about not leaving the charger on. Even the Promariner you have (assuming it works) would not hurt batteries in good condition. But the new smart charges are vastly better and will help batteries last longer.

Thanks for your help. I actually wrote to Promariner before you replied and they said the same thing. I was reading up on the 1240 and I saw some comments about a reset button on it. This got me to thinking that maybe the one I have has a rest button on it. I looked today while at the boat, but did not see one. Any idea if the original has a reset?
 
Not that I know of. I had a Promariner 30 on my boat that I replaced. It was still working but they are not as good for the batteries as the new multistage ones.
 
Thanks for your help. I actually wrote to Promariner before you replied and they said the same thing. I was reading up on the 1240 and I saw some comments about a reset button on it. This got me to thinking that maybe the one I have has a rest button on it. I looked today while at the boat, but did not see one. Any idea if the original has a reset?

My 1240 stopped charging after I blew a converter breaker. I pressed the Setup button on the front once and it appeared to reset it.
 
Big questions is what is on your boat drawing your batteries flat?

In the month between visits what was left "on" that killed the batteries?

On leaving the ProMariner in the "on" position...... these chargers are extremely smart. If installed, wired and programmed for the type of batteries it will extend the life of your batteries without over charging.

What does your charger show on the front display? There is an LED read out as well as a battery over all health meter of green LED's. If the charger is in a "fault" mode I would start looking for the reason.
 
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1998 400 Sundance. Came down a month ago to check on the boat and the batteries were dead. Turned on the AC converter and it popped up to ~5 amp draw which was pretty normal. Batteries charged overnight and all was good. Came down to dewinterize this weekend and batteries were dead again. Flipped on the AC converter up to about 5 amps and left it overnight. Next morning the batteries weee still dead and the AC converter was drawing zero amps. Flipped it off and back on. The amp needle would bounce but go back to zero. I assume it is bad. Any way to text it or troubleshoot further?
Behind the 12V main disconnect panel are three 50amp breakers that are between the converter/charger and batteries. To access these breakers remove the panel screws and pull the top of that panel away and you will see those three breakers mounted by the hull. There is always the potential for current flowing from the starboard and port batteries regardless of the battery switch position such as for electronic memory, bilge pumps, alternators, etc. For this boat unless laid up you should always keep the converter/charger active as well as AC systems flowing air. BTW if the converter only went up to 5 amps on dead batteries you have a problem..... The best test is to turn on the converter and load the system down (turn on lights, refer, etc) and see if the converter approximates the draw you loaded it with. Oh, and by the way, if the batteries are really dead the charger may determine a no load condition and not go into charge mode.
 
Big questions is what is on your boat drawing your batteries flat?

In the month between visits what was left "on" that killed the batteries?

On leaving the ProMariner in the "on" position...... these chargers are extremely smart. If installed, wired and programmed for the type of batteries it will extend the life of your batteries without over charging.

What does your charger show on the front display? There is an LED read out as well as a battery over all health meter of green LED's. If the charger is in a "fault" mode I would start looking for the reason.
Big questions is what is on your boat drawing your batteries flat?

In the month between visits what was left "on" that killed the batteries?

On leaving the ProMariner in the "on" position...... these chargers are extremely smart. If installed, wired and programmed for the type of batteries it will extend the life of your batteries without over charging.

What does your charger show on the front display? There is an LED read out as well as a battery over all health meter of green LED's. If the charger is in a "fault" mode I would start looking for the reason.

I haven’t had a chance to dig into the cause of the electrical leak, but I have put a lot of thought into it. What I believe is happening is that I wired my stereo amps directly off of the battery. They have an auto on function associated with the head unit, but the head unit has to be turned on from the main breaker. However, I did install a cooling fan for the amps as well. I doubt that it has gotten hot enough for the fan to run, but it does have a thermostat on it that will turn it on at 90* F or so. I assume that would draw some current, but not sure how much current or if it drew enough current to drain the batteries over a month. I do have a 150 breaker going from the batteries to the amps, sp I tripped that yesterday when I was down, but I did not have time to investigate it further at that time.

My charger has a needle and not an LED. I have noticed it registering 2 or 3 DC amps, but that was when the generator was running. With the Benny off and shore power on zero DC amps. Not sure I understand that.
 
My charger has a needle and not an LED. I have noticed it registering 2 or 3 DC amps, but that was when the generator was running. With the Benny off and shore power on zero DC amps. Not sure I understand that.

I didn't understand that the charger was that old. It might be time for an upgrade to one of the newer models. They are quite reasonable.

How old are your batteries? Hope they are still serviceable after going flat a few times.

I just had to drop $750 on 3 new AGM batteries last weekend. Not what I was planning on doing but it had to be done to get ready for the season.
 
I didn't understand that the charger was that old. It might be time for an upgrade to one of the newer models. They are quite reasonable.

How old are your batteries? Hope they are still serviceable after going flat a few times.

I just had to drop $750 on 3 new AGM batteries last weekend. Not what I was planning on doing but it had to be done to get ready for the season.

Batteries are less than 2 years old.
 
I did buy the 1240P and installed. Very easy install as mentioned. However, it doesn't seem to be working properly and I am not sure why. When I run the self test, it always says 'ok". It shows 13.3 volts and I have seen it in standby and conditioning, but never in charge mode. It appears to be reading the 13.3 volts off of the generator battery. I noticed this morning that the other 2 banks had dropped down to around 11 volts due to usage of lights, toilet, stereo, etc., but it never seemed to start or try to charge them. So, any suggestions? Battery isolator? I guess my understanding of the isolator is that it is basically an electrical check valve and only allows power to go one direction. I suppose if it is bad it is not allowing the power to go to the batteries and the genny battery never discharges because it only starts the genny so there is no draw. Any help is appreciated.
 
Your battery isolator is wired between the alternator and the batteries on the load side of the battery switches. Conversely, the output of the charger is wired directly to the batteries. You should be able to isolate the isolator (no pun intended) by turning your battery switches to the OFF position. If it still doesn't charge, it probably isn't the isolator. If the problem goes away it may be your isolator.

You can test your isolator by;

1) Disconnect all wires.
2) measure resistance between the alternator terminal(s) and the battery output(s).
3) reverse the probes and measure again.

You should see relatively low resistance in one direction and not the other. (basic diode test)
 
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Your battery isolator is wired between the alternator and the batteries on the load side of the battery switches. Conversely, the output of the charger is wired directly to the batteries. You should be able to isolate the isolator (no pun intended) by turning your battery switches to the OFF position. If it still doesn't charge, it probably isn't the isolator. If the problem goes away it may be your isolator.

You can test your isolator by;

1) Disconnect all wires.
2) measure resistance between the alternator terminal(s) and the battery output(s).
3) reverse the probes and measure again.

You should see relatively low resistance in one direction and not the other. (basic diode test)

So, if the batteries charge with motors or the genny running, does that eliminate the isolated?
 

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