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Re: NEXT-12P Charge problem

PostPosted: Tue Jun 07, 2011 10:18 pm
by Coulomb
These readings don't make sense. There's not B+on 4 and the field output is always on, but no charging??? With nothing on pin 4, there can't be any field output.

Did you remove wires to take the measurements?

Re: NEXT-12P Charge problem

PostPosted: Tue Jun 14, 2011 4:06 pm
by drs
Did not remove any wires to take measurements. Had an electrician troubleshoot and he couldn't figure it out other than "the regulator's bad". I may have screwed up transcribing the numbers but they are on the boat and I won't have access to them until this weekend. I ordered a refurbished 12P from you. If it works I'll send the other one back for repair so will have a spare.

Re: NEXT-12P Charge problem

PostPosted: Sat Jun 18, 2011 6:11 am
by drs
I repeated all voltage measurements again and got the following table 9 measurements:
1) House batt pos 12.86, 12.89, 12.89
2) Parallel 12.86, 12.86, 12.85 (and drops)
3) On/Off 0.008, 12.81, 12.81
4) Ground 0.007, 0.008, 0.004
5) B+ 12.86, 12.86, 12.87
6) Field 0.208, 0.259, fluctuates between 0.048 and 0.062
7) Alt Gnd 0.007, 0.008, 0.004
8) Lock 0.007, 0.008, 0.004
9) Batt. Volts 12.87, 12.86, 12.89
10) T neg 0.007, 0.008, 0.004
11) T pos 0.012, 0.012, 0.009
12) ABS 0.007, 0.008, 0.004
13) Lamp 0.040, 12.36, 12.40

I replaced the regulator with the refurbished 12P I just received and got the following table 9 measurements:
1) House Batt pos 13.74, 13.79, 14.41
2) Parallel 12.88, 12.76, 0.745 (and drops)
3) On/Off 0.005, 12.71, 14.41
4) Ground 0.005, 0.033, 0.061
5) B+ 12.88, 12.66, 14.41
6) Field 0.013, 12.38, 8.0 (fluctuates +/- 0.5)
7) Alt Gnd 0.005, 0.032, 0.096
8) Lock 0.005, 0.030, 0.051
9) Batt Volts 12.88, 12.72, 14.46
10) T neg 0.005, 0.030, 0.050
11) T pos 0.010, 3.013, 2.936
12) ABS 0.006, 0.030, 0.047
13) Lamp 0.004, 12.20, 13.96

The refurbished regulator is obviously working. I will be sending the other one back to be looked at and repaired if possible. Can you provide any advice on if I should consider changing the absorption voltage or absorption time? My house bank consists of three 183 amp hour gel batteries. Thanks,

Re: NEXT-12P Charge problem

PostPosted: Sat Jun 18, 2011 2:46 pm
by Coulomb
The absorption voltage with T+ disconnected should be 14.3 to 14.4.

Absorption time of 1 hour should be enough.

Re: NEXT-12P Charge problem

PostPosted: Mon Aug 08, 2011 5:04 pm
by Wolfgang
Here are the numbers to Table 9
1 13.83 13.4 14.3
2 variable .002 .157
3 .007 13.8 14.6
4 .009 .129 -.013
5 13.79 12.59 14.29
6 .006 12.47 4.29
7 .006 .02 -.025
8 0 .02 -.012
9 13.82 13.4 14.38
10 0 .02 -.011
11 .22 4.78 4.8
12 0 .03 -.011
13 0 .03 -.007
I have a Catalina 2002 with 3 batteries of 4-D (540 amp hrs total). I had the battery rep load test them and they were all good.
I have a Amptech alternator ( which I just had bench tested yesterday) He said it was running hot but still functions.

Here is my dilemma. In a normal cycle, on shore power the batteries start full. When I am at anchor with only the fridge on ( 5.5 amps) the xantrex shows my battery percentage dropping. I cannot stay at anchor for more than 40 hours. Last year we stayed 72 and still had 65% batteries. This year,when I start the motor to go home, the amp from the alternator is 80 amps in for about an hour. Then it drops into absorption mode and shows 5-7 amps into the batteries. But the batteries at this time are only charged to70%. I motor 4 hours home but the batteries don’t get even up to 75%. When I am back to shore power after 3 days they are charged up again.
There is no wind gen or solar panels. I have a Next regulator P and it is 10 years old.
I thought of increasing the absorption higher but I need you to tell me that this is acceptable. It is still set a 1.16 volts ( 58 Minutes).
Is there anything else it could be?

Re: NEXT-12P Charge problem

PostPosted: Mon Aug 08, 2011 6:33 pm
by Coulomb
A load test on deep cycle batteries does not show battery capacity, just the ability to supply high current for a short time. Your batteries could be only half the capacity you thing they are. Do a capacity test. It will show you what you really have.

Next, you're using a meter to measure battery consumption that is of dubious value. See this post.

What's the current when the regulator switches to float. That's the only real indicator of state-of-charge that tells you whether the absorption time is long enough. It should be if the alternator is producing like it should, and the batteries are accepting the current like they should be.

What are the batteries? After deep discharges some AGM batteries need days or weeks to reach a full charge.

I'm betting that the batteries are the problem.

Re: NEXT-12P Charge problem

PostPosted: Mon Aug 08, 2011 7:11 pm
by Wolfgang
"What's the current when the regulator switches to float."
How do I do this test?
The batteries are marine 4-D Platinium from Batteries Direct. They say 180 amp on each so I x 3 and got 540 amps . But I show only 240 amp hrs on the zantrex when I start. So it is compensating for the 50% part already. I techanically am working with only 240 amp hrs off the top part of the batteries.

Do I get the battery rep to do this capacity test? or can I do it.
We dont abuse the batteries. But I suspected them in the beginning. But that is a $1500 replacement. So I went to all the other options first.

Whats my next move???

Re: NEXT-12P Charge problem

PostPosted: Tue Aug 09, 2011 12:14 am
by Coulomb
You have to monitor battery current before and after switching to float.

You have 3 batteries in parallel that may not even come from the same manufacturer - that's a sure recipe for short battery life.

You could invest in the Ample Power CD and read the book "Living on 12 Volts with Ample Power" so you understand batteries. Sorry, we don't have time to get into all the issue on the forum.

Re: NEXT-12P Charge problem

PostPosted: Tue Aug 09, 2011 8:07 am
by Wolfgang
All batteries are the same from the same manufacturer. I gather that the NEXT reg is then working fine and the batteries would be the prolem? Is that what you are saying?

Re: NEXT-12P Charge problem

PostPosted: Tue Aug 09, 2011 4:30 pm
by Coulomb
Just because batteries have the same label on them doesn't mean they are from the same manufacturer.

The Next Step is doing what it is designed to do.