Can such an intrinsically safe wiring method meet the explosion-proof requirements?
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The wiring method currently in use is as follows: intrinsically safe control buttons are installed in non-explosion-proof button boxes (outside the safety zone) + intrinsically safe safety barriers (within the safety zone) + PLCs, etc. (also within the safety zone). During external safety inspections, experts suggested that the non-explosion-proof button boxes should be replaced with explosion-proof ones. Since there are many control buttons, I would like to ask whether my previous intrinsically safe wiring method can meet the explosion-proof requirements If it can be achieved, what verifications are needed? I would be very grateful if experienced folks could give me some advice.
Personally, I don’t think an explosion-proof button box is necessary, as the device is intrinsically safe – the energy that reaches the site has already been reduced to a safe level. So why is it necessary to use explosion protection at the site?
Is this really an expert in instrumentation? :lol
Hello, friend. There are terminal blocks in the wiring box on site; will this affect explosion protection?
Hey, could you give some guidance on the content on floor 4?
Hey, could you give me some guidance on the content on the fourth floor? Thanks
1. First, you need to understand the meanings of intrinsically safe and flameproof in explosion protection (I think you don’t understand them). Looking at the pictures, these switches seem to be part of circuits powered by 220VAC alternating current. If that is the case, it is necessary to consider a control box with an explosion-proof design corresponding to that level. If there is no 220V AC in the box, only dry contacts and 24VDC are present. You can look below: 2. If the circuit meets the intrinsically safe requirements (the entire circuit, from the switch and wires to the safety barrier, meets these requirements), the terminal block does not affect the intrinsically safe performance criteria.
I agree with the experts’ opinion: it is not possible for all of your circuits to be intrinsically safe circuits, as this represents a serious violation of safety and instrumentation standards.
I agree with the views from the 7th and 8th floors below; it seems there is no isolation here – no isolation barriers or safety fences in sight! Therefore, boxes that meet the corresponding explosion-proof requirements must be used on site; otherwise, serious problems will occur.
Only dry contacts and DC24V are available
This junction box is located in the hazardous area; it features only dry contacts and DC24V power. The safety barrier is placed inside the PLC control box in the safe area.