24v instrument power supply issue
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This post was last edited by hfrs on 2016-6-15 at 16:46. 500 meters, 24vdc, for electromagnetic flowmeters and mass flowmeters; powered by 2x1.5 cables. Has anyone used this? Do I need to replace the 2x2.5 cable?
I’ve used it; the voltage rose to 17.5 volts, and then I started to get headaches. There are so many instruments that it’s not possible to get rid of any of them.
We have never used 2x2.5 cables for power supply; we use 2x1.5 cables for that purpose
A 2x2.5 cable should be used.
I’ve used it; a 1.5 value works fine for such a long distance, but the interference is quite severe. It’s better to use 2.5, as there is signal attenuation and voltage drop
500 meters is quite far; the voltage drop is too large, so it’s better to use a thicker wire. 2x2.5
It is recommended to use 2×2.5. There is a common rule regarding this; I’ve forgotten whether it’s a standard requirement or one of our own regulations. It seems that for distances over 300 meters, a 2.5 gauge cable must be used, so we decide to use 2.5 gauge cables for all our designs, even though the signal cables only require a 1.0 gauge
It is recommended to use 2*2.5, to facilitate maintenance and error diagnosis of the instruments in the future
The distance is too great; it’s best to calculate the voltage drop, and it could be changed to 220V.
A 4-20 mA signal uses 1.5, while mass flow meters are powered by AC; DC power results in too long distances and significant voltage drop.