[Test-Equipment] Ideas ?

Sat, 06 Sep 2003 23:10:40 +0000

   How much current is flowing through the relay's coil?
   How much current is flowing through the relay's contacts?
Are we dealing with ac or dc?

   A hall device could be fed into an OP-Amp for some pretty
weak current monitoring.  (glue or clamp the sensor on a wire)
   Have you considered gluing paper targets (half white,
half black) on the relay armatures and positioning a photo
emitter/detector next to the relay?
   Have you considered gluing a mirror or silvered metal dot
on the relay armatures and positioning a photo emitter/detector
over the relays?
(this could be done through fiber optic fibers if you wish)
   Have you thought about placing a coil or hall sensor on the
bolt or nut under the relay on the other side of the mounting
plate/chassis at the center of the coil's axis?
   Can you place a flat wound coil 20 or 30 wraps of wire under
each relay and sense the magnetic field? (longer bolt/s might
be needed)

   Tell us more, be more specific and we will help where we can.

> 1. Sense the presence or not of a current (DC) and switch a 1v to 24V
> current to the data logger. (+V = Bit 1 ON - 0V = Bit 0 OFF)

> 2. Allow non-contact or non-intrusion connection to the cable.

> 4. Be economic enough to allow several hundred to be used, the idea being to
> attach them and leave in place. Or at least 38 per relay room at a time on a
> semi-permanent bases.

> 5. Themselves NOT to introduce any AC or any interference with the cables
> they attach to.
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