Emerson Rosemount 3814 - Page 55

• Digital output 2A is based on Digital output 2A content (Frequency Output 2
Validity and Flow Direction)
• Digital output 2B is based on Digital output 2B content (Frequency Output 2
Validity and Flow Direction)
Mode options
• Open Collector (requires external excitation supply voltage and pull-up
resistor)
• TTL (internally powered by the meter 0-5 VDC signal)
Channel B Phase options
• Lag forward, Lead reverse (Phase B lags Phase A while reporting forward flow,
leads Phase A while reporting reverse flow)
• Lead forward, Lag reverse (Phase B leads Phase A while reporting forward
flow, lags Phase A while reporting reverse flow)
Phase A and Phase B output (based on flow direction)
• Reverse flow - output only reports flow in the reverse direction. For frequency
outputs, Phase B of the output is 90 degrees out of phase with Phase A.
• Forward flow - output only reports flow in the forward direction. For frequency
outputs, Phase B of the output is 90 degrees out of phase with Phase A.
• Absolute - output reports flow in both directions. For frequency outputs, Phase
B of the output is 90 degrees out of phase with Phase A.
• Bi-directional - output reports flow on Phase A only in the forward direction
and on Phase B only in the reverse direction.
Maximum frequency for the frequency outputs
• 1000 Hz
• 5000 Hz
Table 3-5: Frequency/Digital Outputs possible configurations
Frequency/Digital output Source configuration
Frequency /Digital Output 1
Frequency /Digital Output 2
Frequency /Digital Output 3
Frequency /Digital Output4
Frequency /Digital Output 5
Frequency /Digital Output 6
• Frequency output 1A
• Frequency output 1B
• Digital output 1A
• Digital output 1B
• Frequency output 2A
• Frequency output 2B
• Digital output 2A
• Digital output 2B
Installation manual Electrical Installation
00825-0100-3814 January 2023
Rosemount 3814 Liquid Ultrasonic Flow Meter 55