VoyForums
[ Show ]
Support VoyForums
[ Shrink ]
VoyForums Announcement: Programming and providing support for this service has been a labor of love since 1997. We are one of the few services online who values our users' privacy, and have never sold your information. We have even fought hard to defend your privacy in legal cases; however, we've done it with almost no financial support -- paying out of pocket to continue providing the service. Due to the issues imposed on us by advertisers, we also stopped hosting most ads on the forums many years ago. We hope you appreciate our efforts.

Show your support by donating any amount. (Note: We are still technically a for-profit company, so your contribution is not tax-deductible.) PayPal Acct: Feedback:

Donate to VoyForums (PayPal):

Tue, April 23 2024, 11:13 [ Login ] [ Contact Forum Admin ] [ Main index ] [ Post a new message ] [ Search | Check update time | Archives: 1, 2, 3, 4, 5, 6, 7, [8], 9 ]

[ Next Thread | Previous Thread | Next Message | Previous Message ]

Date Posted: - Friday - 12/29/06 - 3:55pm
Author: Randall
Subject: Thanks Gents...
In reply to: Randall, Murre, M31 's message, "Electrical Question" on - Thursday - 12/28/06 - 5:07pm

I know I've not done all appropriate testing yet, but thanks for the feedback. Was kind of hoping for that easy answer, like “replace the light sockets” or “rub lanoline on the battery terminals and boil the fuses in hot water for 10 minutes”. No such luck.

I do have an amp meter and was all set to do the various gauging you suggest last week, but found I had left the meter ON during some previous adventure and its own 9v battery was dead. Batteries. Damn. After much searching, no spare on the boat. Windy and rainy day--would rather read. No lights--hmm. Would rather nap.

Comments based on yours:
-Wow! Light bulbs w/the old Kanji. And they work over thirty years later? Interesting re 20w. This problem I have became super noticeable when I tried 12v/50w. Nice bright light, just don't crack open too big a book.
-For several years now, I've charged the batteries only by running the engine. An hour or so almost every week at high revs. I cooked my first set by plugging in to shore power and leaving the charger on all the time. Didn't know any better at that point. Charging via engine-only seems to work fine (at least for the starting bat) and helps to avoid the electrolysis in my marina. It also is good for the old Perkins I suspect.
-Thanks for the Calder lead. I have that book and use it frequently, but not for this yet.
-After starting the engine, I switch to ALL on the assumption that that's what it takes to charge all. Never thought to check that both bats may charge regardless of switch position.
-Wouldn't be surprised if there's a leak...all the wiring is original and somewhat ratty aft of the aft cabin bulkhead.
-The batteries are wet cell, deep cycle.


I'll do the other testing you all suggest and get back.

Thanks again.

RR

[ Next Thread | Previous Thread | Next Message | Previous Message ]

Replies:

[> [> Check my logic, please -- Randall, - Tuesday - 01/ 2/07 - 2:30pm

Based on your suggestions (and a little bit of reading in Calder), did the following tests and reach the following conclusions. See if you agree...

After an engine running episode last week and a week at rest in the cold,
Batt 1 (starter) = 12.46 volts
Batt 2 (house) = 11.51 volts (ouch!)

Started engine and ran for 3 hours, 1 hour at moderate high idle (no tachometer at moment) and 2 hours motoring around Angel Island at about 5 - 6 knots.

Immediately after engine shut off:
Batt 1 = 12.58 volts
Batt 2 = 12.05 volts

Over the next two hours and with the master switch OFF, Battery 1 gained in voltage reaching a resting rate of 12.62 (normal); Battery 2 lost voltage, reaching a resting rate 11.96.

Tested for ground fault on Batt 2; none exists.

While engine running, tested for alternator charge rates. At idle, no significant change to charge rates on either battery; at moderate high idle charge rates on both batteries were plus 1 volt...i.e. normal.

Charging both batteries can only be done on the ALL switch (bummer).

Tested the light socket. Voltage sent from the battery and received a the light socket were identical at the moment of test.

Conclusions:
1. Batt 2 is toast. Inability to make maximum charge and loss of charge directly after 3 hours of charging indicates sulfation, or poor charge maintenance by yours truly over its three years (so says Calder).
2. Contrary to my previous belief, my regime of running the engine every week or so is NOT sufficient to maintain the HOUSE battery, especially since it is often drained somewhat by lights, etc AFTER we return to the Marina and shut off the engine (while we clean up, etc.).
3. The “hot sockets” issue is not proved one way or the other, but it appears there is no leak in the line.

One question: shouldn’t the alternator kick a good charge when the engine is at idle rpms? It does when the engine is at high rpms, but not otherwise. (Lose belt or other issue?)

RR


[ Edit | View ]

[> [> [> I get 13.9 Volts - Check you bilge pump too! -- Capt'n Mike - Gypsy Mariner, - Friday - 01/ 5/07 - 9:22am


When you ran your engine at "idle", what was the engine RPM? I have a Balmar 150 Amp alternator that charges each battery bank independently. It will does not put out it's maximum charge amps until it is rev'd a good bit above idle. I will check this weekend, but it seems like the max. charging voltage of 13.9 kicks in around 1000 rpm and the maximum amps are not reached until somewhere between 1250 and 1500 rpm, but I haven't checked the exact rpm so it may be a little higher or lower. My alternator's charging voltage is 13.9 volts, which seems to be about a half volt or so higher than what you are getting.

If the belts are slipping you should hear it happening and get a lot of black belt dust around the pulleys. My alternator belt wakes the dead when it slips! What is the amp rating for your alternator? You may what to pull it and bring it to an auto electrical shop for bench testing.

When you are ready, you may want to look at replacing your batteries with AGM or Gell cells. When they are not in use, they hold there charge much better than wet cells, but they are expensive. After Hurricane Katrina, my slip did not have electrical power (it still doesn't a year and a half later), so I ran a generator and the engine to charge the batteries. I only used the lights and the radio on the weekends in the slip so I did not have a huge demand on the house bank, but the house bank still would get depleted rather quickly. What I wasn't thinking about is that the bilge pump was tied into the house bank and was an automatic that would turn on sometimes and draw quite a bit of power for a short time. This made it almost impossible to stay ahead of the game only charing the batteries for an hour or so ever week or two. Finally I bit the bullet and bought a large 120 watt solar panel with a great "smart" solar charge regulator. I bought the stuff on e-bay and it seems like it cost about $700 total. It can put over 6 amps an hour back into the house bank at high noon. It was the second best purchase I've ever made for a boat (an autopilot being #1). Now I don't need shore power and can leave the Gypsy Mariner alone for months if I wanted to and the house batteries will be fully charged when I go aboard.


[ Edit | View ]


[ Contact Forum Admin ]

Forum timezone: GMT-5
VF Version: 3.00b, ConfDB:
Before posting please read our privacy policy.
VoyForums(tm) is a Free Service from Voyager Info-Systems.
Copyright © 1998-2019 Voyager Info-Systems. All Rights Reserved.