Overview
The Allen-Bradley 1771-OFE1/B is a PLC-5 series analog output module engineered for industrial process control and automation applications. This module delivers voltage signals used to power modulating devices including control valves, adjustable frequency AC drives, dampers, positioners, and louvers. The 1771-OFE1 is single slot and directly installs to a Bulletin 1771 I/O chassis.
Key Features
- Four individually isolated voltage output channels ±10 VDC
- Converts 12-bit binary or 4-digit BCD (binary-coded decimal) values to analog signals using 4 outputs
- Output ranges include +1 to +5 VDC; -10 to +10 VDC and 0 to +10 VDC
- Built-in overload protection against short circuit load conditions
- 1500V optoelectrical isolation protects the system from overvoltage situations
Technical Specifications
12-bit resolution with backplane current draw of 1.50 Amperes and DAC maximum settling time of 0.8 ms for a resistive load. Internal scan rate is 8.0 ms for every channel utilizing BCD data and scaling and 1.6 ms for all channels using binary data and no scaling. Accuracy is ±0.1% of full scale; ±1/2 Least Significant Digit (LSD) when operating in BCD mode and ±1/2 Least Significant Bit (LSB) when configured in Binary mode.
Typical Applications
The module can be used as a signal source for data loggers, splitters, totalizers, panel meters, and single loop controllers. Peripheral devices including motor speed controllers, valve positioners, signal converters, or recorders can be connected to the output.
Compatibility & Replacements
The 1771-OFE1/B is designed exclusively for Bulletin 1771 I/O chassis systems running PLC-5 processors. Power dissipation is 7.9 Watts and thermal dissipation is 26.9 BTU/hr. Operating temperature range is 32 to 140 °C with operating shock of 30 g and vibration of 2g at 10–500 Hz. This module represents the industry standard for legacy PLC-5 analog output control and integrates seamlessly into existing 1771-based systems.
