Configured for high-density relay output execution in Allen-Bradley 1771 Universal I/O Chassis platforms, the Allen-Bradley 1771-OWNA (1771-OWNA Digital Contact Output Module) provides direct physical/electrical execution.
Suffix Breakdown & Model Matrix
1771: Universal I/O platform hardware family for PLC-5 automation systems.
A: Factory conformal coating option for environmental and chemical resistance.
Hardware Specifications
Parameter
Specification
Model
1771-OWNA
Brand
Allen-Bradley
Origin
USA
Weight
2.00 lbs (0.91 kg)
Dimensions
Standard 1771 single-slot chassis module
Operating Temp
0 to 60 deg C (32 to 140 deg F)
Power Consumption
12.5 W maximum (all relays active)
Backplane Current
1.8 A nominal, 2.5 A maximum at 5 VDC
Output Channels
32 (4 isolated groups of 8)
Contact Type
32 Normally Open (N.O.) electromechanical relays
AC Operating Voltage
24 to 138 VAC RMS
DC Operating Voltage
24 to 125 VDC
Max Continuous Current
12 A total per module (at 45 deg C)
Wiring Arm
1771-WH
High-Density I/O Isolation and Deterministic Network Response
The 1771-OWNA module leverages high-density I/O scaling to manage up to 32 discrete load circuits while maintaining electrical isolation between backplane logic and field-side contacts. Designed to operate alongside EtherNet/IP deterministic networks and remote I/O scanners, the internal switching logic isolates electrical transients and surge back-EMF, ensuring stable backplane bus communication velocity across adjacent PLC-5 submodules.
Frequently Asked Questions
Q: What is the backplane current draw requirement for the 1771-OWNA relay module?
A: The 1771-OWNA draws 1.8 A nominal and up to 2.5 A maximum from the chassis 5 VDC backplane bus when all 32 output relays are fully energized.
Q: How does operating temperature affect the maximum continuous output current of the module?
A: Up to 45 deg C, the module supports a maximum total current of 12 A. Above 45 deg C, total module current derates linearly at 0.4 A per deg C up to the maximum operating threshold of 60 deg C.
Field Installation Guidelines
Confirm that backplane supply power and field wiring power are fully disconnected before inserting the module into or removing it from the 1771 chassis slot.
Verify that the 1771-WH field wiring arm is correctly keyed and securely seated to ensure low-resistance pin contact across all 32 output channels.
Observe external fusing and load requirements to ensure total current per group of 8 channels does not exceed 4 A at ambient temperatures up to 45 deg C.
Keep field signal wiring separated from high-voltage AC mains and high-frequency noise sources to avoid unwanted inductance across contact leads.
