Proline Promag 53 FOUNDATION Fieldbus
18 Endress+Hauser
<
Potential equalisation with shielding grounded at both ends
Fig. 7: Examples of the connection of potential equalisation lines
1 = distributor/T-box
2 = Promag 53 bus devices for hazardous area
3 = bus termination: R = 90...100 Ω, C = 0...2.2 µF
4 = fieldbus power supply variant 4a
4a = shielding connected via capacitor
5 = fieldbus power supply variant 5a
5a = potential equalisation line led out
Variant 4/4a:
With capacitive grounding of the shielding in the safe area the potential equalisation line
does not need to be led out of the safe area.
Use small capacitors (e.g. 1 nF, 1500 V, dielectric strength, ceramic). The total capaci-
tance connected at the shielding must not exceed 10 nF.
Variant 5/5a:
Potential equalisation line is led out of the safe area.
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F06-5xxxxxZZ-04-xx-xx-xx-000