1794-OB32P — FLEX I/O 32-Point 24V DC Protected Transistor Output Module

The 1794-OB32P puts 32 sourcing 24V DC transistor outputs into a single FLEX I/O module slot. The "P" in the part number stands for protected — each output has individual electronic short-circuit and overload protection, meaning a fault on one point doesn't pull down the entire output group. That per-point protection is the key differentiator from standard 32-point output modules and makes a practical difference when you're switching 32 independent loads across a machine.

FLEX I/O is a distributed I/O platform designed for remote mounting near field devices, connected back to the controller via an adapter module over EtherNet/IP, ControlNet, DeviceNet, or other networks. The 1794-OB32P is physically compact — 32 outputs in the standard FLEX I/O housing width — which suits the space-constrained enclosures typical in distributed architecture installations.

Specifications

Parameter	Value
Part Number	1794-OB32P
Platform	FLEX I/O (1794)
Output Points	32
Output Type	Sourcing (PNP) transistor, protected
Output Voltage	24V DC (10–30V)
Output Current per Point	0.5 A continuous
Short-Circuit Protection	Electronic, per point (individual)
Overload Protection	Yes, per point — auto-resets after fault clears
Output Groups	2 × 16 points
Fault Reporting	Per-point fault status bits in I/O image
Backplane Current (5V)	300 mA
Field Power	24V DC (user-supplied via terminal base)
Operating Temperature	0°C to 55°C
Standards	IEC 61131-2, UL 508, CE

High-Density Output Applications

Thirty-two outputs in one slot finds its home in applications where output point count is high and space is limited:

Valve manifold control — pneumatic manifolds with 16–32 solenoids are common in assembly and test machines. One 1794-OB32P handles an entire manifold block from a single module slot.
Indicator panel arrays — status indication panels with large numbers of LEDs or pilot lights. At 30–50 mA per LED, all 32 points can be on simultaneously with total current well within the module's supply budget.
Distributed tool changers and end-effectors — robotic end-of-arm tooling with multiple gripper actuators, vacuum generators, and sensor enable outputs benefits from the protected outputs — a vacuum line blockage causing overcurrent on one solenoid point doesn't kill the rest of the tooling.

FAQ

Q: Does per-point protection replace the need for external fusing?

No. Per-point protection safeguards the module's output transistors. External fusing on the field power supply to the terminal base is still required for branch circuit protection and NEC/IEC code compliance.

Q: When an output faults, does it require a controller command to reset?

The overload protection auto-resets when the overcurrent condition clears. Whether the output comes back on automatically depends on the controller program's output logic — if the output tag is still set to 1 in the program when the fault clears, the output will re-energize automatically.

Q: What FLEX I/O adapter modules are compatible?

The 1794-OB32P works with all standard 1794 FLEX I/O adapter modules — 1794-AENT (EtherNet/IP), 1794-ADN (DeviceNet), 1794-ACN (ControlNet), and others. The module is adapter-agnostic; the adapter determines network protocol.

Q: Can the fault status bits trigger an alarm in the HMI?

Yes. The fault bits are available in the controller's I/O data like any other tag. Mapping them to an HMI alarm screen with the point number and a descriptive label takes a few minutes in the HMI configuration and gives the operator exact fault location without a panel walkdown.

1794-OB32P New Factory Sealed A 32 Point Digital Output Module 1794OB32P