Charging voltage should be 2 volts battery voltage. The way I was thought was check battery voltage with batteries at rest (no draw or charging) then start engine and battery voltage should show 2 volts above previous reading. If it is higher you have a bad regulator lower most likely a bad alternator.
Sent from my T-Mobile 4G LTE DeviceDoug Mountjoy POYC Pegasus (for sale) Lf38 Significant Other LF39 -------- Original message --------From: RANDY via CnC-List <cnc-list@cnc-list.com> Date: 7/20/17 07:10 (GMT-08:00) To: cnc-list <cnc-list@cnc-list.com> Cc: RANDY <randy.staff...@comcast.net> Subject: Re: Stus-List Voltages An update on this. Monday morning I brought my batteries home (I've got two of these: https://www.walmart.com/ip/EverStart-Maxx-Marine-Battery-Group-Size-29DC/20531539 dated May/June 2014 with relatively light use and constantly maintained by a 3amp solar charger). And I bought this inexpensive charging unit: https://www.walmart.com/ip/Schumacher-Electric-15-Amp-Battery-Charger/46167057. One battery measured 4.7v before charging, and the other 5.7v, according to the charger's test function. Each battery was on the charger for about 33 hours to charge back up to 13.2v / 13.5v and 100% charge according to the charger. I haven't measured their voltage independently after charging with a multi-meter, but I did that at the start of the season and they were healthy. Put one of 'em back in the boat last night and connected it up, and my solar charge controller indicated it was charging, which was good. Before, the batteries had gotten so depleted that the charge controller wasn't indicating it was charging them. Now the only thing I haven't done is test the voltage coming off the alternator and regulator of my Atomic 4 to see if those components are working correctly. But I run the engine so little - a couple of ten-minute bursts per week - that I'm not sure how much charging it would contribute even if the alternator and regulator are working perfectly. Chalk it up to negligence - I forgot to manually pump the bilge when I knew it had ice box drainage and rain water in it, and I forgot to turn off the main battery switch when leaving the boat one day. A few lessons learned in this episode, and I don't really know how much life I took out of the batteries by depleting them so badly. I'll be checking my batteries' charge levels with a multi-meter regularly now, as I don't have any kind of battery monitors (but here's a good article on them: http://www.pkys.com/Amp_Hour_Meters.htm). Cheers,Randy StaffordS/V GrenadineC&C 30-1 #7Ken Caryl, CO From: "RANDY via CnC-List" <cnc-list@cnc-list.com> To: "cnc-list" <cnc-list@cnc-list.com> Cc: "RANDY" <randy.staff...@comcast.net> Sent: Sunday, July 16, 2017 7:12:11 PM Subject: Re: Stus-List Voltages I may have a similar issue. Went out for sail with guests today and discovered my batteries were dead. Couldn't even light the florescent light over the dinette, let alone start the engine. So, left and returned to dock under sail power. Last Wednesday night, no problems with the electrical system. I think the main battery switch may have been left on, running the depth meter and stereo display for three plus days. It's also possible I had a bilge pump cycling. My charge controller was indicating no charging of the batteries from the solar panel. I don't know if that's a byproduct of dead batteries, or an issue with the charge controller or solar panel. I'm thinking I should pull the batteries out of the boat, bring them home, and charge them, then put them back in the boat and see if the solar charging starts working again, and if the batteries drain again (with the main switch off and no water in the bilge this time). I have a multi-meter and know how to use it and can diagnose the system from first principles if necessary. The batteries were new in 2014 and are very clean and have the correct amount of water in them. And the solar charging system has worked flawlessly to date, though its capacity is small. Any suggestions? Especially on what kind of charger to use to charge the batteries? Thanks,Randy StaffordS/V GrenadineC&C 30-1 #7Ken Caryl, CO From: "Dennis C. via CnC-List" <cnc-list@cnc-list.com> To: "CnClist" <cnc-list@cnc-list.com> Cc: "Dennis" <capt...@gmail.com> Sent: Sunday, July 16, 2017 6:14:22 PM Subject: Re: Stus-List Voltages I agree with Jim's recommendations. If you do take them somewhere for testing and they tell you anything less than an hour to test, go somewhere else. Dennis C.Touche' 35-1 #83Mandeville, LA On Sun, Jul 16, 2017 at 6:22 PM, Jim Watts via CnC-List <cnc-list@cnc-list.com> wrote: Tom, battery voltage should be tested after resting for an hour or more after charging. Your charging voltage sounds about in the right range, but you are measuring the voltage coming out of the charging source, not the battery. 13.2 V is about minimum voltage to overcome internal resistance and actually charge the battery. A healthy charged battery will test at around 12.65+ after resting for 12 hours. Each battery will have to be checked individually, so they should not be interconnected for that. Just remove the black wire for testing, you don't have to totally strip them. In addition, get a good battery hydrometer and check each cell for the right specific gravity. My battery guys recommend the EZ Red unit, and I agree. (http://www.ezred.com/product/battery-hydrometer/) I had THREE cheap hydrometers give me similar readings that were nowhere near reality, and that cost me a couple of weeks of anxiety while cruising, and a lot of work taking the three Group 31's out and having them tested for real with a pro analyzer, then reinstalling them. West Marine stores generally have a load-testing type of analyzer if you drag the batteries in to the store, but I'd advise taking them to a real battery shop if you're going to that amount of labour. Good luck. Jim Watts Paradigm Shift C&C 35 Mk III Victoria, BC On 16 July 2017 at 15:37, Tom Buscaglia via CnC-List <cnc-list@cnc-list.com> wrote: I stressed out m house bank pretty bad by leaving the frig on and the D.C. On, but the shore power, and this the charger, came lose on the boat due t my sloppy connecting. It was discovered after 3 days or so. I am concerned that the batteries may be damaged beyond use...just like the set of house batteries these replaced, after two full days at anchor with the frig runningh. Very lagged with them all still wired into the boat are around 12.5. 13.2 when the engine is running and 13.7 with the charger on. Some questions for the list's cumulative wisdom... Do I need to disconnect the battery to accurately assess its health? Are these voltages in an appropriate rage? thx Tom BuscagliaS/V Alera 1990 C&C 37+/40Vashon WAP 206.463.9200C 305.409.3660 _______________________________________________ This list is supported by the generous donations of our members. If you wish to make a contribution to offset our costs, please go to: https://www.paypal.me/stumurray All Contributions are greatly appreciated!
_______________________________________________ This list is supported by the generous donations of our members. If you wish to make a contribution to offset our costs, please go to: https://www.paypal.me/stumurray All Contributions are greatly appreciated!
