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8-6. Panel wiring at non-hazardous area
(Guide for the Installation of Explosion-proofed Electrical Equipment 9.6.6.7)
In the event of wiring intrinsically safe circuit inside the instrument panel in
non-hazardous area, be sure to follow the instructions below.
In general, the panel must have a relay box for external wiring of this relay box should be
installed inside the panel.
(1)
When both intrinsically safe equipment and other electrical equipment need to be
mounted in a same panel, the position of these equipments, relay box and wiring
method must be well arranged so that it will not cause power cross and induction.
(2) In general, the panel must have a relay box so that cables for intrinsically safe circuit
and other circuit can be properly relayed inside the panel. The energized part must be
protected by a cover so that it may not cause power cross with non-intrinsically safe
circuit.
In addition, in order to prevent miss-wiring, the relay box should use something light
blue for intrinsically safe circuit so that everyone can find it easily and quickly.
8-7. Other wiring
See the “Guide for the Installation of Explosion-proofed Electrical Equipment 9.6.”
8-8. Grounding
(1)Transducer
E terminal of the intrinsically safe terminal P
，
N, E and G terminal of power source
terminal G, 0V, 100-110V, 200-220V are not connected inside the transducer.
[Purpose of each E terminal]
E terminal of the intrinsically safe side P, N, E
Purpose: To maintain intrinsically safe explosion-proof structure
…..Class A or higher level grounding is required.
G terminal of power source side G, 0V, 100V, 200-220V
Purpose: To prevent electrical shock (in accordance with the Technical
Standard for Electrical Equipment)
……Transducer’s G
terminal is connected to the case. Terminal
should be grounded as required.
Grounding terminal G of safety barrier side
……The terminal is connected to the case. Terminal should be
grounded as required.
