150 with 8 gauge battery cables?

[mcgyver]

I have a new 1000amp marine battery, but only had battery cables off a 20-30hp engine (I assume about 8 gauge) othewr than the wire getting hot with cranking, would it also affect how many amps get to the starter? I have a very slow crank speed and think I need to upgrage to a 4 agw battery cables.

 

[Don S]

Re: 150 with 8 gauge battery cables?

think I need to upgrage to a 4 agw battery cables.

Of course you need bigger battery cables. Length is also a factor. What "150" are you talking about?

 

[fixnfly]

Re: 150 with 8 gauge battery cables?



Hope this helps.

 

[bruceb58]

Re: 150 with 8 gauge battery cables?

View attachment 189594

Hope this helps.

So what's the allowed voltage drop with that chart. Chart means nothing unless you know that.

 

[fixnfly]

Re: 150 with 8 gauge battery cables?

This table was calculated assuming, a .36 voltage drop for starting and
a .44 voltage drop for charging, a maximum operating temperature of 150F. A larger
wire can be used to decrease the voltage drop or to operate at a higher temperature.
These numbers will give you a "ball park" idea.

 

[bruceb58]

Re: 150 with 8 gauge battery cables?

This table was calculated assuming, a .36 voltage drop for starting and
a .44 voltage drop for charging, a maximum operating temperature of 150F. A larger
wire can be used to decrease the voltage drop or to operate at a higher temperature.
These numbers will give you a "ball park" idea.

These charts are different based on % voltage drop. For starting, you can get away with a lot more percent voltage drop. They are usually 5%, 10%, 15% or 20%.

 

[bruceb58]

Re: 150 with 8 gauge battery cables?

To the OP, use a DVM and measure from the positve battery post to the starter. You should not have much more than 0.5v measured. Do the same for the negative side. Should be identical. If they are not identical, one of them has a resistive connection.