Paul Saccani > wrote:
>Bernd Felsche wrote:

>>I also have a hand-held, digital 'scope. One of the clamp meters has
>>peak-hold -- I'd forgotten about that. It might do the trick.
>>
>>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".
--
/"\ Bernd Felsche - Innovative Reckoning, Perth, Western Australia
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