The transmitter operates with the housing, either floating or grounded. However, the extra noise in floating systems affects many types of readout devices. If the signal appears noisy or erratic, grounding the transmitter at a single point may solve the problem.
You can reduce electrostatic current in the leads induced by electromagnetic interference by shielding. Shielding carries the current to the ground and away from the leads and electronics. If the transmitter end of the shield is adequately grounded to the transmitter and the transmitter is properly grounded to the earth ground, very minimal current enters the transmitter.
If the ends of the shield are left ungrounded, a voltage is created between the shield and the transmitter housing, and between the shield and earth at the element end. The transmitter may not be able to compensate for this voltage, causing it to lose communication and/or generate an alarm. Instead of the shield carrying the current away from the transmitter, the current flows through the sensor leads and into the transmitter circuitry where it interferes with circuit operation.
Each accelerometer contains a drain wire that is connected to the sensor shield. This wire should be connected to the internal grounding screw attached to the housing near the terminal block.
Ground the transmitter in accordance with local, national, and international installation codes. You can ground the transmitter through the process connection, the internal case grounding terminal, or the external grounding terminal.