[Milsurplus] Modern Power Supply

[Mike Feher]

Well, for anyone wanting to get real serious, I have about 8 24volt 80
amp transformers. Should be adequate for most Mil gear. - Mike

 
Mike B. Feher
EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960
908-902-3831 - cell
 
 

-----Original Message-----
From: milsurplus-bounces at mailman.qth.net
[mailto:milsurplus-bounces at mailman.qth.net] On Behalf Of David Stinson
Sent: Thursday, February 22, 2007 11:01 PM
To: Milsurplus at mailman.qth.net
Subject: Re: [Milsurplus] Modern Power Supply

As a user of switcher supplys for mil radios, a couple of tips:

Most (not all) of these multi-voltage switchers *must* have a load on
every
output for it to work properly.  Minimum load is usually an amp or two.
If you leave it unloaded, see it it "pumps" (ramp up volts too high,
shut
down, do it again several times a second). If it does, you need to load
the
output.
For a typical load of 24 volts at an amp, you need around
24 ohms at more than 25 watts across the output all the time.
Calculate for the other outputs as well.
These things make a good heater.
If you're not going to use the 12 or 5 volt outputs,
you should disable them by removing them from their rack mounting.

Also, they don't like surge current.  If you're going to try running
dynos,
hang some big "computer grade" caps
(50 to 200,000 mfd or more) across the output to take the starting
surge.
If you don't, it will shut down on you every time.

p.s. $65 seems pretty stiff for these surplus supplies.
Maybe I'm just cheap ;-).


______________________________________________________________
Milsurplus mailing list
Home: http://mailman.qth.net/mailman/listinfo/milsurplus
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Milsurplus at mailman.qth.net