1240p high voltage

Strecker25

Well-Known Member
SILVER Sponsor
Nov 20, 2014
4,905
Rochester, NY
Boat Info
2002 410DA
Engines
Caterpillar 350HP 3126
Bought 4 new group 27’s for our two main banks and a pronautic 1240p yesterday. Hooked it all up and every thing seemed fine but when I fired the charger up and set it to preset 2 flooded the DC voltage went up to 15.1v. The preset is 14.8v max

I had to run, so I shut it all down and didn’t play with it too much but I’m concerned with that voltage. Without the charger on I see about 12.4v using a multimeter right on the posts.

I’ve emailed pronautic to see if it’s a bad charger, but what do you guys think? I’m going to go back today after they sat for a night and try it again.

side note, the previous owner had the port bank positive lead on the batteries with the starboard negative lead (and vice versa on the other side). I looked at the diagram and I don’t think that would matter because both engines are tied together with ground and they all share a common bus bar but it was a little alarming to find that way
 
Good idea to shut it down, That charger is capable of that voltage, but normally, only in a custom mode, but...also in the Equalization Mode looks like it will go to 15.5 VDC. I thought that had to be selected manually, but I'll have to read up on that. I have AGM, they don't require that.

upload_2021-1-18_10-58-41.png


I would factory reset the unit first, then set it up the way you want again, unless ProNautic gives you some better advice.
 
Thanks man, I’m gonna reset it. If that doesn’t work I’ll try hooking up each bank one at a time and see if I can isolate the bad bank or battery (or prove out the bad charger)
 
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Do the reset as mentioned - maybe something got set by mistake. Side note... you mentioned you have new batteries... were/are they fully charged? They should be reading about 12.8V, not 12.4V. 12.4 is actually on the verge of needing replacement.
 
Do the reset as mentioned - maybe something got set by mistake. Side note... you mentioned you have new batteries... were/are they fully charged? They should be reading about 12.8V, not 12.4V. 12.4 is actually on the verge of needing replacement.

yeah, brand new. That was a typo, I want to say they were 12.79v but I didn’t take note. I’ll measure them again
 
After the factory reset if everything still behaves the same give it a few hours but check it regularly.
According to the manual @dtfeld sighted it should only be a max of two hours.
If going into in Equalization mode the mode LED will be RED

typical for FLOODED lead acid is this...
"Equalization time: generally 3-4 hours or 50-75% of the Absorption charge time."
So a couple hours should not harm the batteries, but no more than that

And the pkys.com website is the best site for all things marine electrical I have ever come across.

from the manual:
"Note: It is recommended to disconnect all 12VDC electronics and monitor the batteries while equalizing as this increases battery gassing and increase the temperature of the battery
"

During testing I would leave the battery disconnect switches OFF to isolate any loads. The charger should be connected before the disconnect switch.

If it wont come out of equalization, they need to warranty that unit
 
After the factory reset if everything still behaves the same give it a few hours but check it regularly.
According to the manual @dtfeld sighted it should only be a max of two hours.
If going into in Equalization mode the mode LED will be RED

typical for FLOODED lead acid is this...
"Equalization time: generally 3-4 hours or 50-75% of the Absorption charge time."
So a couple hours should not harm the batteries, but no more than that

And the pkys.com website is the best site for all things marine electrical I have ever come across.

from the manual:
"Note: It is recommended to disconnect all 12VDC electronics and monitor the batteries while equalizing as this increases battery gassing and increase the temperature of the battery
"

During testing I would leave the battery disconnect switches OFF to isolate any loads. The charger should be connected before the disconnect switch.

If it wont come out of equalization, they need to warranty that unit

Thanks, its only a couple weeks old so I'll return and try again if the reset doesn't help. I bench tested it on 2 of the 4 batteries (on a single bank) at home and it worked fine, so something is up

And you're right - I'll have the solenoids off while doing all this testing. The charger leads run into the line side of the battery solenoid so the boat systems will be disconnected while they're disengaged
 
Are you sure of this?
"side note, the previous owner had the port bank positive lead on the batteries with the starboard negative lead (and vice versa on the other side). I looked at the diagram and I don’t think that would matter because both engines are tied together with ground and they all share a common bus bar but it was a little alarming to find that way"

Better retrace; this its not possible as described would short out one battery...

upload_2021-1-18_13-10-53.png
 
@dtfeld
Your 410 with 3126 Cats, do they have 24volt starters with Series/Parallel starter solenoids?
That's the only thing I know of that coulds easily confuse someone.
It would appear to be a cross connect situation but in reality the S/P solenoid keeps everything isolated properly.
24 volt starters / 12 volt alternators dual batteries per engine.
 
Here's the diagram from our original manual. The two large leads for each bank are labeled. Positive and negative pair for port side are labeled "P. Bank" and positive and negative for starboard are labeled "staboard bank"

To answer your question on if I'm sure, not really. I disconnected all 4 batteries and removed them and verified labels. It's possible they just had the port bank in the starboard trays and I didn't pay close enough attention when laying the cables out of the way.

At the end of the day I have to assume (and based on this diagram) that the positive and negative leads labeled "port" should go as a pair to one bank and the remaining "starboard" leads should go to the other, correct?

batteries.JPG
 
@dtfeld
Your 410 with 3126 Cats, do they have 24volt starters with Series/Parallel starter solenoids?
That's the only thing I know of that coulds easily confuse someone.
It would appear to be a cross connect situation but in reality the S/P solenoid keeps everything isolated properly.
24 volt starters / 12 volt alternators dual batteries per engine.

our boat is all 12v, including the starter voltage. I'm headed there shortly to go through it all again
 
All wire routing checks out. 12v systems work normal when off the charger and banks all read about 12.8. Charger on = 15.2v to all batteries.

I took the charger out and I’m taking it home to test but I think it’s toast. The charger leads go right to the line side of the solenoid, so I don’t see how any of the boat wiring or systems would cause it to act up. I’ll report back in a bit when I hook it to another battery at home shortly.
 
Oh boy, now I’m stumped. On the bench it tests fine. Hooked up two banks of batteries and it goes to 14.7v.

I’ll wait for pro mariner but what in the boats wiring could be causing this? I didn’t have any electrical problems aside from the old batteries being bad but they’re old.

I guess the next step is to put it back in the boat and isolate first the dc side then the AC side. I can go straight from the charger to the batteries first (eliminating the DC wiring in the boat) and if that checks out run AC straight to the charger.

I’m using a long extension cord on a 15a circuit in the boat yard so maybe I have odd input voltage?

nothings ever easy :)
 
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@dtfeld
Your 410 with 3126 Cats, do they have 24volt starters with Series/Parallel starter solenoids?
That's the only thing I know of that coulds easily confuse someone.
It would appear to be a cross connect situation but in reality the S/P solenoid keeps everything isolated properly.
24 volt starters / 12 volt alternators dual batteries per engine.

No, all the CAT diesel 410's & 380's of this era are 12VDC to the best of my knowledge.
 
Oh boy, now I’m stumped. On the bench it tests fine. Hooked up two banks of batteries and it goes to 14.7v.

I’ll wait for pro mariner but what in the boats wiring could be causing this? I didn’t have any electrical problems aside from the old batteries being bad but they’re old.

I guess the next step is to put it back in the boat and isolate first the dc side then the AC side. I can go straight from the charger to the batteries first (eliminating the DC wiring in the boat) and if that checks out run AC straight to the charger.

I’m using a long extension cord on a 15a circuit in the boat yard so maybe I have odd input voltage?

nothings ever easy :)

I assume you did not wire it into the boats AC system for testing (assuming your on the Hard still)? I wonder if the extension cord is causing some issue. If it works on the bench as expected without the extension cord, I doubt its the charger.
 
I assume you did not wire it into the boats AC system for testing (assuming your on the Hard still)? I wonder if the extension cord is causing some issue. If it works on the bench as expected without the extension cord, I doubt its the charger.

correct. Tested on the bench with just an old 12awg ac cord that I chopped the end off. I didn’t pay that close attention to the AC voltage or current draw in the yard, and I’m having to run 100’+ of extension cord to get to an outlet in the boat yard. I’m thinking I’ll put it all back together and check the AC side, then run AC directly into the charger like at home.

The AC input in the yard right now is 100’ extension cord, into my 15a->30a adapter, into 30’ of shore power cord, into my shore power inlet. The other oddity is the charger is putting out nearly zero amps because the batteries are charged it’s just jacking up the output voltage. Wondering now if it’s dirty power input causing some wackiness
 
Are you sure of this?
"side note, the previous owner had the port bank positive lead on the batteries with the starboard negative lead (and vice versa on the other side). I looked at the diagram and I don’t think that would matter because both engines are tied together with ground and they all share a common bus bar but it was a little alarming to find that way"

Better retrace; this its not possible as described would short out one battery...

View attachment 97899
If it's wired like this then you have a dead short. A quick sketch of how it should be for a 12 volt system -
12V battery Configuration.jpg
 
If it's wired like this then you have a dead short. A quick sketch of how it should be for a 12 volt system -
View attachment 97955

thats how it’s wired (your drawing)

the previous owner didn’t have the wires flipped but rather just the port wires on a different battery bank than SR has in the drawings. The port +\- lead pair and starboard +\- pair were properly connected to their respective batteries and the line input on the solenoid. The batteries were just physically in different trays than what the manual shows
 
correct. Tested on the bench with just an old 12awg ac cord that I chopped the end off. I didn’t pay that close attention to the AC voltage or current draw in the yard, and I’m having to run 100’+ of extension cord to get to an outlet in the boat yard. I’m thinking I’ll put it all back together and check the AC side, then run AC directly into the charger like at home.

The AC input in the yard right now is 100’ extension cord, into my 15a->30a adapter, into 30’ of shore power cord, into my shore power inlet. The other oddity is the charger is putting out nearly zero amps because the batteries are charged it’s just jacking up the output voltage. Wondering now if it’s dirty power input causing some wackiness

100' of extension + a couple connections +30 feet shore power cord + x ft of internal wiring? You are looking at a significant voltage drop over that distance. Assuming you had at least 110 VAC (not a given in a boat yard) at the outlet, you could be getting into the realm of where the charger no longer can function properly. A 100' 14ga extension cord will cost you about 6% of your voltage. All the other wiring will cause more and cumulative loses.

Check the AC voltage at the charger when at the boat and post up what you have. The further you are from 110-120 VAC the more issues you will have.
 

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