The temperature transmitter is connected to Hart, but the device cannot be found
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The E+H temperature transmitter requires a new display head; the range is to be adjusted using Hart in the calibration laboratory, but the device cannot be found. The 24V power supply is working fine – does it mean a 250-ohm resistor needs to be connected as well? Please give some guidance, thank you\ud83d\ude4f
Yes, an external resistor is required; it would be easier if there were a tester available
Yes, a resistor (load) needs to be added
Yes, a standard resistor needs to be added, or a temperature safety gate can also be installed
What kind of power supply are you using? If it’s a switching power supply, 475 volts won’t work for connection; you can use a process verifier to provide 24 volts, and then use 475 volts for the connection.
Based on my personal experience, using Emerson’s own HART handheld device, it can usually be connected directly from the control room, as the host computer itself already incurs a load when performing detections； However, domestic HART handheld devices have poorer stability, and a 250Ω resistor must be connected in series. Then, connect the ends of the hand controller to the ends of the resistor, or to the ends of the instrument – either way is fine.
Bro, a single-effect unit must be equipped with a resistor; even the Emerson 475, which is an imported model, requires one as well