Who knows if instruments of the ExdIIBT4 rating require a safety barrier?
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As the title suggests, there is currently a DCS project for a polyether plant, and all instruments used are of the ExdIIBT4 rating. Is it necessary to install safety barriers in the control room as well?
Flame-proof types do not require a safety barrier; only intrinsically safe types need one!
This is the flameproof code for intrinsically safe devices; a safety barrier is not required. Safety barriers are only used in intrinsically safe instrument circuits.
Yes, it’s not necessary to add it; only ia requires it.
Reply to 4# hjbjl: Is it not necessary for ib? Please explain
For flameproof types, no safety barrier is needed; for intrinsically safe types, one is required, and the same applies to IB types as well!
Explosion-proof instruments do not require a safety barrier; only intrinsically safe instruments need one
If the field instruments only have intrinsically safe explosion-proof certification, then a safety barrier must be used. If the field instrument has passed intrinsically safe certification as well as explosion-proof certification, it can be used without a safety barrier. (With one exception: when the field instrument has two wiring compartments, one certified for intrinsically safe use and the other for explosion protection; in such cases, a safety barrier is still required.)
From the code you provided, it appears to be of the intrinsically safe type; therefore, no safety barrier is needed. A safety barrier is required only for devices that are intrinsically unsafe. The code in this case is E*a or E*b
Flameproof type, used in IIB areas; no additional installation required.