Can NAMUR proximity switches be powered by 24V?
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Hello everyone, these are the NAMUR proximity switches provided by the on-site equipment manufacturers. The input voltage is 8.2V, and an isolation barrier is required to convert 24V to 8.2V. If there is no isolation barrier, can the proximity switch be directly powered by 24V from the DCS? Can the proximity switch work properly? Thank you
No. NAMUR is not a standard signal; the function of your safety barrier is not only to supply power but also to convert signals, and without a safety barrier, it is no longer an intrinsically safe circuit
Designing without a proper understanding leads to making mistakes.
No, connecting it directly will burn out the fuse or the circuit. A safety barrier must be added
This type of signal is not really used very often. Besides, it’s not cheap either; it’s highly unlikely to be widely adopted
Unless it is necessary to design a cost-effective solution, avoid using this type of close-proximity design; it is costly and has many failure points.
Stop it, NAMUR signals aren’t used very often – are we still living in the 1970s? NAMUR is now the most commonly used type of feedback switch in chemical industries, especially in the petrochemical sector. It features intrinsically safe operation, and only NAMUR feedback switches can achieve intrinsically safe functionality.
No intrinsically safe circuit is required; can it be connected to 24V? As long as the on/off function works properly, that’s fine
The DCS itself operates at 24V, so it won’t get damaged; the question is whether a proximity switch can also be used with 24V
If you’re not using NAMUR, it means you still have a long way to go in the pitfalls ahead