GA-02.029-EN-03-05-2018 gAVC 1200 Installation Manual.docx
GA-02.029-EN-03-05-2018 rev.03
Page 19 of 31
Bad equalization between the gAVC earth connection and the earth connection of the connected equipment
may result in disrupted communication.
5.6 Earthing and connection of conducting cable screens
Earth connection:
gAVC 1200 N/NP mounted in zone 0 require 3 independent earth connections.
Inside the gAVC you will find 2 earth connection terminals. 2 parallel wires 1.5 mm
2
will normally be required
(refer to local regulations).
The third earth connection must be made in one of two ways:
Either use the pressure sensor cable screen. In the gAVC the screen must be connected under the cable
mounting bracket. The metal housing of the pressure sensor must be mounted on earth connected gas
tube
Or use a wire of same dimension as stated above. But inside the gAVC connect the earth wire to screw
terminal marked GND in the section for pressure sensor.
gAVC and gas pipe/meter may have to be connected with an earth connection, depending on actual
installation conditions.
Precautions must be taken to avoid static electricity. Do not mount gAVC on electrically isolated base.
At mounting the gAVC: First connect the earth wires and then the rest of wires afterwards.
At dismounting the gAVC: Keep one of the earth wires connected until all the other wires and sensors are
disconnected. Then disconnect the earth wire and the gAVC can be taken down.
Connection of conducting cable screens leaving hazardous area
Where screen is required the screen shall be electrically connected to earth at one point, normally at the
non-hazardous area end of the circuit. This requirement is to avoid the possibility of the screen carrying a
possibly incentive level of circulating current in the event that there are local differences in earth potential
between one end of the of the circuit and the other.
In the publications mentioned in chapter 5.2 you find the further requirements and recommendations.