Battery filling

[hammerdown]

Am I lucky, I've had my NAPA batteries for 5+ yrs and have put water in them only 3 times.....I check semi monthly and they don't need water......

 

[kfrancis]

Not really sure Criss...over the years I have just come to a flat fee agreement with edesur on my monthly bill. They tried to bill me based on the size of the house and not actual usage...even when I as out of the country while my parents were alive. I do remember that before I installed the reduction unit my charging time was a few hours longer than after the installation.

kFrancisco

 

[donluis99]

This guy says NO.
I would say "NO" to cross tying a battery bank.

If all is working well, then cross ties do nothing (as you have confirmed with your current measurements).

The only time cross tying would "help" is when there is an open cell or electrical connection--And that comes with lots of issues:

If the cross tie "works", then the bypassed failed cell means that other series cell(s) will be in danger of being over discharged (i.e., if you have two parallel strings, that would mean a 50% discharge of the "whole" string would be a 100% discharge of the cell carrying the bypassed current). Cross tie avoids this

And, the whole issue of fusing/breakers... Normally, with paralleled battery strings, you only need one breaker/fuse per string for over current protection. With cross tied batteries, in theory each cross tie would need fusing/breakers too (nobody is going to do that).

Lastly, it makes checking the battery bank for faults (open/shorted cells, bad cabling, etc.) that much more difficult. You have to measure cross tie current to make sure it is zero, and if it is not, then you have to figure out why it is not zero (probably disconnecting the cross tie for debugging). Makes voltage measurements across cells/battery meaningless--If you measure 12.x volts across a cross tied battery, which battery is supplying that voltage (are other batteries low/failed?).you can still check individual batteries and individual
cell with no issues at all

I cannot think of a reason for cross tying that would give any real advantages--And lots of real disadvantages.
after cross tying my present set of of trojan 205's, installed June 2009, previous battery sets only lasted 40 - 42 months, and I have to fill with h2o less often,
And, like Marc/Cariboocoot finds when he makes a black/white answer, I will be awaiting somebody telling me I am wrong and there is/are real advantages for doing this (just none that I can think of).

-Bill "been there, done that" B.

Bro I ain't gonna tell you your wrong, I just do not agree with you at all and neither do the electrical engineers
at Xantrex / Trace and so far my experiance fully vetts thier advice out as GOOD!

g'luck

http://dr1.com/forums/north-coast/104843-inverter-expert.html

 

[donluis99]

And, the whole issue of fusing/breakers... Normally, with paralleled battery strings, you only need one breaker/fuse per string for over current protection. With cross tied batteries, in theory each cross tie would need fusing/breakers too (nobody is going to do that). I guess your talking about paralleled series
battery banks, indiviual breaker per series bank is a good idea and probably correct to do, so what your only talking about what, maybe 2 breakers (2 banks @ 48VDC /16 batteries) or possibly 3 breakers (3 banks @ 48VDC /24 batteries) etc. I think that an additional breaker for every 8 batteries is a relative cheap protection and should be done REGARDLESS if the banks are cross ties or not and if you can install US$3,200.00 of batteries you probably can afford to spend another US$125.00 each on 2 additional breakers for an added measure of protection

g'luck