400 amp Niehoff N1602 alternator setup question

[WAGNUM]

I'm switching out my 200amp alt to a 400amp alt. Anyone know if you "have to" run a second set of positive and negative battery cables to the 400 amp alternator? The 400 amp alt has two pos and two neg posts on it. I know you have to connect a jumper cable from the rear posts to the front posts, pos to pos and neg to neg. But is it critical to run another separate pos and separate neg cable from the alt back down to the batteries? Any chance I can just run the jumpers from the rear posts to the front posts and call it good? (or will my stock cables get too hot if it ever pulls more than 200 amps?) Anyone out there have pics of their setup?
Thanks,
Wags

 

[juanprado]

All I can say is eat your Wheaties. That looks like a beast and that last pic implies you need ky to get that puppy in there....

All the best

 

[Wire Fox]

Huh...that does fill out all of that extra space nicely, doesn't it? Out of curiosity, why the upgrade from 200 to 400A? Do you have a massive new running load on your HMMWV that the 200A couldn't cover?

About the cabling...the cables chosen for the 200A alternator are pretty close to the limit for 200A going through a hot engine bay. No way in **** will it handle 400A for more than the shortest of current spikes. Run the second set of leads to maintain the full capacity you need.

 

[someoldmoose]

400 A, in a HMMWV ? Did YOU procure one of them that "heat ray" thingys ? Or just banging about Ten 12" subs ? Wow. But yeah, run cables. In fact 3 ought ga. cables would NOT be Overkill. Our fire apparatus uses that alt and we have a bird's nest coming off of it. All the "old" halogen rotating lights draw over 240amps when all lit and the cables get HOT.

 

[mechanicjim]

C.E.Niehoff has the installation instructions for the unit on their website http://www.ceniehoff.com/Documents/Ctrl_Hyperlink/II0059A_uid121020091153181.pdf
as to "Have to" no just run the interconnect cables and run the one cable back to battery B+ and Ground, as a side note yes make sure the cable you have will carry the current you expect to see in the system.

 

[WAGNUM]

Yep, after getting all kinds of wrong info you're right. (Not that I doubted you...) Talked with engineering at Niehoff this am. Confirmed what you said. Told me they had to keep the outer diameter of the alternator a specific dimension so that's why they had to put outer terminals and use interconnect cables to "join" both 200 amp halves together to get the 400amp output. As long as my cables can handle the amps I'm good to go!