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Topic: Battery bus bar and switch ratings (Read 235 times) previous topic - next topic

Battery bus bar and switch ratings

I want to replace the engine/start batteries in my coach, after an approx. 10 year life span they need to be retired.
I will go with wet cells again. Group 34, 800 cca, 1000ca. Costco has them for $99 each with core turn in.

I intend to update the cabling while I'm at it.

What kind of rating do I need for a Buss Bar with the 3 batteries cabled in parallel?
I would also like to add a Blue Sea on/off switch, what rating would I need?

Thanks for your advice.
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.

Re: Battery bus bar and switch ratings

Reply #1 –
Lon & Cheryl,

Buss Bar: we made our own pos & neg buss bar. Using pos & neg military battery terminals each of the three batteries. We drilled solid metal bars to match the military terminal bolt holes and connect cables & buss bar with long bolts.  Top Post Battery Terminals End for Marine Car Boat RV Vehicles Negative and...

On/Off Switch: We found our coach had a dedicated pos battery cable from battery direct to starter, with no other cables on starter. This cable does not need to be switched as it will not have any current draw other than when cranking engine. Without a switch, the starter is guaranteed max current for cranking engine.

We put a battery switch on other start battery bank cables, which does draw anywhere near the starter cable current, so any amperage cut-off switch will work.

Re: Battery bus bar and switch ratings

Reply #2 –
I put the 500 Amp Blue Sea in my coach as I have a 160 amp alternator.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Battery bus bar and switch ratings

Reply #3 –
Quote from: oldguy –
I put the 500 Amp Blue Sea in my coach as I have a 160 amp alternator.

Good for everything except start batteries to starter.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020
 

Re: Battery bus bar and switch ratings

Reply #4 –
The starter current doesn't go through the Blue Sea, just charging current unless it is used as
a boost switch and being 500 amp it is 300 more than the standard boost switch.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport