Shop OBEX P1 Docs P2 Docs Learn Events
Proper cable shield grounding practice — Parallax Forums

Proper cable shield grounding practice

Don MDon M Posts: 1,647
edited 2009-04-01 22:29 in Accessories
I hope someone can answer this.

Using a Dallas temp sensor though a shielded 3 conductor cable (DC+, DC- & Data) inside a machine. The cable will run parrallel to other low voltage AC & DC cables. For the remaining end of the cable where the sensor is located it is mounted inside of a small refrigeration system.

Should the shield be grounded only on one end such as the end where it connects to a microprocessor board?

Presently it is grounded at the beginning where it connects to the micro board and then the other end is tied to the DC- at the temp sensor end along with the DC- conductor in the cable. Doesn't seem quite right to me but that is why I am asking. I think the shield should remain disconnected from the DC- at the sensor. By the way, the DC- and the micro board ground are at the same potential.

Can anyone help here?

Thanks.

Comments

  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2009-04-01 22:29
    Yes, ground the shield at one end only. Otherwise, you will have current running through your shield, which will compromise its effectiveness.

    -Phil
Sign In or Register to comment.