> -----Original Message-----
> From: Vasile Surducan [SMTP:vasile@L30.ITIM-CJ.RO]
> Sent: Monday, January 29, 2001 10:43 AM
> To:   PICLIST@MITVMA.MIT.EDU
> Subject:      Re: [PIC]: 2.5KW Load
>
> > According to Peter L Peres this relay will also be hot after 30
> minutes...Is
> > it a better option to look at bidirectional power MOSFET modules then?
> >
>   I have doubts you can't find a good relay. However you may use a trick,
> power the relay coil through one of his normal closed contacts, on the
> normal open one put a resistor to V+. When the relay is on his coil will
> be powered with just a fraction on V+ enough to keep relay closed but less
> with about 30% thermal stress. Much cheaper than a MOSFET modules.
>
> Vasile
>
This assumes the relay armature has enough momentum to actually reach the
normally open contact after the normally closed contact has broken.  If not
you will have a nice buzzer!  A better method may be to just use the
normally closed contacts with a resistor wired accross them.  At least the
coil will still have some current after the contacts have broken.

Mike

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