Q4: What is the difference between the 3185 and the 3186?
Answer: Both the 3185 and 3186 are loop powered isolators, but they are powered differently.
The 3185 is energized by an active 4-20 mA loop connected to the input terminals, and provides an active output.
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The 3186 is energized by an active 4-20 mA loop connected to the output terminals, and provides an excitation source on the input terminals for the purpose of energizing a 2-wire transmitter.
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