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 BECKHOFF KS6021 is a high-performance Bus Terminal with a pluggable wiring level, designed to enable direct connection of devices with RS422 or RS485 interfaces to the K-bus system. It provides an electrically isolated, interference-immune interface for bidirectional data transfer over long distances, making it highly suitable for integrating serial communication devices into standard Beckhoff I/O networks.
Operating in full or half-duplex mode, the BECKHOFF KS6021 transmits and receives differential signals using a dedicated TxD and RxD channel architecture. The serial interface operates independently of the underlying bus system, allowing the controller to transmit data collision-free and receive data with an integrated buffer system. This model features a pluggable wiring design (indicated by the KS prefix), which simplifies terminal installation, replacement, and wiring verification without disconnecting individual field conductors.
| Manufacturer | BECKHOFF |
| Model | KS6021 |
| Product Type | Bus Terminal with pluggable wiring level |
| Communication Interface | RS422/RS485 |
| Data Channels | TxD and RxD, full or half-duplex |
| Data Transfer Rates | 1200 to 19,200 baud (Default: 9600 baud, 8 data bits, no parity, 1 stop bit) |
| Bit Transfer Type | Differential signal |
| Line Impedance | 120 ohms |
| Maximum Cable Length | Approximately 1000 m (twisted pair) |
| Data Buffers | 128 bytes (receive), 16 bytes (transmit) |
| Power Supply | Via the K-bus |
| K-bus Current Consumption | Typical 65 mA |
| Power Contacts | None (no power contacts) |
| Electrical Isolation | 500 V (K-bus / signal voltage) |
| Process Image Bit Width | Input/output: 3 x 8-bit user data, 1 x 8-bit control/status (up to 5 x 8-bit user data possible) |
| Wiring Technology | Pluggable wiring (tension clamp connection) |
| Connection Cross-section | Solid conductor: 0.08 to 1.5 mm²; Flexible: 0.08 to 1.5 mm²; Ferrule: 0.14 to 1.5 mm² |
| Connection Cross-section AWG | AWG 28 to 16 (solid/stranded); AWG 26 to 16 (ferrule) |
| Stripping Length | 9 to 10 mm |
| Dimensions (W x H x D) | 12 mm x 100 mm x 68 mm |
| Weight | Approx. 60 g |
| Mounting | 35 mm DIN rail (EN 60715) with locking mechanism |
| Operating Temperature | 0 to +55 degC |
| Storage Temperature | -25 to +85 degC |
| Relative Humidity | 95 %, non-condensing |
| Protection Class | IP20 |
| Certifications | CE, UL, ATEX |
| Ex Marking | II 3 G Ex nA IIC T4 Gc |
The BECKHOFF KS6021 features a pluggable wiring design that simplifies replacement tasks. When replacing an existing terminal, the wired pluggable block can be removed from the terminal housing without disconnecting the individual signal wires. Ensure the system is powered down, disconnect the plug block, swap the terminal housing on the DIN rail, and securely snap the plug block back into the new unit to minimize downtime and prevent wiring errors.
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Returns & Warranty

The BECKHOFF KS6021 is a high-performance Bus Terminal with a pluggable wiring level, designed to enable direct connection of devices with RS422 or RS485 interfaces to the K-bus system. It provides an electrically isolated, interference-immune interface for bidirectional data transfer over long distances, making it highly suitable for integrating serial communication devices into standard Beckhoff I/O networks.
Operating in full or half-duplex mode, the BECKHOFF KS6021 transmits and receives differential signals using a dedicated TxD and RxD channel architecture. The serial interface operates independently of the underlying bus system, allowing the controller to transmit data collision-free and receive data with an integrated buffer system. This model features a pluggable wiring design (indicated by the KS prefix), which simplifies terminal installation, replacement, and wiring verification without disconnecting individual field conductors.
| Manufacturer | BECKHOFF |
| Model | KS6021 |
| Product Type | Bus Terminal with pluggable wiring level |
| Communication Interface | RS422/RS485 |
| Data Channels | TxD and RxD, full or half-duplex |
| Data Transfer Rates | 1200 to 19,200 baud (Default: 9600 baud, 8 data bits, no parity, 1 stop bit) |
| Bit Transfer Type | Differential signal |
| Line Impedance | 120 ohms |
| Maximum Cable Length | Approximately 1000 m (twisted pair) |
| Data Buffers | 128 bytes (receive), 16 bytes (transmit) |
| Power Supply | Via the K-bus |
| K-bus Current Consumption | Typical 65 mA |
| Power Contacts | None (no power contacts) |
| Electrical Isolation | 500 V (K-bus / signal voltage) |
| Process Image Bit Width | Input/output: 3 x 8-bit user data, 1 x 8-bit control/status (up to 5 x 8-bit user data possible) |
| Wiring Technology | Pluggable wiring (tension clamp connection) |
| Connection Cross-section | Solid conductor: 0.08 to 1.5 mm²; Flexible: 0.08 to 1.5 mm²; Ferrule: 0.14 to 1.5 mm² |
| Connection Cross-section AWG | AWG 28 to 16 (solid/stranded); AWG 26 to 16 (ferrule) |
| Stripping Length | 9 to 10 mm |
| Dimensions (W x H x D) | 12 mm x 100 mm x 68 mm |
| Weight | Approx. 60 g |
| Mounting | 35 mm DIN rail (EN 60715) with locking mechanism |
| Operating Temperature | 0 to +55 degC |
| Storage Temperature | -25 to +85 degC |
| Relative Humidity | 95 %, non-condensing |
| Protection Class | IP20 |
| Certifications | CE, UL, ATEX |
| Ex Marking | II 3 G Ex nA IIC T4 Gc |
The BECKHOFF KS6021 features a pluggable wiring design that simplifies replacement tasks. When replacing an existing terminal, the wired pluggable block can be removed from the terminal housing without disconnecting the individual signal wires. Ensure the system is powered down, disconnect the plug block, swap the terminal housing on the DIN rail, and securely snap the plug block back into the new unit to minimize downtime and prevent wiring errors.
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 |
Germany
|