Implementing 3-Switch XOR Ladder Logic with Internal Bit
Implement a 3-SPST switch XOR light circuit in LogixPro or RSLogix 500 using an internal relay bit. Includes truth tables, boolean equations, and verified.
The Allen-Bradley 1756-L85EPXT is a ControlLogix 5580 Process XT Controller designed for process automation and extended-temperature ControlLogix applications.
The controller provides 40 MB of user memory and an embedded 1 Gb EtherNet/IP port for controller communication, distributed I/O, and integrated motion applications. It supports up to 300 EtherNet/IP nodes.
The Process controller architecture is optimized for process applications. The XT configuration extends environmental capability for installations using compatible ControlLogix-XT or ControlLogix-ZXT chassis.
The controller is conformally coated for operation in corrosive industrial environments. A 2 GB Secure Digital card is supplied preinstalled for nonvolatile program and tag-data storage.
ControlLogix 5580 Process XT controller
40 MB user memory
Embedded 1 Gb EtherNet/IP interface
Up to 300 EtherNet/IP nodes
Integrated Motion over EtherNet/IP capability
Optimized for process control applications
Extended-temperature XT configuration
Conformal-coated construction
Corrosive-atmosphere capability
USB port for temporary local programming
4-character alphanumeric status display
SD card slot for nonvolatile memory
2 GB 1784-SD2 card supplied preinstalled
Digitally signed and encrypted controller firmware
Supports installation in compatible ControlLogix chassis
Process automation systems
Distributed process control
Large EtherNet/IP architectures
Integrated controller and motion applications
Harsh and corrosive industrial environments
Extended-temperature ControlLogix installations
High-capacity ControlLogix controller replacement
| Parameter | Specification |
|---|---|
| Manufacturer | Allen-Bradley |
| Catalog Number | 1756-L85EPXT |
| Product Type | Process XT Controller |
| Product Family | ControlLogix 5580 |
| Bulletin | 1756 |
| User Memory | 40 MB |
| EtherNet/IP Nodes | Up to 300 |
| Lifecycle Status | Active |
| UPC | 195272618777 |
| Secure Digital Card | 2 GB 1784-SD2, preinstalled |
| Conformal Coating | Yes |
| Enclosure Type | Open-style |
| Weight | Approx. 394 g (0.868 lb) |
| Parameter | Specification |
|---|---|
| Embedded Ethernet | 1 Gb Ethernet |
| Industrial Network | EtherNet/IP |
| Ethernet Connector | RJ45 |
| USB | Available for temporary local programming |
| Status Display | 4-character alphanumeric display |
| Parameter | Specification |
|---|---|
| Backplane Current | 1200 mA at 5.1 VDC |
| Backplane Current | 5.0 mA at 1.2 VDC |
| Isolation Voltage | 50 V continuous |
| Isolation Type | Basic insulation |
| Isolation Test | 1000 VAC for 60 seconds |
| Parameter | Specification |
|---|---|
| Operating Temperature, Standard Series C Chassis | -25 to +60 degC |
| Operating Temperature, Standard Series B Chassis | -25 to +50 degC |
| Operating Temperature, XT Series C Chassis | -25 to +70 degC |
| Operating Temperature, ZXT Chassis | -25 to +70 degC |
| Maximum Surrounding Air, XT / ZXT | 70 degC |
| Temperature Code | T4 |
| Pollution Degree | 2 |
| Parameter | Specification |
|---|---|
| Width | 34.55 mm (1.360 in.) |
| Height | 145.2 mm (5.717 in.) |
| Depth | 139.6 mm (5.50 in.) |
| Weight | Approx. 394 g (0.868 lb) |
| Interface | Function |
|---|---|
| EtherNet/IP Port | Controller communication, I/O, and integrated motion |
| USB Port | Temporary local programming |
| SD Card Slot | Nonvolatile program and tag-data storage |
| ControlLogix Backplane | Chassis communication and controller power |
| Mode Switch | Remote, Run, and Program operating modes |
Verify the complete 1756-L85EPXT catalog number before replacement.
Confirm the selected chassis and power supply support the Process XT controller.
Use an XT Series C or ZXT chassis when the +70 degC operating range is required.
Back up the existing Studio 5000 project before replacing an operating controller.
Record EtherNet/IP addresses and controller communication settings before removal.
Keep unused port protection plugs installed where corrosive-atmosphere performance must be maintained.
Verify the preinstalled SD card and project configuration before startup.
Check the 4-character display and status indicators after chassis power is applied.
Match the Process XT configuration rather than replacing it solely by memory size.
Preserve project revision, network configuration, firmware compatibility, and process-controller settings.
The 1756-L85EPXT is the direct replacement identified by Rockwell Automation for the 1756-L85EP.
Global Express Shipping
Returns & Warranty

The Allen-Bradley 1756-L85EPXT is a ControlLogix 5580 Process XT Controller designed for process automation and extended-temperature ControlLogix applications.
The controller provides 40 MB of user memory and an embedded 1 Gb EtherNet/IP port for controller communication, distributed I/O, and integrated motion applications. It supports up to 300 EtherNet/IP nodes.
The Process controller architecture is optimized for process applications. The XT configuration extends environmental capability for installations using compatible ControlLogix-XT or ControlLogix-ZXT chassis.
The controller is conformally coated for operation in corrosive industrial environments. A 2 GB Secure Digital card is supplied preinstalled for nonvolatile program and tag-data storage.
ControlLogix 5580 Process XT controller
40 MB user memory
Embedded 1 Gb EtherNet/IP interface
Up to 300 EtherNet/IP nodes
Integrated Motion over EtherNet/IP capability
Optimized for process control applications
Extended-temperature XT configuration
Conformal-coated construction
Corrosive-atmosphere capability
USB port for temporary local programming
4-character alphanumeric status display
SD card slot for nonvolatile memory
2 GB 1784-SD2 card supplied preinstalled
Digitally signed and encrypted controller firmware
Supports installation in compatible ControlLogix chassis
Process automation systems
Distributed process control
Large EtherNet/IP architectures
Integrated controller and motion applications
Harsh and corrosive industrial environments
Extended-temperature ControlLogix installations
High-capacity ControlLogix controller replacement
| Parameter | Specification |
|---|---|
| Manufacturer | Allen-Bradley |
| Catalog Number | 1756-L85EPXT |
| Product Type | Process XT Controller |
| Product Family | ControlLogix 5580 |
| Bulletin | 1756 |
| User Memory | 40 MB |
| EtherNet/IP Nodes | Up to 300 |
| Lifecycle Status | Active |
| UPC | 195272618777 |
| Secure Digital Card | 2 GB 1784-SD2, preinstalled |
| Conformal Coating | Yes |
| Enclosure Type | Open-style |
| Weight | Approx. 394 g (0.868 lb) |
| Parameter | Specification |
|---|---|
| Embedded Ethernet | 1 Gb Ethernet |
| Industrial Network | EtherNet/IP |
| Ethernet Connector | RJ45 |
| USB | Available for temporary local programming |
| Status Display | 4-character alphanumeric display |
| Parameter | Specification |
|---|---|
| Backplane Current | 1200 mA at 5.1 VDC |
| Backplane Current | 5.0 mA at 1.2 VDC |
| Isolation Voltage | 50 V continuous |
| Isolation Type | Basic insulation |
| Isolation Test | 1000 VAC for 60 seconds |
| Parameter | Specification |
|---|---|
| Operating Temperature, Standard Series C Chassis | -25 to +60 degC |
| Operating Temperature, Standard Series B Chassis | -25 to +50 degC |
| Operating Temperature, XT Series C Chassis | -25 to +70 degC |
| Operating Temperature, ZXT Chassis | -25 to +70 degC |
| Maximum Surrounding Air, XT / ZXT | 70 degC |
| Temperature Code | T4 |
| Pollution Degree | 2 |
| Parameter | Specification |
|---|---|
| Width | 34.55 mm (1.360 in.) |
| Height | 145.2 mm (5.717 in.) |
| Depth | 139.6 mm (5.50 in.) |
| Weight | Approx. 394 g (0.868 lb) |
| Interface | Function |
|---|---|
| EtherNet/IP Port | Controller communication, I/O, and integrated motion |
| USB Port | Temporary local programming |
| SD Card Slot | Nonvolatile program and tag-data storage |
| ControlLogix Backplane | Chassis communication and controller power |
| Mode Switch | Remote, Run, and Program operating modes |
Verify the complete 1756-L85EPXT catalog number before replacement.
Confirm the selected chassis and power supply support the Process XT controller.
Use an XT Series C or ZXT chassis when the +70 degC operating range is required.
Back up the existing Studio 5000 project before replacing an operating controller.
Record EtherNet/IP addresses and controller communication settings before removal.
Keep unused port protection plugs installed where corrosive-atmosphere performance must be maintained.
Verify the preinstalled SD card and project configuration before startup.
Check the 4-character display and status indicators after chassis power is applied.
Match the Process XT configuration rather than replacing it solely by memory size.
Preserve project revision, network configuration, firmware compatibility, and process-controller settings.
The 1756-L85EPXT is the direct replacement identified by Rockwell Automation for the 1756-L85EP.
Global Express Shipping
Returns & Warranty
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For full eligibility, restocking fees, and international return details, please view our official Refund & Return Policy .
| Country of origin |
United States
|