[mikeeastman]

Here are the cables I made up to run from battery bank (200 amphrs @ 24v) to PI battery buss (or the "Battery Bomb' as Dave calls it ). Just sent them off for Cryoing along with ICs, speaker cables and battery interconnects. Should have the bomb and cables by next week.




24' of #4 with PE gold plated connecters.

[dBe]

Mike, those look awesome!  This is gonna be quite an experiment in insane battery power goodness 

Let's see:

3 outputs at 14.8V @ 15A for the amps
1 output at 12V @ 7.5A for the NAS
1 output at 12V @ 7.5A for the Mac Mini
1 output at 5V@ 7.5A
4 outputs dual voltage 12V & 5V for later

Yep, that ought to cover it, methinks.

Too much fun.   

Dave 

[mikeeastman]

Battery Bomb just arrived, here are pics.






Will post impression in a couple day after I get it hooked up played with.

[cheap-Jack]

Hi.

Here are the cables I made up to run from battery bank (200 amphrs @ 24v) to PI battery buss.

24' of #4 with PE gold plated connecters.

Please note AWG#4 (0.204" copper diameter) can only handle up to 60A full duty cycle. For 200A an hour duty cycle, you need to get up to 3/0 gauge (0.409" copper diameter) each cable to avoid heavy voltage drop.

Larger currrent bigger gauge size of copper cable needed.

c-J

[HAL]

For the last battery project, I used MCM250 gauge copper and copper grounding bars.  Very low loss with 4 - 12vdc / 100ah batteries wired in parallel.  Not very flexible to work with.  The batteries are AGM's so ok to use inside.  The local electrical supply store lent me the crimper to use when I bought the lugs. 

[rajacat]

Hi.
Please note AWG#4 (0.204" copper diameter) can only handle up to 60A full duty cycle. For 200A an hour duty cycle, you need to get up to 3/0 gauge (0.409" copper diameter) each cable to avoid heavy voltage drop.

  edit:  Larger currrent bigger gauge size of copper cable needed.

c-J

It depends on how long the cable run is too. As long as the run isn't too long, it seems to me that AWG#4 should be adequate. I doubt that he'll be running gear that'll draw anything close to a steady 60A. It may be a 200A battery but the wire needs to be for the anticipated load. No need to account for starter surges.

Whoops , I just noticed that it's a 24' run. I might have to recalculate.

[mikeeastman]

battery bank with cryoed interconnects, nuts and power cables.That space to right is were the big brother battery bank will go in a couple of weeks, when I move my house solar system into its new home. 1350 amphrs @24v.





System top to bottom; Battery Buss, classD amp w/Dodd tube buffer(on same chassis) Apogee Ensemble Dac, Spatial modded mini w/ PI audio Macsandwitch, Red Wine Isabellina Dac




My max draw will be 30-40 amps so lose shouldn't be any more than 2%, with batt voltage between 28v-24.8 at lowest the #4 should work.

[jtwrace]

Those do NOT look like sealed batteries.  That's a HUGE 

[cheap-Jack]

Hi.

My max draw will be 30-40 amps so lose shouldn't be any more than 2%, with batt voltage between 28v-24.8 at lowest the #4 should work.

If the load is only 30-40A, #4 lead should be OK.

Those do NOT look like sealed batteries.  That's a HUGE 

No, they are acid batteries which I'd never use INDOOR. They smell bad.

I'd surely use sealed acid type.

c-J

[mikeeastman]

There not, there golf cart batteries, but their in my solar equipment room, in a sealed box, vented to the out side (same box that will house my solar system batteries). But your right in any other situation it would be bad.

[HAL]

Very cool!

[rajacat]

Nice setup! I'd like to go all DC too but I'd have trouble parting with my rebuilt/modded Heathkit monoblocks. Presently, I use a 12V battery,capacitor buffered with 5V converter to power my Bolder SB3 to excellent effect. I thought that the sound quality was at least equal to using a top line Acopian linear PS that has an extremely low ripple spec. (0.25 mV RMS) If anything the battery powered SB3 is more transparent. 
Next I'll be looking to build the Dodd battery pre.

[mikeeastman]

Here is pic of inside of Battery Bomb.

[mikeeastman]

Got my battery charger mounted. 40 amp @ 24volts.

[JDUBS]

Nice!  What gauge wire is used?  Looks like a mixture?

-Jim

Here is pic of inside of Battery Bomb.

[mikeeastman]

 I don't know on buss maybe Dave will jump in.