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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: somewhereinusa on February 04, 2013, 02:15:12 PM

Title: Battery cables
Post by: somewhereinusa on February 04, 2013, 02:15:12 PM
Started assembling my new battery cables and ran into a problem.  I bought 4/0 cable(clearly marked AWG 4/0) and 4/0 crimp on lugs. Started first end, and the lug is no where near big enough to go over the cable. I thought well darn,  they sent the wrong lugs. Looked up the specs,4/0 cable end is supposed to be .548 mine measure .548. I looked up cable specs, 4/0 is supposed to be .460, that would fit very nicely. My cable measures, on average about .600. Since I wouldn't be making the cable less than 4/0 is it permissible to cut enough strands off to fit into the lug?  I can do that but what a PIA for 20 ends.  What other options?

On another electrical question I have a new ammeter and shunt. It says to put the shunt on the negative side. I have found a number of wiring diagrams with it on the positive side. Is there any reason I can't put it on the positive side?

Thanks,
Dick
Title: Re: Battery cables
Post by: Len Silva on February 04, 2013, 02:48:28 PM
If you are using welding cable, you need the correct size welding cable lugs.  Electrically, the cable is the same size but because of the fine stranding, it is a bit bigger physically.  If you go to a major supplier website (T&B, AMP, Burndy, etc. they will have that info.
Title: Re: Battery cables
Post by: AndyG on February 04, 2013, 03:13:35 PM
Allow me to ask a dumb question.  Are you stripping back the rubber insulation before trying to slip the lug on the end if it?  If you are stripping the insulation back and the lugs still don't fit i suggest that you get bigger lugs instead of cutting away some of the strands.  It will be easier and you will have the best connection possible.  You can't have battery cables that are to big or connections that are to good when trying to start these big engines.
Title: Re: Battery cables
Post by: Ralph7 on February 04, 2013, 03:16:35 PM
   The shunt needs to be on the NEG, it measures all amp draw/charge.  I uae a SOC  (state of charge) meter  a ( TM-2025-RV) and it uses the shunt that way.
  Also with the Magnum 2000W /100A charger.
  This is on my house battery bank.    
Title: Re: Battery cables
Post by: FloridaCliff on February 04, 2013, 06:11:04 PM
Hey Somewhere,

Exactly what Len sad.  I buy a lot lugs outside of  "bus world" and that is a common mistake when ordering the lugs. (blame your salesman)

It totally depends on the size and amount of strands in the wire.

As Andy said, its a hundred times easier to get the right lug..

Best of luck,

Cliff

Title: Re: Battery cables
Post by: luvrbus on February 04, 2013, 06:21:42 PM
I bought some heavy wall fusion lugs from www.remybattery.com (http://www.remybattery.com) I know people here like the crimp style but I don't care much for the crimp style
Title: Re: Battery cables
Post by: belfert on February 04, 2013, 07:04:56 PM
Highly stranded welding cable or marine battery cable will be larger than other 4/0 wire/cable.  My friend brought over some 4/0 terminals once designed for use with typical stranded wire and they didn't fit my 4/0 welding cable.  I had to get the right terminals from a local electronics distributor.
Title: Re: Battery cables
Post by: gus on February 05, 2013, 12:34:48 PM
Getting wrong or defective parts is no longer the exception, it is, unfortunately, very common.

It took me a while to accept this but now I routinely check to make sure I have the right stuff.