What is the difference between the grounding terminal inside the pressure transmitter junction box and the grounding terminal on the enclosure?
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This post was last edited by wangduo1122 on 2022-1-21 at 11:52. What is the difference between the grounding terminal inside the pressure transmitter junction box and the grounding terminal on the enclosure? Under what circumstances do these two terminals need to be connected, for example on a gas pipeline?
Most transmitters nowadays are two-wire field instruments, with the grounding terminals inside and outside the instrument being identical and connected through a conductor. The external grounding terminals facilitate the simultaneous connection of multiple external grounding network wires, while the internal grounding terminals facilitate the connection of the shield grounding wires for signal/power cables. The figure below shows Yokogawa Electric’s instructions regarding the instrument grounding terminal for pressure transmitters.
This post was last edited by GeniusTTUV on 2022-7-4 18:07:111111
The external grounding terminal is connected to the grounding grid only in special situations, such as areas with frequent lightning strikes. The internal grounding terminal is used to connect the shield wire; either the cable’s shield wire is connected to this terminal or to the grounding terminal at the other end of the cable, such as the working grounding terminal of the DCS cabinet, to ensure that one end is grounded.