Allen-Bradley 1771-OP AC Output Module 4-channel

Product Overview

The Allen-Bradley 1771-OP is a 4-channel protected AC output module for PLC-5 1771 I/O systems. It provides 120V AC output switching with protected output circuitry, conformal coating, and status indicators for reliable control of AC-powered industrial devices in legacy automation installations.

Key Specifications

• Output Channels: 4 AC outputs
• Voltage Category: 120V AC
• AC Operating Range: 92–138V AC
• Frequency Range: 47–63 Hz
• Max Continuous Current per Output: 2 A
• Max Current per Module: 6 A
• Backplane Current: 350 mA
• Signal Delay (AC Off): 45 ± 15 ms typical
• Signal Delay (DC Off): 50 ms typical
• Wiring Arm: 1771-WH
• Protection: Protected output circuitry
• Coating: Conformal coating
• Mounting: Rack mountable
• Operating Temperature: 0–60 °C (32–140 °F)
• Weight: 1.43 lbs (649 g)

Features & Benefits

• Protected Output Circuitry: Built-in protection safeguards against overload and short-circuit conditions
• Conformal Coating: Environmental protection for reliable operation in harsh industrial conditions
• Compact 4-Channel Design: Efficient I/O density for applications requiring fewer AC outputs
• Status Indicators: Visual LED indicators for output state monitoring and diagnostics
• Standard Wiring Arm: Uses 1771-WH for consistent installation with other 1771 modules
• Wide Voltage Range: 92–138V AC accommodates typical industrial power variations

Applications

• AC motor starter control
• Solenoid valve switching
• Indicator light and alarm control
• Heater element control
• Legacy PLC-5 system maintenance and repair

Installation Guide

1. Chassis Preparation: Install the 1771-OP into a compatible 1771-series I/O chassis. Verify backplane power capacity.
2. Wiring Arm Attachment: Connect the 1771-WH wiring arm to the module for field terminal access.
3. Load Connection: Wire AC loads (92–138V AC, 47–63 Hz) to the output terminals. Do not exceed 2A per point or 6A total.
4. Protection Verification: The module features protected output circuitry, but verify external circuit protection is adequate for your application.
5. Environmental Considerations: Install in properly ventilated enclosures. Maintain 0–60 °C operating temperature range.

FAQ

Q: What does "protected output" mean on the 1771-OP?
A: The module includes internal protection circuitry to guard against overload and short-circuit conditions, enhancing reliability and reducing external protection component requirements.

Q: Can I use the 1771-OP for DC output applications?
A: No. The 1771-OP is designed exclusively for AC loads (92–138V AC). For DC output, use modules such as 1771-OBD or 1771-ODD.

Q: How many outputs does the 1771-OP provide?
A: The 1771-OP provides 4 AC output channels, compared to 16 channels on the 1771-OD16.

Q: Is the 1771-OP still available new?
A: The 1771-OP is a discontinued legacy product. It is available through surplus channels for existing system maintenance.

Selection Tips

• Choose 1771-OP for applications needing 4 or fewer AC outputs with built-in protection
• For higher channel density, consider 1771-OD16 (16 channels)
• Verify load current does not exceed 2A per point or 6A module total
• Ensure AC load voltage stays within 92–138V AC range
• For new designs, evaluate migration to ControlLogix 1756-OA8I or CompactLogix output modules