1771-CFM

Overview

1771-CFM is a Configurable Flowmeter Module from Allen-Bradley designed for accurate frequency and flow signal measurement in PLC-5 control systems. It supports multiple flowmeter types and programmable counting modes.

Input and Channel Configuration

• Number of Input Channels: 4

• Module Location: 1771-A1B, -A2B, -A3B, -A3B1, -A4B (Series A & B) I/O chassis; 1771-AM1/-AM2 I/O chassis with power supply

• Inputs per Channel: Gate input used in Totalizer and Nonresettable Totalizer modes

• Flowmeter Input Voltage: 5–30V DC (TTL compatible), 50mV–30V AC (magnetic pickup), compatible with Bently 3300 5mm & 8mm proximity pickups

• Flowmeter Input Impedance: 5KΩ ±30% resistive

• Gate (G0–G3) Voltage: 5–12V DC and 12–30V DC

• Gate (G0–G3) Current: 22mA maximum

Performance and Frequency

• Maximum Count Value: 0–9,999,999 (programmable)

• BTW Processing Time (worst case): 5.5ms (on configuration change)

• Module Scan Time: 1.3–5ms (depending on configuration and frequency)

• Maximum Input Frequency: 100kHz @ flowmeter input (overrange at 100kHz); 100kHz @ gate input

Output Characteristics

• Number of Outputs: 4

• Maximum Output Off-State Leakage Current: <300µA @ 30V DC

• Maximum On-State Voltage Drop: 0.6Ω × current

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