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.
Designed for seamless integration within modular industrial control environments, the Beckhoff CX1500-M200 fieldbus master connection establishes high-speed Lightbus communications directly from a compatible CX-series CPU. By utilizing fiber optic physical layers, this interface module guarantees complete electrical isolation and exceptional noise immunity across distributed field systems. The integration with the host controller is achieved through a high-bandwidth 2 kbytes DPRAM interface over an ISA plug-and-play architecture, ensuring rapid cyclic data exchanges. Perfect for synchronized motion and distributed I/O systems, the device supports both free-running and synchronized process data communication modes depending on the application requirements.
| Parameter | Specification Value |
|---|---|
| Manufacturer | Beckhoff |
| Model / Article Number | CX1500-M200 |
| Fieldbus System | Lightbus |
| Data Transfer Rate | 2.5 Mbaud |
| Process Data Cycle Time | 32 bits in 25 microseconds |
| Bus Interface | 2 x fiber optic ports |
| Maximum Nodes | 254 nodes (max. 65,280 I/O points) |
| CPU Interface | ISA plug and play, 2 kbytes DPRAM |
| Max. Power Loss | 2 W |
| Operating Temperature | 0 to +55 degC |
| Storage Temperature | -25 to +85 degC |
| Relative Humidity | 95%, non-condensing |
| Protection Rating | IP20 |
| Driver Support | Compatible only with TwinCAT 2 |
| Vibration/Shock Resistance | Conforms to EN 60068-2-6 / EN 60068-2-27 |
| EMC Immunity/Emission | Conforms to EN 61000-6-2 / EN 61000-6-4 |
| Approvals | CE, UL |
| Dimensions (W x H x D) | 38 mm x 100 mm x 91 mm |
| Net Weight | 190 g |
| Shipping Weight (Calculated) | 2.0 kg |
| Port / Interface Type | Function / Assignment |
|---|---|
| Optical Port 1 (Tx) | Lightbus optical transmitter connection to the ring network. |
| Optical Port 2 (Rx) | Lightbus optical receiver connection completing the ring loop. |
| Backplane Interface | Integrated PC104/ISA Bus for physical connection and power distribution from the CX CPU. |
The CX1500-M200 is designed exclusively for CX-series hardware configurations operating under TwinCAT 2 runtimes. It cannot be mapped or configured under TwinCAT 3 due to the hardware-level dependencies of the legacy ISA DPRAM address space. Ensure your system CPU supports PC104 expansion channels before engineering replacements.
When laying optical fiber cables for the Lightbus loop, strictly adhere to the manufacturer's specified minimum bending radius. Kinking or over-bending the optical fibers causes critical light signal attenuation, leading to intermittent cyclic redundancy check (CRC) errors or complete bus synchronization failures.
Always power down the control stack before cleaning or inserting optical fiber connectors. Dust ingress within the active physical transceivers can permanently degrade light output. Prior to initial startup, verify the mechanical alignment of the CPU extension connector to avoid bent pins on the backplane.
Isolate and lock out all power sources feeding the host controller and connected field devices before initiating module insertion or removal. Failing to perform total system de-energization may damage the sensitive DPRAM physical layer of the host CPU and invalidate your warranty.
Global Express Shipping
Returns & Warranty

Designed for seamless integration within modular industrial control environments, the Beckhoff CX1500-M200 fieldbus master connection establishes high-speed Lightbus communications directly from a compatible CX-series CPU. By utilizing fiber optic physical layers, this interface module guarantees complete electrical isolation and exceptional noise immunity across distributed field systems. The integration with the host controller is achieved through a high-bandwidth 2 kbytes DPRAM interface over an ISA plug-and-play architecture, ensuring rapid cyclic data exchanges. Perfect for synchronized motion and distributed I/O systems, the device supports both free-running and synchronized process data communication modes depending on the application requirements.
| Parameter | Specification Value |
|---|---|
| Manufacturer | Beckhoff |
| Model / Article Number | CX1500-M200 |
| Fieldbus System | Lightbus |
| Data Transfer Rate | 2.5 Mbaud |
| Process Data Cycle Time | 32 bits in 25 microseconds |
| Bus Interface | 2 x fiber optic ports |
| Maximum Nodes | 254 nodes (max. 65,280 I/O points) |
| CPU Interface | ISA plug and play, 2 kbytes DPRAM |
| Max. Power Loss | 2 W |
| Operating Temperature | 0 to +55 degC |
| Storage Temperature | -25 to +85 degC |
| Relative Humidity | 95%, non-condensing |
| Protection Rating | IP20 |
| Driver Support | Compatible only with TwinCAT 2 |
| Vibration/Shock Resistance | Conforms to EN 60068-2-6 / EN 60068-2-27 |
| EMC Immunity/Emission | Conforms to EN 61000-6-2 / EN 61000-6-4 |
| Approvals | CE, UL |
| Dimensions (W x H x D) | 38 mm x 100 mm x 91 mm |
| Net Weight | 190 g |
| Shipping Weight (Calculated) | 2.0 kg |
| Port / Interface Type | Function / Assignment |
|---|---|
| Optical Port 1 (Tx) | Lightbus optical transmitter connection to the ring network. |
| Optical Port 2 (Rx) | Lightbus optical receiver connection completing the ring loop. |
| Backplane Interface | Integrated PC104/ISA Bus for physical connection and power distribution from the CX CPU. |
The CX1500-M200 is designed exclusively for CX-series hardware configurations operating under TwinCAT 2 runtimes. It cannot be mapped or configured under TwinCAT 3 due to the hardware-level dependencies of the legacy ISA DPRAM address space. Ensure your system CPU supports PC104 expansion channels before engineering replacements.
When laying optical fiber cables for the Lightbus loop, strictly adhere to the manufacturer's specified minimum bending radius. Kinking or over-bending the optical fibers causes critical light signal attenuation, leading to intermittent cyclic redundancy check (CRC) errors or complete bus synchronization failures.
Always power down the control stack before cleaning or inserting optical fiber connectors. Dust ingress within the active physical transceivers can permanently degrade light output. Prior to initial startup, verify the mechanical alignment of the CPU extension connector to avoid bent pins on the backplane.
Isolate and lock out all power sources feeding the host controller and connected field devices before initiating module insertion or removal. Failing to perform total system de-energization may damage the sensitive DPRAM physical layer of the host CPU and invalidate your warranty.
Global Express Shipping
Returns & Warranty
Orders are processed and delivered Monday-Friday (excluding public holidays).
For full eligibility, restocking fees, and international return details, please view our official Refund & Return Policy .
| Country of origin |
Germany
|