Allen-Bradley 5094-OB16 FLEX 5000 16-Point DC Output Module

Diagnostic 24 V DC sourcing outputs for harsh sites

The Allen-Bradley 5094-OB16 is a sixteen-point 24 V DC sourcing output module with comprehensive protection. Each channel carries 0.5 A, the module is designed for 18 to 32 V DC, and diagnostics include open-load detection in the off state, short-circuit, overload and over-temperature detection in the on state, and reverse-voltage protection.

Together with scheduled outputs and CIP Sync, this makes it suitable for time-critical valve and solenoid control in demanding environments, from -40 to +70 C.

Technical specifications

Diagnostics in service

Open-load detection is active when the output is off and short-circuit/overload detection when it is on, so the controller reports a broken solenoid wire before the valve is called to operate. Where leakage current is a problem with sensitive loads, the manufacturer recommends a 5.6 kOhm, 0.5 W loading resistor for a 24 V DC transistor output. Fault-state behaviour is set per point, so each valve can fail to hold, open or close.

Selection notes

Select this module for solenoids, lamps and relay coils up to 0.5 A each. For 1 A or higher loads, an interposing relay is needed. The mounting base, RTB and a 24 V DC SA supply (up to 8.1 A per module) must be ordered with it. Confirm every value against the manufacturer publication and your valve data. The module reports its own status, SA power status and sixteen channel states with indicators on the front, which helps when a solenoid circuit is being traced at night during a shutdown.

Fault behaviour is configurable per point: hold last state, on, or off (the default), with a fault duration of 1, 2, 5, 10 s or forever. Combined with open-load, short-circuit, overload and overtemperature diagnostics, this lets the program decide how each valve or relay behaves if the network is lost.

Typical application context

The 5094-OB16 is used in FLEX 5000 I/O systems wherever a Logix controller has to switch DC loads in the field: solenoid valves on process skids and machines, pilot relays for motor starters, signal lamps, and similar loads within the stated current per channel. In remote I/O cabinets on processing lines, water and wastewater stations or packaging machinery, the combination of sixteen points in one module and per-point diagnostics helps reduce wiring effort and fault-finding time.

Scheduled outputs and CIP Sync are relevant where an output must switch at a defined time relative to other events, for example when a reject valve has to act on a product detected further upstream. In such cases the timing is handled by the module rather than depending on the program scan.

Planning loads and power

Check each load against the per-channel rating and the surge capability, and remember that the SA supply has to carry the sum of all outputs that can be on at the same time. Inductive loads such as solenoids and relay coils should be reviewed against the manufacturer guidance for this module. Where several modules share an SA supply, size the supply and its protection for the combined load, and plan the power distribution in the FLEX 5000 bank accordingly.

Define the fault-state behaviour for every point during engineering, not only at commissioning. Decide which outputs should switch off, which should hold, and which should switch on if communication is lost, and for how long, so that the plant moves to a safe condition that matches the process design.

Installation and commissioning considerations

Order and install the mounting base and removable terminal base as separate items, and use the mechanical keying to protect each slot against the wrong module type. Set the electronic keying in the programming software according to site practice. Keep the field wiring of DC outputs separate from analog signals and power cables, and label each channel clearly to support later fault-finding.

During commissioning, force each output individually and confirm that the correct load responds. Test the open-load diagnostic by disconnecting a load while the output is off, and confirm that the fault is reported to the controller and the operator interface as intended. Verify the configured fault-state behaviour by interrupting communication under controlled conditions.

How to specify your request

State the catalog number 5094-OB16 or 5094-OB16XT, as required, together with the quantity. Mention whether mounting bases and terminal bases should be included in the same request, and name the controller and adapter in use so that the configuration can be checked within the FLEX 5000 system.

If the module replaces an installed unit, quote the catalog number printed on the existing module. A short description of the loads per channel, such as solenoid valves, pilot relays or lamps, also helps to confirm that this output module is the right match for the application before the offer is prepared.

Documents and quotation

The linked Rockwell Automation technical data (about 10.8 MB, hosted by Rockwell Automation) covers all FLEX 5000 I/O modules and adapters. Related modules appear in PLC & I/O Cards. To request a quotation send the catalog number and quantity to Seven Star LLC, an independent supplier in Muscat.