Bernd Felsche > wrote:
>Paul Saccani > wrote:
>>Bernd Felsche wrote:

>>>Well, it'd tell me the current through the circuit. Which isn't
>>>necessarily the same current that'll be drawn when the long wire is
>>>replaced with a short one and a transistor switch.

>>...and now we get to what you are really up to. No doubt with a
>>MOSFET in mind. Don't neglect the back EMF, and the transient inrush
>>current could be significant.

>That's my main concern. The inrush and other transients.

>>You could always buy a COTS solid state relay - for you to engineer as
>>good a solution from parts for the hostile environment it can expect
>>to live in, is something that will cost you a good deal more than the
>>$23 for a COTS 80 A 0-100VDC solid state relay.

>BTS50055-1TMB is designed for the environment, provides useful
>feedback and therefore diagnostics (at about $6). I need to
>determine the solenoid current to allow for an adequate "overkill".

In retrospect (?), I can prototype just the power circuit to make
sure that it doesn't release the magic smoke. Although testing would
only be for the conditions under which I'm testing ... so need to
make them as bad as possible.
--
/"\ Bernd Felsche - Innovative Reckoning, Perth, Western Australia
\ / ASCII ribbon campaign | For every complex problem there is an
X against HTML mail | answer that is clear, simple, and wrong.
/ \ and postings | --HL Mencken