Overview
The Allen-Bradley 1756-OF6VI is a ControlLogix isolated analog output module designed to deliver precise voltage signals in industrial automation environments. This module features six individually isolated voltage output channels, each capable of generating ±10 VDC signals. The isolation between channels allows continued operation even if a single channel fails, enhancing system reliability and eliminating the need for external isolation barriers on field wiring.
Key Features
- Six (6) individually isolated voltage output channels
- Output range: ±10.5 VDC with 14-bit resolution across 21V (1.3 mV per bit)
- 250V isolation voltage between channels and to backplane, tested at 1350V AC for 2 seconds
- Overvoltage protection at 24V DC plus electronic short-circuit protection
- Compact 20-pin connector; occupies single ControlLogix chassis slot
- Settling time less than 2 milliseconds to 95% of final value with resistive loads
Technical Specifications
- Output Channels: 6 individually isolated
- Output Signal: Voltage; Range ±10.5 VDC
- Resolution: 14 bits across 21V (1.3 mV)
- Isolation Rating: 250V continuous, basic insulation
- Output Accuracy: Better than 0.1% of range; recalibration every 6 months
- Module Error Margin: 0.5% overall
- Scan Time: 10 ms (integer mode), 25 ms (floating-point mode)
- Backplane Current Draw: 175 mA @ 24 VDC; 250 mA @ 5.1 VDC
- Backplane Power: Maximum 5.5W; 4.85W dissipation
- Output Load Drive: Greater than 1000 Ω loads, 10 mA capability
- Output Impedance: 1 Ohm
- Operating Temperature: 0–60°C @ 5–95% RH (non-condensing)
- Certifications: CSA, CE, KC, Marine, NRTL, RCM, UL
- Weight: 0.895 lbs (0.41 kg)
- Connector Type: 20-pin; compatible RTBs: 1756-TBNH, 1756-TBSH
- Environmental Shock: 30G operational; Vibration 2G @ 10–500 Hz
Typical Applications
The 1756-OF6VI is commonly deployed in:
- Process control loops requiring isolated analog outputs (pressure, temperature, flow)
- Motor and drive control systems needing precise voltage command signals
- Distributed I/O architectures in modular automation cabinets
- Systems requiring individual channel redundancy and failure tolerance
- Field device configuration via Add-on Profiles in RSLogix 5000 / Studio 5000
Compatibility & Replacements
The 1756-OF6VI /A is a member of the ControlLogix 1756 analog I/O family and slots into any available ControlLogix chassis slot (1756-A2, 1756-A4, 1756-A7, 1756-A10, etc.). It is supported by Rockwell Automation Studio 5000 (Version 31.00+) and earlier RSLogix 5000 environments. Related modules include the 1756-OF6CI (isolated current output), 1756-OF4 (4-point output), and the newer 1756-OF8I/1756-OF8IK (8-point combined I/O). The module requires firmware updates via Rockwell Automation’s literature portal. Compatible terminal block housings are model 1756-TBNH (standard) and 1756-TBSH (slim profile).
