DrDrreeeaaa
Electrical
Has anyone ever connected a HART-only device (i.e. without 4-20mA) onto a HART AI module?
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HART-only device connected to HART AI channel
- Thread starter DrDrreeeaaa
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No. It's not a functional concept.
The FSK modulated HART signal is superimposed on the current signal.
HART infers a current signal as well. For point-to-point, it's a 4-20mA signal. For multidrop, it's 4mA fixed. But there's always a current signal.
The FSK modulated HART signal is superimposed on the current signal.
HART infers a current signal as well. For point-to-point, it's a 4-20mA signal. For multidrop, it's 4mA fixed. But there's always a current signal.
Why not just make a dummy current loop using fixed resistors then add the FSK Hart signal in series. The total loop resistance could be about 2k with the HART imposed over a fraction of that. You might have to experiment a little, perhaps some small capacitors to couple the signal across the resistance.
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