Allen-Bradley 1769-OB32T CompactLogix Digital Output Module
Functional Overview
The Allen-Bradley 1769-OB32T functions as a high-density interface that transmits control signals from the PLC processor to field actuators. Specifically, the module provides 32 sourcing outputs divided into two isolated groups of 16 channels, operating across a standard 24 VDC industrial logic range. Because sourcing (source-type) outputs supply current from the positive DC rail directly to the connected load, they ensure compatibility with standard sinking field devices. Furthermore, the electronic circuitry switches rapidly, supporting high-repetition machine sequencing. Therefore, this hardware serves as a dependable execution layer for packaging lines, material handling systems, and assembly cells.
High-Density Channel Architecture
Space efficiency defines the hardware value of the 1769-OB32T. By consolidating 32 outputs into a single compact module width, it reduces the number of expansion racks and cable routing paths required in the control enclosure. Additionally, the internal circuit utilizes optocouplers to provide robust electrical isolation between the sensitive backplane logic and external field wiring loops. Consequently, this barrier blocks voltage spikes and high-frequency noise from propagating back to the CompactLogix CPU, preserving overall system stability.
Onboard Diagnostic Capabilities
The 1769-OB32T streamlines troubleshooting through integrated physical indicators and software diagnostics. The front faceplate incorporates a high-visibility LED matrix display mapping the status of all 32 channels. During normal operation, these LEDs immediately illuminate to verify active output gating. Meanwhile, the module communicates fault words to the controller data files if an external power drop occurs or communication with the bus master degrades. In other words, the hardware allows maintenance teams to quickly distinguish between field wiring anomalies and internal system events.
Technical Specifications
The 1769-OB32T delivers exceptional power-to-size performance parameters within a standard 1769 form factor.
| Feature | Specification |
| Output Type | Solid-state Sourcing (Source) |
| Number of Outputs | 32 Channels (2 Groups of 16) |
| Operating Voltage Range | 20.4 to 26.4 V DC |
| Max. Output Current per Point | 0.5 A |
| Max. Output Current per Module | 4.0 A (2.0 A per group) |
| Surge Current Capability | 1.0 A for 10 ms (repeatable every 2 sec) |
| Power Supply Distance Rating | 8 Modules Max (from power supply unit) |
| Removable Terminal Block | 1769-RT32 (Included) |
Installation and Power Distribution Guidelines
To begin assembly, ensure the CompactLogix system power is completely disconnected. First, slide the Allen-Bradley 1769-OB32T along the integrated tongue-and-groove slots of the adjacent module until it locks into the bus backplane. Next, slide the module bus levers to the left to firmly engage the internal communication links.
Furthermore, wire your external 24 VDC power supply sources directly to the 1769-RT32 removable terminal block, supplying separate power inputs to terminal groups V1(+) / COM1(-) and V2(+) / COM2(-). Meanwhile, ensure the total current draw for each group does not exceed the 2.0 A threshold under full load conditions. Finally, establish your module configuration within the Studio 5000 Logix Designer I/O tree, verifying that electronic keying properties match your field hardware version.
Packaging List
-
1 x Allen-Bradley 1769-OB32T 32-Point Output Module
-
1 x 1769-RT32 32-Point Removable Terminal Block Assembly
-
1 x Bus Extension Protective Cap
-
Shipping Carrier Availability: DHL, FedEx, UPS, TNT
FAQ
Q: Does the 1769-OB32T support short-circuit protection on its outputs?
No. Specifically, the 1769-OB32T does not include internal electronic short-circuit protection. You must install external fuses or circuit breakers to safeguard individual output channels against dead shorts.
Q: Can I mix different voltages between the two output groups?
Yes. Because Group 1 and Group 2 are electrically isolated from each other, you can supply independent 24 VDC power sources to each section if required by your field layout.
Q: What is the purpose of the "T" suffix in the model number?
The "T" designates that this module utilizes sourcing transistor outputs with high-density spacing, distinguishing it from relay modules or sinking variations.
Q: What is the maximum distance this module can be placed from the system power supply?
The module features a power supply distance rating of 8. This means it cannot sit more than 8 module slots away from an active 1769 power supply unit
