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 ABB PM556-TP-ETH (Product ID: 1SAP121200R0071) is a high-performance central processing unit module from the AC500 programmable logic controller family. This controller features a built-in 512 kB user data memory with a 642 kB total memory capacity executed on integrated RAM, enabling processing speeds as fast as 0.00008 ms for industrial application code execution. Designed to fulfill decentralized or localized control demands, the hardware architecture delivers 8 embedded digital inputs and 6 transistor digital outputs. Communication options include one dedicated Industrial Ethernet port, one RS485 serial connection interface, and two option slots for flexible peripheral hardware and protocol scalability. Operating on a rated nominal input voltage of 24 VDC, this compact module provides efficient sequencing, machine tool interfacing, and reliable process logic execution across distributed automation frameworks.
| Parameter | Value / Specification |
|---|---|
| Manufacturer | ABB |
| Product Main Type | PM556 |
| Product Name | Distributed Automation PLCs |
| Memory Size | 642 kB |
| Memory Type User Data | RAM |
| Controller Processing Time | 0.00008 ms |
| Number of Digital Inputs | 8 |
| Number of Digital Outputs | 6 (Transistor Type) |
| Number of Configurable I/Os | 0 |
| Industrial Ethernet Interfaces | 1 |
| RS-485 Interfaces | 1 |
| Option Slots | 2 |
| Input Voltage Type | DC |
| Rated Voltage (Ur) | 24 V DC |
| Supply Voltage | 20.4... 28.8 V DC |
| Product Net Width | 82 mm |
| Product Net Height | 135 mm |
| Product Net Depth / Length | 74 mm |
| Product Net Weight | 0.28 kg |
| Gross Weight | 0.446 kg |
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Returns & Warranty



The ABB PM556-TP-ETH (Product ID: 1SAP121200R0071) is a high-performance central processing unit module from the AC500 programmable logic controller family. This controller features a built-in 512 kB user data memory with a 642 kB total memory capacity executed on integrated RAM, enabling processing speeds as fast as 0.00008 ms for industrial application code execution. Designed to fulfill decentralized or localized control demands, the hardware architecture delivers 8 embedded digital inputs and 6 transistor digital outputs. Communication options include one dedicated Industrial Ethernet port, one RS485 serial connection interface, and two option slots for flexible peripheral hardware and protocol scalability. Operating on a rated nominal input voltage of 24 VDC, this compact module provides efficient sequencing, machine tool interfacing, and reliable process logic execution across distributed automation frameworks.
| Parameter | Value / Specification |
|---|---|
| Manufacturer | ABB |
| Product Main Type | PM556 |
| Product Name | Distributed Automation PLCs |
| Memory Size | 642 kB |
| Memory Type User Data | RAM |
| Controller Processing Time | 0.00008 ms |
| Number of Digital Inputs | 8 |
| Number of Digital Outputs | 6 (Transistor Type) |
| Number of Configurable I/Os | 0 |
| Industrial Ethernet Interfaces | 1 |
| RS-485 Interfaces | 1 |
| Option Slots | 2 |
| Input Voltage Type | DC |
| Rated Voltage (Ur) | 24 V DC |
| Supply Voltage | 20.4... 28.8 V DC |
| Product Net Width | 82 mm |
| Product Net Height | 135 mm |
| Product Net Depth / Length | 74 mm |
| Product Net Weight | 0.28 kg |
| Gross Weight | 0.446 kg |
Global Express Shipping
Returns & Warranty
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| Color pattern |
Black
|
| Country of origin |
Switzerland
|
| Power source |
DC Power
|