[Milsurplus] DC power help rerquest please..

[David Ross]

Mac & the gang -


Herschel McCullough wrote:
> 
> I have a friend who has sorta gotten the surplus bug.. but I'm not sure he is all their.  He went and bought some dang Tank , Helicopter Search Light..  the thing is 24 vdc powered and the lamp is 2.2 kw..  so this dog is needing at the minimum 140Amps DC @ 24vdc and he has involved me by asking where he can get that much current, besides a battery supply..
> So I'm asking you guys for any help or suggestions please ..  thanx  mac/mc
> 


  Those searchlights are brutes but a 426U-2 will run 'em.  The 426U-2
is a Collins PS, rated 28VDC @ 125A, designed by Collins but built by
Ault.  Used to be that murphyjunk had them, don't know if he has any
left.

  The 426U-2 is the size of a 618T (1ATR package) and weighs about 100
lbs.  It is rated to run from 3 phase power but does fine off plainjane
220 with a good solid center tap ground.  The 426U-2 just rectifies line
voltage (no internal isolation), so it must either have a very solid &
reliable ground connection or be run through a heavy duty isolation
transformer with a hefty center tap on the output side.

  I use a 426U-2 here to run a TRC-75 benchtest setup -  a PP-2352 makes
400~ 3PH power for the TRC-75.  It all runs from a 220 <-> 220 isolation
transformer with no complaints.  In this pic:
http://www.hypertools.com/power_pallet.jpg
the 426U-2 is on the left, then a 426T-1 400~ 1PH inverter, then the
PP-2352 400~ 3PH inverter -  the isolation transformer is in the rear. 
The rack & air plenum assembly is from a TRC-136 shelter.


73
Dave Ross    N7EPI    ross@hypertools.com