Bob Ammerman wrote:
> I would strongly recommend that the original poster see what happens
> if he treats the sensor as a current loop device:
>
> Connect +24V to +ve lead of sensor
> Connect -ve lead of sensor to load resistor (250 ohms or so)
> Connect other lead of load resistor to ground
> Scope signal across load resistor
>
> If the device is indeed 4-20ma current loop, then the signal should
> swing somewhere between 1 and 5 volts.

Before he does that, I'd see what it does completely open in case its just a
magnet with a coil wrapped around it.  Connect the sensor to the scope probe
directly with no supply or anything else.  Does he get the 50mV signal now
when waving a screw driver nearby?  If so, you probably don't want to try
applying power.

If all else fails, he could check the datasheet.


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