Xantrex and Interstate Batteries....

[ken&ellen]

17 months ago I replaced my Trojan batteries with Interstate batteries. Last month I noticed that two of the six batteries had started to boil over. After cleaning the compartment I tested the batteries....3 of the six would not hold a charge. I took them back to the Interstate folks and they pro-rated them off of list price....which put them above the purchase price from the wholesaler. I bought one to complete a 4 battery bank. All was good for a week. Now I have another battery that will not take a charge. The Xantrex alarm went off...prior to this point the system went through the charging stages and all read outs were consistant with " system normal ".
These batteries are supposed to be 36 month waranty. The bulk charge is around 14.2 and 13.5 at float. I am done with Interstate, but now I am concerned about the system.
Xantrex is a RV3000 and it is less than 4 years old. All settings were basically factory defaults. Your thoughts. Ken

[stevet903]

Boiling over sounds like it is overcharging. What kind of batteries are they? (gel, flooded, AGM?) Do you have a model number for them?

Here's a table for some of the Interstate deep cycle batteries:

http://www.batteries-faq.com/activekb/questions.php?questionid=1

Does your inverter have a temperature probe for the batteries?

Steve

[ken&ellen]

Steve, They are flooded deep cycle ( golf cart ) = Trojan T-105 ( according to Interstate ). Yes, the temp probe is reading within a degree or two of ambient. I watered the batteries on a regular schedule and was enjoying good performance up until a month ago. My load for DC is low...water pump, air compressor for commode, couple of lights. I have read the operators manual and the charging voltages indicated on the screen are consistant with the manual as well as the chart you included . I do agree with you that usually batteries boil out at high charge rates. During the past summer the temps here were in the high 90's to low 100's daily....I left the compartments open when the coach was in the barn. I am going to sit down and re-read all the data as well as check all connections on the Xantrex.

[stevet903]

Do your batteries charge from the engine when it is running? Maybe the issue is the alternator and not the inverter/charger? The regulator could be bad and keeping the charging voltage way up..... Also check your battery cables, some could be corroded internally and not allow the full charging current to go to the battery that it is connected to, and could cause the others to overcharge. These types of connections will usually be warm or hot to the touch when charging or under a heavy load. They will also show a voltage drop if you take a meter and measure from each end of the cable while under load (could be from .5 to 2V depending on the load, etc)

Steve

[ken&ellen]

Steve, It is interesting that you mention the alternator, since I just read on another site that overcharging could be caused when bus is running and not by inverter/charging system. I will add that to my list of systems to check. I had checked the cables....which are a made from welding cable ( usually 37 or more strands )....and I got good readings....but will re-check. Thanks for your input. Ken

[ken&ellen]

Alternator is putting out 15.5 volts on dash gaugle...way over the name plate voltage. The regulator is a $38 dollar item and the tool to test it is several hundred dollars. I think I will just get the replacement voltage regulator.

[stevet903]

Sounds like a good place to start, post and let us know how it works out!!
Steve

[Jon Wehrenberg]

As a general comment regarding batteries they must be installed in sets of equal batteries. I always insist on the same date codes, and if one should fail prematurely, unfortunately the entire set must be replaced.

Steve nailed it when he pointed out the alternator can be a contributor, but so can other less obvious factors. Clearfly the inverter charging protocol has to be correct for the battery type. But one overlooked situation is some inverters always go into bulk charge rate when power is removed and restored regardless of battery charge condition. When my bus is parked in the garage I always maintain power to it, and leave a voltmeter connected or available at the batteries to do a quick check of battery voltage. I also periodically do a check of both inverters to assure myself the charge voltages for bulk, absorption and float are per the battery manufacturers recommendations.

Batteries are among the items on my coach I change based on my schedule due to age and not condition. I aim for a 5 year change date on batteries just because a failure on the road creates more grief than it is worth. So far that schedule has worked well with frequent monitoring throughout their life. I never charge the chassis batteries except as needed and they can go several months between trips or charges. The house batteries are always being charged except when dry camping, and on those occasions I will never let them fall below 12.3 (24.6) before manually starting the generator. I do not use autostart. At the current cost of batteries it just makes a lot of sense to treat them properly.