Leisure Battery advice (1 Viewer)

Forestboy

LIFE MEMBER
Jul 31, 2007
5,023
8,338
Forest of Dean
Funster No
46
MH
A Class Hymer B694 tag
Exp
9
Thinking of adding another battery to my leisure batteries but not totally confident about wiring it correctly. I have 2 batteries one under each seat and plenty of room behind each seat to fit an extra battery in a compartment. My question is what is the correct way to wire the extra battery into the bank without doing any damage.
Thanks :thumb::thumb:
 

peter marshall

Free Member
Mar 5, 2009
2,466
1,704
Cleveleys,Lancashire
Funster No
5,822
MH
Low Line
Exp
9 Years
Hi
Posative to Posative, and Negative to Negative , + to + & - to -, inline fuse on the Pos if possible, I have done 3 without no prob, others like a fuse to be sure but the batteries have a inline fuse fitted already, you may also need a vent point if the additional Bat has a breather tube. Pete :thumb:
 
OP
OP
Forestboy

Forestboy

LIFE MEMBER
Jul 31, 2007
5,023
8,338
Forest of Dean
Funster No
46
MH
A Class Hymer B694 tag
Exp
9
Thanks Pete :thumb: thats what I thought.

Just to clarify I only need to connect to one of the existing batteries not both. One would be easy both would be difficult as on opposite sides of van and don't want cables running everywhere.

Subscribers  do not see these advertisements

 
Apr 27, 2008
11,842
14,065
Eastbourne East Sussex
Funster No
2,327
MH
Hymer low profile
Exp
Since 1972
One Battery is all you need to connect to. Make sure the fuse is appropriate for what you use though; don't use a 10A fuse if you run an inverter as it will just blow every time you use it. Unless the connecting lead is short then fit a suitable fuse in the positive line at both ends.
 
OP
OP
Forestboy

Forestboy

LIFE MEMBER
Jul 31, 2007
5,023
8,338
Forest of Dean
Funster No
46
MH
A Class Hymer B694 tag
Exp
9
Thats sorted then Thanks Guys:thumb::thumb:

Subscribers  do not see these advertisements

 
Jan 28, 2008
10,111
18,365
Dovercourt, Harwich, UK
Funster No
1,353
MH
Renalt burstner
Exp
7 years campers before that
are both your existing batteries for the leisure side or is one the vehicle battery ? if so you have to connect the new battery to the leisure battery asuming thats the side you want the extra capacity
 

hilldweller

LIFE MEMBER
Dec 5, 2008
605
36,109
Macclesfield
Funster No
5,089
MH
Zilch Mk1
Exp
From Aug 2007
Broken Link Removed

But dangerously incomplete. All you have to imagine is any of that red line rubbing through the insulation to earth ( the blue line ). You could have in excess of 3000 amps flowing. That means a BIG BANG and/or fire.

So think fuses. Look at revised picture. If the red wire at point 2 was shorted to earth then current flows from two directions. From Batts 1+2+3 and from Batt 4. So you would need a fuse at point 1 and 3 to be safe. 50A would be a good guess.
 

Attachments

  • battery_bank_parallel2.jpg
    battery_bank_parallel2.jpg
    41.6 KB · Views: 66
OP
OP
Forestboy

Forestboy

LIFE MEMBER
Jul 31, 2007
5,023
8,338
Forest of Dean
Funster No
46
MH
A Class Hymer B694 tag
Exp
9
are both your existing batteries for the leisure side or is one the vehicle battery ? if so you have to connect the new battery to the leisure battery asuming thats the side you want the extra capacity

Yes both batts are leisure

But dangerously incomplete. All you have to imagine is any of that red line rubbing through the insulation to earth ( the blue line ). You could have in excess of 3000 amps flowing. That means a BIG BANG and/or fire.

So think fuses. Look at revised picture. If the red wire at point 2 was shorted to earth then current flows from two directions. From Batts 1+2+3 and from Batt 4. So you would need a fuse at point 1 and 3 to be safe. 50A would be a good guess.

I was planning on fitting a 50amp fuse in the positive lead on the new connection, would that be correct?

Subscribers  do not see these advertisements

 

TheBig1

LIFE MEMBER
Nov 27, 2011
17,600
43,041
Dorset
Funster No
19,048
MH
A class
Exp
many many years! since I was a kid
Yes both batts are leisure



I was planning on fitting a 50amp fuse in the positive lead on the new connection, would that be correct?


50amp sounds overkill for most applications. whatever you use, ensure that the weakest cable attached can take the current and fuse accordingly
 

hilldweller

LIFE MEMBER
Dec 5, 2008
605
36,109
Macclesfield
Funster No
5,089
MH
Zilch Mk1
Exp
From Aug 2007
I was planning on fitting a 50amp fuse in the positive lead on the new connection, would that be correct?

If in doubt fit one right next to each battery.

But if the wire is short and safe just fit one "just in case" something goes pear shaped within the battery.
 

pappajohn

LIFE MEMBER
Aug 26, 2007
43,301
49,289
Dark side of the moon
Funster No
172
Exp
Since 2005
Brian is correct of course, but if all the leads are long and wandering then put a fuse at both ends of ALL live/pos wires.

more work and expense but if ANY of the live leads touch earth and aren't fused then there's nothing to stop a possible fire situation from the unprotected end.

Subscribers  do not see these advertisements

 
OP
OP
Forestboy

Forestboy

LIFE MEMBER
Jul 31, 2007
5,023
8,338
Forest of Dean
Funster No
46
MH
A Class Hymer B694 tag
Exp
9
Brian is correct of course, but if all the leads are long and wandering then put a fuse at both ends of ALL live/pos wires.

more work and expense but if ANY of the live leads touch earth and aren't fused then there's nothing to stop a possible fire situation from the unprotected end.

The leads will be about 3ft long as the batt will be directly behind passenger seat in a cupboard.
 

haganap

LIFE MEMBER
Dec 5, 2007
12,754
26,415
planet earth
Funster No
974
MH
Niesman+Bischoff 79e
Exp
I'm an oldbie MH number 10
Rory,

Bring it to Chester, ill do it for ya :Smile:

Its simple stuff, but as Brian points out,

I fuse every one, and ignore Jim's picture,,,,,,

You should never use them batteries, there crap :ROFLMAO:

But, get yourself a good BM1 like in the picture, :thumb:

Ive got one and they are fascinating :whatthe::whatthe:

Every time Jan turns a light on, you will be looking at it. :whatthe::whatthe:
 

Join us or log in to post a reply.

To join in you must be a member of MotorhomeFun

Join MotorhomeFun

Join us, it quick and easy!

Log in

Already a member? Log in here.

Latest journal entries

Funsters who are viewing this thread

Back
Top