Devices with a voltage of 48 VDC have been previously seen. 24 VDC instruments are widely used these days. Is it because 24 VDC consumes very less power, so 48 VDC is no longer used?
Now on the market there are LED indicators that consume less power than the previous ones. Will 24 VDC become obsolete in the future, replaced by 12 VDC / 5 VDC?
Industries use standard 24 volts DC with 4-20 mA loop current for powering the major number of instruments connected to PLC or DCS systems. Practically it is not possible to replace the existing systems to any other voltage levels without a new investment.
The usage of 48 V DC is not a common practice. We only see this voltage from some manufacturers only. It has very less installation base when compared with 24 volts DC.
Now-a-days the industry is upgrading to digital devices like foundation fieldbus, profibus, etc. You can expect the change in this direction i.e. DIGITAL.
New industries are focused on wireless devices wherever possible to reduce the price.