1771-A3B

The Allen-Bradley 1771-A3B is an I/O chassis for 1771 I/O modules. The 1771 PLC-5 system is a modular system that needs a 1771 I/O chassis to allow installation of various modules. Communication between I/O modules and either the processor module or the I/O adapter module is provided by the backplane. The 1771-A3B chassis has 12 I/O slots. It has a dimension of 13.53 x 19.0 x 8.5 in. and weighs 19.1 lbs. For installation in a 1771 PLC-5 system, it uses a 19-inch rack mounting or Back-panel mounting method with adequate spacing and open enclosure. The chassis backplane has a power supply of 8A at 5V DC. The 1771-A3B chassis has a universal configuration for chassis mounting and system design because of its consistent design. 1771 I/O modules are small, flexible, cost-effective and provides a complete range of digital, analog, and intelligent I/O modules for various applications. I/O modules come with wiring arms and remote termination panels, eliminating the need to for disconnecting the wire to replace the module. For troubleshooting and diagnostics status indicators are present on the front of modules. For future expansion, it can be easily replaced with a larger chassis. It is intended for use in an industrial environment with a 0 - 60 °C (32 - 140 °F) operating temperature, 5-95 % noncondensing relative humidity, and a 30g operating shock.

The Allen-Bradley 1771-A3B is a universal I/O chassis. This hardware belongs to the 1771 Programmable Logic Controller (PLC) product range. It is mainly used to provide installation location of 1771 I/O modules. It provides the module inter-connectivity to the backplane as well as installation area of individual module 1771 wiring arms.

The 1771-A3B comes with twelve (12) I/O slots and supports direct installation to the enclosure subpanel through the mounting tables provided with the hardware. Alternatively, this chassis may also be mounted to a 19 inch rack. This module is available in two (2) series, specifically, Series A and B.

The 1771-A3B delivers a maximum backplane current of 24 Amperes. It has a physical measurement of 483 x 339 x 221 millimeters or 19.0 x 13.35 x 8.7 inches and weighs 5.9 kilograms or 13 pounds. It is certified for installation and use in application areas identified as Class 1, Division 2, Groups A, B, C and D. It has an operating temperature of 0 to 60 degrees Celsius or 32 to 140 degrees Fahrenheit and a storage temperature of -40 to 85 degrees Celsius or -40 to 185 degrees Fahrenheit with a relative humidity of 5 - 95 %, non-condensing. When mounting this I/O chassis, use ¼-20 (M6 x 10) mounting bolts. Keep vibration and shock to the host panel maintained, not exceeding 2g at 10-500 Hertz and 15g, respectively. Additionally, appropriate installation clearance must be followed when installing this hardware to allow natural air cooling and adequate working space. Required mounting clearance are 102 millimeters (4 inches), distance between a major component and enclosure sides; 153 millimeters (6 inches) vertical separation between major component and the chassis; 102 millimeters (4 inches) minimum horizontal separation.