An ultrasonic level transmitter output is stuck at 22mA, triggering a high-level alarm on the SCADA screen, even though the tank is completely empty. What does the 22mA signal indicate?
Answers
AThe transmitter has lost 24V power entirely
BA direct short circuit between the 4-20mA wires
CA programmed fail-safe fault condition (e.g., loss of echo) configured to drive the output high
DThe tank is overflowing and the sensor is submerged
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