Inductive sensor shielding

[spumco]

Dear PMDX,

I have inductive proximity sensors I'm connecting to a PMDX-126.  The cables are too short and I've purchased some 3-conductor foil-shielded cable to extend the run to the 126.

Question - the original cables are not shielded.  How would you suggest terminating the shielding (there's a drain wire available) on the cable extensions?  The easiest way appears to be installing a screw terminal on the enclosure backplane adjacent to the 126 board and connecting the drain wire from the various sensors to this (new) earth terminal.

Or - leave it floating and don't worry about the shielding?

Or - connect all the drain wires to a conductor and terminate the conductor at some other ground point?  Such as the star ground block inside the enclosure (adds about 10"-12" from the proposed backplane terminal location).

Or - is there some location on the 126 that is suitable for connecting the shield drain?  I suspect not, but figured I'd ask.

Thanks,
Spumco
Thanks

[Steve Stallings]

Our recommendation would be to connect all the drain wires together with the ground
wires from the sensors, and then connect these to the GND terminals of J11 or J12 on
the PMDX-126.

The GND terminals on J11 and J12 are typically also connected to a ground on the
control cabinet, but in some situations you may get better results if it is not connected
to the control cabinet. Combining the drain wires with each other before running a
single wire to the GND on the PMDX-126 is OK.

[spumco]

Steve,

Thanks a ton.  Is there something I need to do to connect J11 or J12 to the control cabinet, or are they grounded through the board mounts?

[Steve Stallings]

No connection is made by the board mounting holes. If you want the
GND of the PMDX-126 connected to your control cabinet you must
add a wire to do so.

Do not connect the PCgnd from J1 through J6 to the control cabinet
ground.

[spumco]

Awesome - thanks again for the guidance.