Can intrinsically safe and flameproof instruments be used together?
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The explosion protection zone is Zone 2; there are both intrinsically safe and flameproof instruments within the same device – is this in compliance with the standards and specifications? Can they still be used together?
Instruments can of course be used interchangeably. Intrinsic safety and flameproof cables cannot be placed directly in the same junction box.
Inertial gas instruments and explosion-proof instruments can certainly be used together; the difference lies in the methods of achieving explosion protection. Inertial gas instruments ensure their explosion-proof safety through circuit design, with strict requirements for the internal circuits – specifically, the distributed capacitance of the circuits and wires must not exceed three set limits. Additionally, the power consumption must not exceed 5W, and there are also several standards regarding distributed inductance. For more details, refer to 3836.1–3836.4. The explosion-proof mechanism of flameproof instruments relies on mechanical sealing, taking into account the issue of explosion-proof gaps; however, generally speaking, the overall cost of using flameproof instruments is much lower than that of intrinsically safe instruments
As long as it meets the explosion-proof requirements for hazardous areas, it is acceptable; of course, meeting higher standards than those required for explosion protection is also fine.
Sure, without using a cable tray or a cabinet