|
|
Post by nornaj on Nov 23, 2012 18:04:47 GMT
Hi, Guys
I am presently working my way through a number of electrical issues on my 2010 SO39i. Most of these go back to the original commissioning (battery wiring and inverter operation).
We had a 100 amp Balmar alternator fitted and a smart regulator. The maximum charge we are now getting from the alternator is around 30 amps (and I am not sure that we ever got any more than that, even when new).
One suggestion is that we may have fried some of the alternator diodes through incorrect switch sequence on engine shut down.
The boat has the keyless B-Type panel. Shut down sequence should be "stop" followed by "off".
It does seems bizarre that a modern panel would be designed so that "off" followed by "stop" (easily done) would be catastrophic.
One of my next steps is apparently to check for AC current at the alternator output (if I can work out how to do that).
Meantime, however, I would appreciate anyone's confirmation that the mis-sequencing would cause the problem and whether there is any way to make it idiot proof.
Many thanks
NornaJ
|
|
|
|
Post by rhb on Nov 23, 2012 21:24:19 GMT
Unless there is something very non-standard about your boat wiring it should make absolutely no difference to the alternator diodes what you do at the engine control panel.
The thing that will fry alternator diodes is if you operate the engine / alternator with no load connected to the output of the alternator.
Unless someone modified your boat wiring significantly on the output side of the alternator it wouldn't matter what engine panel switches you operated on a modern Jeanneau in any sequence since neither of the engine panel switches are capable of disconnecting the alternator output from the batteries.
What are you using to measure the output of the alternator? If your house batteries are well discharged (discharged to 50-60% of their total capacity) and you see only an initial 30 amps using a reliable instrument (an aftermarket battery monitor or a clamp-on ammeter) then something is most probably wrong with the alternator or regulator. If you initially see more than 30 amps going into the batteries but it tapers off fairly quickly to a low value that's almost certainly not a diode problem.
It takes about 10 minutes to remove the alternator on our boat, probably not much more or less on yours. The best way to determine what's going on would be to remove the alternator and take it to any competent automotive electrical shop where they can test it. This would let you quickly determine if the alternator is good or bad.
If it's good (it most likely is) then the next step is to evaluate the performance and setup of the regulator. This can be done at the shop if you take it in with the alternator or, a bit less scientifically, on the boat.
Balmar regulators ship with a default program that provides results not much better than a standard alternator. In order to get the full benefit of external regulation they need to be tweaked using their advanced settings.
The charge acceptance of the standard Tudor SLA batteries provided with many Jeanneau boats is not very high event when they're new. I don't think that these standard batteries are true deep-cycle batts and they don't seem to do very well being discharged deeply as often happens. The scenario that can kill them prematurely is to take the boat out, run the house bank well down, then charge them using only the engine for a few hours on the way home. This would typically recharge the batteries to 75 - 80% of their capacity and over time cause them to lose capacity. To get the most out of the batteries (whether original or after-market) requires that the be recharged to 100% as often as possible and keep them trickle charging after that. This usually means either using your shore power charger or decent sized solar panels (or whatever) if shore power isn't possible. It's very hard to get batteries to 100% using just the alternator, particularly using a stock program on a Balmar (or any) regulator.
The best way to troubleshoot a problem like yours is to systematically remove elements of the system from the pool of suspects.
You can eliminate the alternator pretty easily by testing it; you can eliminate the possibility of loose/corroded cables by examination, you can eliminate the regulator by measuring / observing it's behaviour; You can get an idea of the battery condition by having a reliable / honest / competent battery dealer use their advanced digital battery tester on them.
If the alternator/regulator/cables are working then pretty much the only things left to suspect are the batteries or the charging regime.
Sorry for my rambling response - I'll revisit when I'm a bit more awake and see if I can add any other info that will be helpful.
|
|
|
|
Post by johnbenq on Nov 23, 2012 21:41:36 GMT
The output from the alternator will be determined by the load that it is driving. For example, if the alternator is only charging a battery bank that is full, the output will be very low.
I have never heard of an engine panel having the ability to affect alternator diodes.
The traditional way of "frying" alternator diodes is to disconnect the alternator from the load. This can happen if you turn off standard battery isolation switches while the engine is running. I use the word "standard" as some battery switches disconnect the field current from the alternator when you turn the switch off (or move it from bank to bank) to avoid the problem.
One of the problems that you will have trying to diagnose the fault is that the external regulator controls the output from the alternator. This means that the alternator may be 100%, but if the regulator is faulty you may get incorrect charging voltages.
The quickest way of testing the alternator would be a bench test under load. An auto (or marine) electrician can do this for you.
|
|
|
|
Post by johnbenq on Nov 23, 2012 21:42:58 GMT
My post crossed with RHB's post. Apologies for the duplication.
|
|
|
|
Post by rhb on Nov 23, 2012 23:18:15 GMT
No worries mate, hopefully between the two of us we can help this fellow Jeanneau owner out.
|
|
|
|
Post by rhb on Nov 23, 2012 23:31:20 GMT
A bit more info: Even with the Balmar 100 amp alternator and even if the regulator is tuned for maximum efficiency, you may never see 100 amps charge going in to the batteries. If your 39I has 3 house batteries and 1 start battery, with batteries that are 50% discharged, you might see something like 60-70'ish amps for the first part of the charge cycle. This is due to the limit of the batteries ability to accept charge. As I understand it, batteries have a particular internal resistance when new and this internal resistance increases as the battery ages. The more internal resistance the less charge the battery can accept. If your batteries are sulphated from not being fully charged between uses then the charge acceptance rate will be lower and it will take longer and longer to achieve a full charge, even with a decent shore power charger. There are some pretty good references on the web to learn more about how your system works. Unfortunately there aren't as many really knowledgeable marine electrical system techs as we'd all like. Even very good automotive electrical techs may never have gained experience with deep cycle systems, external regulators, etc, so you may have to learn quite a bit yourself to do the troubleshooting or to support even an otherwise competent electrician. Here's a few links to get started: www.windsun.com/Batteries/Battery_FAQ.htmwww.batteryfaq.org/forums.sbo.sailboatowners.com/showpost.php?p=775433&postcount=1 |
|
|
|
Post by sailbleu on Nov 24, 2012 7:13:51 GMT
|
|
|
|
Post by nornaj on Nov 26, 2012 22:17:37 GMT
Well that's a relief...
Thanks, guys.
Will now step gingerly along the paths suggested.
NornaJ
|
|
