[ARC5] A pair of questions

[Bob Camp]

Hi

A pair of Mean Well RSP-1000-27 supplies running in parallel would do the trick if
you are going the swisher route. You can go bigger if you need to. They let you run
as many as 4 in parallel at one time. Each one puts out 37A at 27V. They will adjust 
up to 30V on the output. 

The switchers have the advantage of efficiency. At 100% efficiency you will have 
17.5A at 120V going into your setup.  That will squeeze into a 20A circuit (sort of ….)
A pure linear supply (as opposed to a pre-switcher / post linear) is not going to be
very efficient…..

A 140A 20V transformer and a 200A diode bridge would be another approach. Put
a few big high current  caps on the output and you have a supply. That sort of idea 
has been my approach over the years …. Not much regulation, but lots of current. 

Bob


> On Nov 13, 2017, at 5:05 PM, Scott Robinson <spr at earthlink.net> wrote:
> 
> A switcher rated for 75A might be cheaper, but of course it can be a source of RF noise.
> /scott
> 
> On 11/13/17 12:57 PM, Michael Hanz wrote:
>> On 11/13/2017 3:06 PM, Craig wrote:
>>> A couple of questions for the collective knowledge. I'm starting to look for a decent bench power supply for my gear. I've gone thru the books and added up the power requirements for running the planed system and all was well until I hit the power requirements for the SCR-269. Holy smokes, it really jumped the current needs....The dyamotors for the -269 really drive up the requirements. A PE-89 requires a 20 amp circuit and it's alternate, a PE-109 requires a 35 amp circuit.
>>> 
>>> So, anyone have a suggestion for a bench supply that will provide 75 amps at 24 VDC, and not break the bank? Batteries are out due to the needs for out gassing control and space.
>> You don't really need a 75 amp power supply per se for those loads. What you need is a power supply that will provide a surge rating of perhaps 75 amps to start the dynamotors, which means it will have to be a brute force supply.  The only regulated model I know of is the PP-1104*.  It puts out 50 amps at 28vdc 24/7, but has easily started a big 400Hz inverter in no-load testing that was rated at 100 amps input at full power out.  It has an 8" fan in the rear, so it does have some blower noise, but it's not obtrusive.
>>> Second question.. Anyone have a copy of the manual for the RC-55 Test Set that they would be willing to copy, or know where I could find one? As the chance of me finding the pieces to assemble one, at an affordable price is probably very close to zero, I'd like to build my own replica. Copying expenses would be covered.
>> I've never seen a manual for the RC-55.  However, I think just about everything you'll need is in my documentation section.  See http://aafradio.org/docs/Command_Set_Test.html _and_ the link to the RC-55 page at http://aafradio.org/docs/ARC_Test_Sets.html
>>            73,
>>  - Mike  KC4TOS
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