Path: utzoo!attcan!uunet!cadnetix.COM!cadnetix!rusty
From: rusty@cadnetix.COM (Rusty Carruth)
Newsgroups: sci.electronics
Subject: Re: additional info on switch problem
Message-ID: <8523@cadnetix.COM>
Date: 19 Jun 89 18:25:07 GMT
References: <4100@tekig4.LEN.TEK.COM>
Sender: news@cadnetix.COM
Reply-To: rusty@cadnetix.COM (Rusty Carruth)
Organization: Cadnetix Corp.,  Boulder, CO
Lines: 55

In article <4100@tekig4.LEN.TEK.COM> jime@tekig3.LEN.TEK.COM (James W. Edwards) writes:
>I posted a description of a switching control problem a few days ago.
>I have gotten quite a few responses.  Several people have asked for
>additional info.  Also, I have been informed that without this additional
>detail that I would probably get overdesigned solutions.  To refresh
>your memory I have included the original request along with the additional
>detail.
>
>
>>I have a problem for you electronics wizards.  I would like to control
>>the DC power being supplied to two loads as shown in the following diagram:
>>
>>  +--[Load 1]-------------[CP1]-------------+-------+
>>  |                                         |       |
>>  |                                         |       DC
>>  +--[Load 2]-------------[CP2]-------------+      POWER
>>  |                                                 |
>>  |                                                 |
>>  |                                                 |
>>  +-------------------------------------------------+
>>						     |
...etc..., you will need this info to make sense out of my reply

Quick question:  Why not just use a choke and a relay?  Like so:

cp<x> ==  ____()()()()()()()____
                                |
                               \~
                                \
                                 \o-----------
                         ______
                               )
                               )
                               )
                         ______)

where ()()... is the choke, and the other mess is the relay, use
NO contacts if you want relay fail to leave loads on.

I await all the reasons I know will be forthcoming to explain why this
won't work :-).

Oh, I suppose we WILL need to know if the load is purely resistive or not,
won't we?

(and finding the proper value of the choke is "left as an exercise for
the reader" :-), translated, I'm too lazy right now to find the info
I'd need to figure it out for you, and besides, I don't have all
the info I'd need in order to figure it out anyway.... :-).

Good luck.
---------- 
Rusty Carruth  UUCP:{uunet,boulder}!cadnetix!rusty  DOMAIN: rusty@cadnetix.com
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