③
Screen
④
Cable junction box
⑤
External power supply SELV U
DC
= 24 V
⑥
Indicator
⑦
Potential equalization
5.2.1
Potential equalization
In order to avoid possible balancing currents between the individual conductive system
components, a potential equalization must be installed in potentially explosive areas.
The terminal
must be connected to the potential equalization system and installed and
earthed in accordance with local regulations (see also schematic diagram).
Schematic diagram
(1)
(2)
(1)
(1)
(2) (3)
(6)
(6)
(A)
(4)
(4)
(4)
(A)
(A)
(A)
(A)
(A) (A)
(E)
(5)
(B)
(1)
(1)
(1)
(1)
(1)
(A)
(A)
(A)
(A)
1
2
4
3
3
①
Ex area
②
no ex area (secure area)
③
Load cell
④
Cable junction box
Pos.
Component
Cross-section
(1)
Conductor for additional potential equalization
≥4.0 mm
2
Cu
(2)
Potential equalization conductor
≥6.0 mm
2
Cu
(3)
Potential equalization conductor
≥10.0 mm
2
Cu
(4)
Main potential equalization conductor
≥10.0 mm
2
Cu
(5)
Ground conductor
≥10.0 mm
2
Cu
(6)
Load cell override
≥10.0 mm
2
Cu
5 Installation
Intrinsically safe load Cell interfaces PR 1626/60, ../61
Minebea Intec
EN-13
