Allen-Bradley 1756-OB8I Digital Output Module

Series#: AllenBradley

Product Details

1756-OB8I Allen-Bradley ControlLogix Isolated DC Output Module – high-performance for industrial automation.
8-point isolated sourcing output module, 10-31.2V DC rated, with 2A per point at 30V DC maximum.
Individual channel-to-backplane isolation (50V continuous) for enhanced system reliability and noise immunity.
Supports electronic fusing and diagnostics per point, reducing downtime in critical processes.
Hot-swappable in ControlLogix chassis (1756-A4/A7/A10/A13/A17) for seamless maintenance.
Backward compatible with all ControlLogix 1756 series controllers and communication modules.
100% Brand New & Original, securely packed and ready for reliable global shipping.

Specification

The 1756-OB8I is a robust 8-point isolated DC output module from the Allen-Bradley ControlLogix family, engineered for demanding industrial environments where signal integrity and protection are paramount. This module provides 8 individually isolated sourcing outputs, each capable of handling up to 2A at 30V DC, with a voltage range of 10-31.2V DC. Its per-channel isolation (50V continuous from backplane) ensures that ground loops and electrical noise do not compromise system performance, making it ideal for applications in manufacturing, oil and gas, and water treatment. The 1756-OB8I supports advanced diagnostics, including open wire detection and electronic short-circuit protection, which are configurable via the ControlLogix backplane. It is fully compatible with standard ControlLogix chassis and operates in temperatures from 0 to 60°C (32 to 140°F). For precise control, the module offers fast response times (0.5 ms typical off-to-on, 1.0 ms on-to-off) and is rated for 250V AC/125V DC isolation from system to field. This module is designed for easy installation with a removable terminal block (RTB) and supports up to 10 mA backplane current draw at 5.1V DC. The 1756-OB8I is a reliable choice for applications requiring high channel density with galvanic isolation, ensuring long-term stability and minimal maintenance.

Parameter	Specification
Module Type	Isolated DC Output Module
Number of Outputs	8 (sourcing, isolated per channel)
Output Voltage Range	10-31.2V DC (rated 24V DC nominal)
Output Current per Point	2A at 30V DC maximum (continuous)
Total Output Current per Module	8A (sum of all points, limited by thermal conditions)
Isolation Voltage	50V continuous (channel-to-backplane); 250V AC/125V DC (system-to-field)
Output Response Time	Off-to-On: 0.5 ms typical; On-to-Off: 1.0 ms typical
Backplane Current Draw	10 mA at 5.1V DC; 0 mA at 24V DC
Power Dissipation	2.5 W typical (at 24V DC, 2A per point)
Thermal Dissipation	8.5 BTU/hr typical
Operating Temperature	0 to 60°C (32 to 140°F)
Storage Temperature	-40 to 85°C (-40 to 185°F)
Relative Humidity	5% to 95% non-condensing
Vibration Resistance	2 g Standard Models 10-500 Hz (operating)
Shock Resistance	30 g (operating); 50 g (non-operating)
Terminal Type	Removable Terminal Block (RTB), 36-position, screw clamp
Wire Size	0.33 to 2.5 mm² (22-14 AWG) stranded or solid
Module Keying	Electronic keying (software configurable)
Diagnostics	Open wire detection, short-circuit protection, electronic fusing per point
Indicators	Green/Red LED per channel (status/fault); Module status LED (OK/FLT)
Compatible Chassis	1756-A4, A7, A10, A13, A17 (ControlLogix standard)
Communication	Via ControlLogix backplane (ControlNet, EtherNet/IP, DeviceNet, etc.)
Approvals	UL, cUL, CE, ATEX (Zone 2), IECEx, Marine (ABS, DNV, Lloyds)
Weight	Approx. 0.35 kg (0.77 lb)
Dimensions (H x W x D)	144 x 35.5 x 127 mm (5.67 x 1.40 x 5.00 in)
Warranty	Standard 2-year manufacturer warranty