ALLEN BRADLEY 1762-IF4

Overview

ALLEN BRADLEY 1762-IF4 is a MicroLogix 4-point current and voltage analog input module for the Allen-Bradley MicroLogix 1200 and compatible 1762 expansion I/O systems. The module provides four differential bipolar analog input channels for connecting field transmitters, sensors, potentiometers, transducers and other analog measurement devices to a MicroLogix PLC. It supports configurable voltage and current input ranges, channel diagnostics, LED status indication and isolated I/O wiring for industrial control cabinets. The 1762-IF4 is part of the Bulletin 1762 MicroLogix expansion I/O family and remains an active mature Rockwell Automation product, widely used as a replacement I/O spare in existing MicroLogix control installations.

Features

ALLEN BRADLEY 1762-IF4 provides four differential bipolar analog inputs. The analog normal operating range covers voltage from -10 to 10 VDC and current from 4 to 20 mA, while the full-scale analog ranges cover voltage -10.5 to 10.5 VDC and current -21 to 21 mA. Supported voltage and current configurations include -10 to +10 VDC, 0 to 5 VDC, 0 to 10 VDC, 1 to 5 VDC, 0 to 20 mA and 4 to 20 mA. The A/D converter uses a successive-approximation architecture, with one converter shared across the four multiplexed channels. Resolution is 15 bit for bipolar inputs.

The module reports channel diagnostics through bit reporting, detecting over-range, under-range or open-circuit conditions on analog inputs. Common mode rejection is greater than 55 dB at 50 and 60 Hz, with a common mode voltage range of -27 to 27 V. Voltage terminal input impedance is 200 kΩ. Input protection includes -30 V voltage input protection and -32 mA current input protection. Input update time is selectable at typical values of 130, 250, 290, 450 or 530 ms. Overall accuracy is typically ±0.32 percent of full scale from -20 to 65 degrees Celsius, and ±0.24 percent of full scale at 25 degrees Celsius; non-linearity is ±0.12 percent of full scale, and repeatability is -0.12 to 0.12 percent.

The 1762-IF4 uses screw terminal electrical connection and includes a module power LED that indicates when power is applied. Input and output groups are isolated from the system with 30 V AC and 30 V DC rated working voltage, using IEC Class 2 reinforced insulation type tested at 500 V AC or 707 V DC for one minute. Bus current draw is a maximum of 40 mA at 5 VDC and 50 mA at 24 VDC. The module supports hazardous location Class I, Division 2 Groups A, B, C and D, and includes ESD and industrial immunity protection for cabinet-mounted PLC installations.

Specs

Product series: Allen-Bradley Bulletin 1762 MicroLogix expansion I/O Model: ALLEN BRADLEY 1762-IF4 Type: 4-channel current and voltage analog input module Compatible controllers: MicroLogix 1200 and compatible MicroLogix 1762 expansion I/O systems Number of inputs: 4 differential bipolar channels Input types: Voltage and current analog inputs Normal operating voltage range: -10 to 10 VDC Normal operating current range: 4 to 20 mA Full-scale voltage range: -10.5 to 10.5 VDC Full-scale current range: -21 to 21 mA Configurable ranges: -10 to +10 VDC, 0 to 5 VDC, 0 to 10 VDC, 1 to 5 VDC, 0 to 20 mA, 4 to 20 mA A/D converter: Successive approximation, multiplexed across channels Resolution: 15 bit bipolar Input impedance: Voltage terminal 200 kΩ Common mode rejection: Greater than 55 dB at 50 and 60 Hz Common mode voltage range: -27 to 27 V Input update time: Selectable typical 130, 250, 290, 450, 530 ms Overall accuracy: ±0.32 percent full scale at -20 to 65 degrees Celsius; ±0.24 percent full scale at 25 degrees Celsius Non-linearity: ±0.12 percent full scale Repeatability: -0.12 to 0.12 percent Protection: Voltage input protection -30 V; current input protection -32 mA Diagnostics: Over-range, under-range or open-circuit condition by bit reporting Connection: Screw terminal Status indication: Module power LED I/O isolation: 30 V AC / 30 V DC rated working voltage, IEC Class 2 reinforced insulation Bus current draw: Maximum 40 mA at 5 VDC; 50 mA at 24 VDC Dimensions: Width 40 mm, height 90 mm, depth 87 mm Shipping weight: Approximately 240 g with carton Operating temperature: -20 to 65 degrees Celsius Storage temperature: -40 degrees Celsius lower range Operating humidity: 5 to 95 percent non-condensing Operating altitude: 2000 m Hazardous location: Class I, Division 2 Groups A, B, C, D Country of origin: Malaysia Product status: Active mature Rockwell Automation MicroLogix analog I/O module

Principle

ALLEN BRADLEY 1762-IF4 operates as a signal conditioning and analog-to-digital interface between field analog devices and the MicroLogix PLC. Each analog channel receives a voltage or current signal from a transmitter, sensor or transducer. The module conditions and multiplexes the channel signals into a shared successive-approximation A/D converter, which converts the analog level into a digital value for the PLC processor. The MicroLogix controller reads the digital input data, scales it according to the configured range, and uses the value for monitoring, PID control, alarms or data logging.

Channel diagnostics monitor the input for over-range, under-range or open-circuit faults and report the condition through status bits. Isolation separates the field I/O group from the controller system, reducing ground-loop noise and protecting the PLC cabinet electronics. The power LED indicates module power, while bus current is drawn from the controller or base power supply during normal operation. Shielded cable such as Belden 8761 is recommended for analog signal wiring to reduce industrial electrical noise.

Applications

ALLEN BRADLEY 1762-IF4 is used in MicroLogix PLC systems that need analog measurement from voltage or current field devices. It fits packaging machines, production lines, conveyors, mixers, pumps, fans, hydraulic and pneumatic monitoring, temperature conditioning, pressure and level measurement, flow monitoring, material handling, test benches, machine tools, food and beverage equipment, water and wastewater, utilities, chemical processing, sugar mill and pulp mill automation, and other discrete or process control panels. In existing MicroLogix installations originally equipped with the 1762-IF4, the module serves as a direct replacement analog input spare, compatible with the original 1762 base mounting, screw wiring and PLC I/O configuration.