Is it better for on-site instruments to be powered by 220V AC or 24V DC?
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Is it better to power field instruments with 220V AC or 24V DC? With the increasing use of intrinsically safe instruments, more and more instruments are being designed for two-wire operation. So, for instruments used in non-hazardous areas, does your organization use 220V AC or 24V DC for power supply (such as electromagnetic flowmeters, mass flowmeters, etc.)? What are the advantages and disadvantages? Everyone is welcome to share their thoughts!
24V DC sources are generally configured in a redundant manner, which makes them safer, especially for powering field instruments in SIS systems. DC low voltage is safe and easy to maintain. Direct current is less affected by voltage fluctuations (indirectly). The downside is that the cables cost a bit more, 2.5 square millimeters compared to 1.5 square millimeters. 24 is the power source that keeps the instrument alive, and the solenoid valve relies on it as well.
It is safe at 24V, and the wiring and related aspects are also safe, but the capacity of the switching power supply needs to be taken into consideration. For 220V systems, a switching power supply is not necessary; it’s cheaper, but care must be taken to ensure safety when making connections on-site
It is safe at 24V, and the wiring and related aspects are also safe, but the capacity of the switching power supply needs to be taken into consideration. For 220V systems, a switching power supply is not necessary; it’s cheaper, but care must be taken to ensure safety when making connections on-site
24V DC is the better choice; it’s also safer for people... The expert on the second floor explained it very clearly
24V DC applications are becoming increasingly common
I don’t understand what you mean by the need for a switching power supply for 24V; I have a 2-wire instrument that is powered internally, with the signal and power lines being the same one. A wire with a cross-sectional area of 1.5 mm² will also work, as long as the distance is no more than 500 meters.
In my humble opinion, 24 volts is better.
It’s related to the instruments. If the instrument is in an explosion-proof enclosure, any power supply will work. If it’s the cavity in this case, it can only be connected to 24V. For safety reasons, 24V is generally recommended.
24V DC is the preferred option, as it is safe for both humans and instruments. What was said by those in other floors is clear enough; however, in some cases, high-power instruments still require a 220V power supply